Posted on

4R100 Transmission Spotlight

4R100 Transmission Spotlight

The Ford E4OD and 4R100 four-speed automatic transmissions were basically the same exact transmission, just with different names. The Ford E4OD transmission was updated in 1998 to the newer 4R100. Both the E4OD and 4R100 were electronically controlled transmissions, replacing the C6’s hydraulic-controlled system. To follow Ford’s new naming schemes for its other transmissions, Ford eventually renamed the E4OD as the 4R100 and the release of Ford’s Super Duty in 1999 kick-started an explosion of aftermarket performance parts for the revamped 7.3L Power Stroke. The 4R100 automatic transmission was mostly similar to the earlier E40D, but with some key changes to internal components in order to increase its durability when installing behind the popular Power Stroke Diesel Engine. In 1999, the 4R100 was fitted with a PTO for auxiliary equipment attached to heavy-duty trucks.

The 4R100 also matched Ford’s big 7.3-liter Power Stroke diesel engines from 1999 through 2003. The 4R100 reflected Ford’s new identification system for its transmission lineup, but it also solved some problems associated with the older E4OD. While the E4OD transmission problems were not decidedly major or even widespread, Ford developed the newer 4R100 with specific plans to resolve these issues. Even the 4R100 had its own problems, failing to maintain the increased torque output of the bigger engines available at the time. Aftermarket 4R100 modifications seemed to solve the issue by raising its torque capacity to over 1,000 foot-pounds. Among the aftermarket modifications were a high-performance shift-kit and power valve, along with a heavy-duty clutch. In 2004, when the 6-liter Power Stroke engine eventually replaced the 7.3-liter version, the Ford 4R100 transmission disappeared with it.

Ford reserved the 4R100 transmission for performance trucks and heavy-duty sport utility vehicles. The E4OD and 4R100 were huge transmissions at 27.25 inches long and not easily applicable to non-Ford trucks and vans. Shoehorning the transmission into another vehicle requires extensive modifications. They decided to match the transmission with engines in:

  • the 1999 to 2004 Ford SVT Lightning high-performance truck,
  • the 2002 to 2003 Ford F-150 Harley Davidson Special Edition,
  • the 1999 to 2003 Ford F-250 and larger Super Duty trucks,
  • the 1999 to 2003 Ford Expedition SUV equipped with the 5.4-liter V-8,
  • the 2000 to 2003 Ford Excursion, and
  • the 1999 to 2004 Ford E-Series vans.

The gear ratios for the E4OD and 4R100 transmissions were identical, with the 4R100 having a step 2.71 first gear that’s great for trucks towing a heavy load. The overdrive gear ratio is 0.71, which can help improve the fuel efficiency of this large diesel motor. The second gear ratio is 1.54, with the third gear ratio being a straight 1:1 ratio.

The 4R100 is a computer controlled transmission, which gives the truck owner the option of using a handheld controller to modify the characteristics of the transmission. The firmness of the shifts, line pressure, and RPM at which the transmission shifts is all adjustable with a handheld tuner. The transmission can even be reprogrammed to compensate for larger diameter tires.

Posted on

200-4R Transmission Spotlight

200-4R Transmission

For the 1981 model year of General Motors vehicles, the 200-4R transmission was introduced in 1980. The 200-4R is the lesser known of the two overdrive transmissions made by General Motors in the 1980’s, but they are still considered part of the Turbo-Hydramatic series that began in the 1930’s.The components were prone to failure in the earlier TH200 model and were improved in the later 1980’s with this line of transmissions. The 200-4R transmission was used with high-power applications, especially the Buick Grand National and the 1989 Pontiac Firebird Trans Am Indy 500 Pace cars. The TH200-4R was configured with several different torque converters and gear ratios, depending on the vehicle application. Many of the vehicles out there that still exceed 700 horsepower are still using the TH200-4R transmission to this day.

Unlike the 700R4, most 200-4Rs have a multi-case bell housing for use with Chevrolet, Buick, Oldsmobile, Pontiac, and Cadillac engines, but the 200-4R shares mounting placement with the TH-400 transmission. Since the outside dimensions are close to the TH-350 transmission, 200-4Rs are often swapped in place of TH-350’s in older vehicles to provide an overdrive gear.

The external dimensions are similar to the Turbo 350 so it is often swapped in older vehicles to provide an overdrive gear. In addition, it has a multicase bell housing for use with Chevrolet, Buick, Oldsmobile, Pontiac, and Cadillac power plants, although the TH200-4R was phased out after 1990. Early models had PRND321 on the cluster, while later models had PRN(D)D21, with the left D identified as the overdrive gear by a square or oval ring.

The TH200-4R transmission, like the TH-350, uses a 27-spline output shaft, which is similar in length to the TH-350 and the TH-200 models, making it a top selection for many overdrive conversions. The TH200-4R transmission is also similar in length to the Powerglide and the Pontiac Super-Turbine 300, which makes it a popular model for converting from a two-speed to a four-speed automatic.

The TH200-4R transmission has a 2.74:1 first gear ratio, with overdrive being 0.67:1. It has an oddly-shaped 16-bolt pan with 13mm bolt heads. The TH200-4R was primarily used in GM rear wheel drive cars that were equipped with the 231 Buick, 301 Pontiac, and the Oldsmobile 307, 350 gas and diesel engines between 1981 and 1990. Many Chevrolet 267 and 305 V-8 engines also came with the TH200-4R transmission because of the multi-fit bell housing. You can still find a TH200-4R transmission in any of these cars:

  • 1981-’90 Cadillac Fleetwood, Deville and Brougham
  • 1981-’88 Buick LeSabre, Electra RWD, Chevelle, Monte Carlo, Malibu & El Camino
  • 1982-’90 Chevrolet Impala, Caprice, Olds Delta 88, 98 & Custom Cruiser
  • 1984-’87 GMC Caballero & Pontiac Grand Prix
  • 1983-’88 Olds Cutlass 442 & Supreme
  • 1983-’89 Pontiac Bonneville, Parisienne & Safari Wagon
  • 1981-’87 Buick Regal
  • 1981 Buick Century & Pontiac Firebird 301

The best TH200-4R transmissions to mount in your vehicle, if you’re looking for performance-grade parts, are typically the units manufactured for the Buick Grand National, Oldsmobile 4-4-2 and Chevrolet Monte Carlo SS during 1986-’87 because this model used a special valve body, a larger reverse boost valve, second to third intermediate servo, and a specially manufactured governor assembly.

Posted on

C6 Transmission Spotlight


The Ford C6 is a heavy-duty automatic transmission built by Ford Motor Company between 1966 and 1996. It was marketed as the “SelectShift Cruise-O-Matic.” Compared to its predecessor MX transmission, the C6 offered lower weight, less complexity, less parasitic power loss, and greater torque capacity for larger engines. It did this without exceeding the packaging dimensions of the MX. These design goals were in line with those of the C4 for smaller engines.

To cut down on weight and cost, the C6 featured a simple, three speed Simpson planetary gearset as well as over 10 lb (4.5 kg) of powdered metal. To increase shift quality and long-term durability, it became the first automatic transmission designed to use the Borg-Warner flexible shift band. The C6 also included disc clutch plates instead of bands on the low and reverse gears, including new composite plates and valves. This gave it the capability to handle upwards of 475 ft-lb of torque.

Prior to 1966, Ford FE and MEL big-blocks were fitted with cast-iron MX and FX 3-speed automatic transmissions. In 1966, Ford introduced its own heavy-duty C6 3-speed automatic transmission for high-torque applications behind large-displacement big-block V-8s. Although the C6 has a completely different case and external components than the C4, it is virtually the same internally to the C4—on a larger scale for heavy-duty use.

The C6 was produced with four basic bell housing bolt patterns over its long production life and is a very rugged transmission designed for high-power applications. The round six-bolt pattern is for FE-series big-block, which includes the 332, 352, 361, 360, 390, 406, 427, and 428 engines. There is another distinctive six-bolt bell housing pattern for the 429/460-ci 385-series big-blocks and the 351M and 400M Cleveland-based, raised-deck V-8s. The six-bolt pattern arrived to the C6 in 1968 with the 429/460 big-block V-8s. There’s also the small-block C6 originally intended for 351W and 351C engines, which fits any six-bolt 289/302/351W/351C small-block bell housing bolt pattern.

By the 1970s, Ford had a respectable lineup of modern lightweight automatic transmissions. An ironic footnote to this story is the weighty cast-iron FMX transmission, which remained in production until 1981 behind 351W small-block engines. It was an easy off-the-shelf solution for Ford, which needed the FMX to keep up with production demands when there weren’t enough C4 and C6 transmissions to go around.

Later, there was a C6 transmission produced for Diesel engines beginning in the 1980s, before the E4OD (4R100) was introduced in 1989. The long history of production really highlights this transmission’s reputation for durability. Despite the E4OD’s presence, Ford still continued to build the C6 up until 1996 for many commercial and industrial applications.

The C6 transmission is still very popular in the sport of drag racing today, with units equipped with manual valve bodies and transmission brakes. It is also widely used in off-road applications due to its reputation of being nearly indestructible. They are available in small block, big block or round bell housing depending on the motor you want to equip it with. We can custom build these to meet or exceed your expectations, check out our store to find out more.

Posted on

4L80E Transmission Spotlight

4L80E Transmission

The 4L80E was a series of automatic transmissions from General Motors designed for longitudinal engine configurations. It was a new model based on the design of the Turbo-Hydramatic 400, first produced in the year 1963. 4L80Es were initially only available in Chevrolet or GMC trucks, vans, and commercial vehicles, as well as the Hummer H1. It was also adopted by Rolls Royce in 1991 and modified initially for use in the Bentley Continental R, and later other Rolls Royce, Bentley, and Aston Martin luxury vehicles.

The 4L80 nomenclature denotes that the transmission is a 4-Speed, Longitudinally-mounted, and for 8000 lbs. vehicle weights. Maximum engine input torque for the 4L80 is 440 ft. lbs. and the maximum output torque is 885 ft. lbs. The case is die-cast aluminum and was designed for vehicles up to 16,500 lbs. It’s RPO code is “MT1″ and has been domestically manufactured in GM’s Ypsilanti and Willow Run plants.

The torque converter is a fluid turbine drive and like those on its predecessor transmissions; the TH350C, 700R4, and 4L60, the 4L80E features a lock-up pressure plate for direct mechanically coupled driving from the engine crank. The 4L80E also features a 310 mm torque converter. As to length, this transmission is 26-1/4” long. This transmission typically accepts a 6.3-quart fill and features a dry weight of 254 lbs. that can weight up to ~268 lbs. when full. Like some earlier automatic transmissions, the 4L80E features one line pressure tap available for testing and diagnostic purposes, and also feature transmission cooling ports for external transmission oil coolers.

The 4L80E is intended to operate between the duty range of the 4L60E and the Allison series transmissions, and prior to the current high-powered light-duty (2500-3500 series) truck diesel revolution, Allison transmissions were essentially only used in the medium-duty class (4000 series) trucks. This made the 4L80E the go-to transmission of the era, amongst the popular Big Block style gas and diesel engines of the 1990’s.

In 2006, with the introduction of the landmark and innovative upstart, the 4L80 began to be replaced in several applications, which was without a doubt GM engineers’ ultimate intention. Yet, the 4L80 continued to be used in the GM’s truck line-up such as in 2007 when it was introduced into the Suburban and Yukon XL vehicles with the 6.0L engine.

The 4L80’s staying power found it installed in several vehicles through 2009, such as the G-series vans, the AM General Hummvee, the W-Series, Isuzu and Workhorse chassis trucks. GM 4L80E transmissions are often overlooked, yet is a top-rated leading option. This four-speed overdrive trans works with just about any power level and engine combination. It is based largely on the TH400 in strength and parts. The difference is the added overdrive gear, advanced electronic controls, and a lock-up torque converter.

Posted on

TH400 Transmission Spotlight

th400 th-400 turbo 400

Turbo-Hydramatic or Turbo Hydra-Matic is the registered trade name for a family of automatic transmissions developed and produced by General Motors. These transmissions mate a three-element turbine torque converter to a Simpson planetary gear train, providing three forward speeds plus reverse. The TH400 is highly regarded for its supreme durability. This model has a conservative rate of 450 ft. lbs of input torque, though that can be easily upgraded with aftermarket improvements. These transmissions can come up to a maximum of 1000 torque. The TH400 transmission has available a variety of performance ratings, such as mild, heavy duty, super sport, and SS Xtreme. The higher model that is chosen, the higher rated the horsepower and torque will be.

In its original incarnation as the Turbo-Hydramatic 400, it was first used in the 1964 model year in Cadillacs. The Buick version, which followed shortly thereafter, was known as the Super-Turbine 400. By 1973, THM units had replaced all of GM’s other automatic transmissions including Chevrolet’s Powerglide, Buick Super Turbine 300, and Oldsmobile Jetaway. Starting in the early 1980s, the Turbo-Hydramatic was gradually supplanted by four-speed automatics, some of which continue to use the “Hydramatic” trade name. It is an immensely popular transmission in the automotive industry as well as the aftermarket. Today they are found in GM’s, Jeeps, Jaguars, Rolls-Royces, Ferraris and others.

The THM400 was the first three-speed, Simpson-geared automatic to use overrunning clutches for both first and second gear reaction, a feature that eliminated the need to coordinate the simultaneous release of a band and application of a clutch to make the 2-3 gear change. Owing to this feature, as well as the use of a large, multi-plate clutch to provide second gear reaction, the THM400 is able to withstand very high input torque and an enormous number of shifting cycles, as would be encountered in frequent stop-and-go driving. As a result, it has met with considerable success in commercial vehicle applications.

Gear Ratios of the TH400 are:

  • First Gear – 2.48:1
  • Second Gear – 1.48:1
  • Third Gear – 1.00:1
  • Reverse – 2.07:1

The 400 transmission has a main case of cast aluminum alloy with a length of 24-3/8″ long. Its aluminum case is essentially smooth. The rear mounting face of the transmission has a hex bolt pattern with ribs running forward longitudinally. The fluid pan shape is irregular (see image, left), being likened unto a distorted Texas pattern. The TH400 is the largest of the common GM auto transmissions, but still surprisingly compact in light of the immense power they can handle.

There are two significant variations of the TH400. The TH375 was a version of the transmission used from 1972-1976 in smaller displacement cars. It is identified easiest by its “375-THM” designation cast in the underside of the tail housing. The TH475 was an extra-heavy-duty version, and was found in larger trucks from 1971 on.

By 1980, the relatively heavy THM400 was being phased out of usage in passenger cars in response to demand for improved fuel economy. The THM400 was utilized in the C- and K-series (full-size) Chevrolet/GMC pickups and G-series (full-size) vans until 1990 when GM switched over to the 4L80E. Today, the United States Army HMMWV is the only vehicle using the THM400. The civilian Hummer H1 originally had the 3L80s, but the current model has had a 4L80E since the mid-1990s.

Posted on

E4OD Transmission Spotlight


The E4OD transmission system was introduced in 1989 and used in both light and heavy duty applications. The E4OD was the successor to the C6 transmission and was Ford’s first electronically controlled automatic transmission. It comes equipped with four forward speeds as well as electronic shift controls to replace the hydraulic governor control of its predecessor. The E4OD transmission can be found in applications such as the Bronco, the Expedition, and the F-Series:

  • 1990–1996 Ford Bronco
  • 1989–1998 Ford E-Series
  • 1997–1998 Ford Expedition
  • 1989–1998 Ford F-Series
  • 1993–1995 SVT Lightning

Ford’s E4OD automatic transmission was designed from many improvements, changes, and upgrades to the earlier C6 system. Improvements include a higher contact ratio in planetary gear sets, an improved hydraulic pump, and upgraded coast clutch. The E4OD also featured the addition of an overdrive gear set, which greatly improved fuel efficiency over the C6’s direct drive top gear. The E4OD also introduced the concept of electronic shift controls, replacing hydraulic pressure regulation and shift functions with electric shift solenoids. In this transmission, shifts would be commanded electronically by means of the EEC-IV on-board control processor.

Ford called the transmission control processor the ‘Electronic Control Assembly’, or ECA. The unit could also be interpreted as a modern transmission control module, or TCM. The ECA controls transmission shift timing, regulates transmission line pressure, controls the torque converter lockup sequence, and provides certain diagnostics of the transmission. In gasoline applications, the ECA controls electronic functions for both the engine and transmission. In diesel applications, the ECA instead acts as a stand-alone controller for the transmission and does not play a major role in engine function.

The E4OD was eventually replaced by the 4R100, which was Ford’s transition to an alternative name for their drivetrain products, since the transmission is similar to, but not interchangeable with the E4OD. The 4R100 included changes, upgrades, and improvements necessary for Ford’s automatic transmission platform to compete with the F-Series diesel program.

A flashing “OD” light on the shift lever of an E4OD indicates that the ECA has detected a transmission problem and is alerting you to take the vehicle in for diagnostics, service, and/or repair. The E4OD was improved multiple times over the course of its existence – when overhauling the E4OD, so you should consult with your transmission expert to ensure you receive any and all updated components that may provide favorable reliability and durability.

Posted on

6R80 Transmission Spotlight


The 6R80 is a six speed automatic transmission made by Ford. It is designed for rear wheel drive vehicles. It was first put into production in 2007 and is still being made today.  It is used in many popular Ford vehicles, including the Expedition, Lincoln Navigator, Explorer, Explorer Sport, Mercury Mountaineer, F150, Ford Territory, Mustang and Ranger. The 6R80 transmission will bolt directly to all Modular and Coyote Ford engines and can be adapted to virtually any vehicle combination relatively easily. With a variety of parts available to simplify the transmission swap, it is an excellent choice for a performance upgrade or when swapping from a manual to automatic transmission.

The 6R80 was first introduced in 2009 and is manufactured under ZF license at the Ford Transmission Plant in Livonia, Michigan. It can be found behind a multitude of Ford engines ranging from the 3.7 V6, all the way up to the robust 6.2L V8. While the transmission is offered in several engine applications, each transmission variation is integrated differently depending on engine and vehicle application. Enhancements were added by Ford to further improve the transmission, including the addition of a ratchet-style low one-way clutch, and removal of the internal TCU for the 2011 model year, easily enabling stand-alone control.

This six-speed transmission features an elegant, robust, band-free design that is simpler than most four speed automatic transmissions. It uses five clutch packs and a single one-way clutch to achieve six forward ratios, whereas most four speed units utilize six or more clutches and/or bands, with at least one one-way clutch to achieve four gears. This allows better reliability, better shift quality, and reduced rotating mass.

Although the 6R80 has 6 forward gears, the transmission is only slightly larger than earlier four-speed automatics. The transmission is without question stronger than earlier Ford 4 speed transmissions. The 6R80 can likely handle up to 1000HP with proper ECU tuning and potentially even more with the implementation of aftermarket components. Stock applications already employ a multi-plate torque converter clutch, enabling greater power handling in lockup. Despite having 6 forward gears, the transmission is only slightly larger and heavier than light-duty four-speed automatics, such as the 4L60E and 4R70W.

One primary advantage of using a six-speed clutch-to-clutch transmission, like the 6R80, is the tighter gear ratios when compared to traditional four speed automatics. From first to sixth gear, there is a 604:1 ratio spread. This efficiency will not only improve the acceleration and performance of high-horsepower applications, but also make a dramatic improvement when applied to near-stock or mildly-modified vehicles. With six gears, it can better utilize each ratio to get the most efficiency and performance out of your vehicle’s combination.

The gear ratios offer a generous ratio spread of 6.04:1 from first to sixth gear, and the ratios are very close together, rivaling most four-speed transmissions. From second to sixth gear, the ratios are extremely close, providing world-class performance. The 6R80 also uses synthetic transmission fluid (Mercon LV). The transmission used in the Ford F-150, has a fluid capacity of 12.10 quarts and weighs roughly 215 lbs. The 6R80 measures 23.75” and utilizes a large 31 spline 4wd output shaft. In 2011 Ford removed the internal TCU enabling the usability of stand-alone computers.

Sooner or later you will be faced with a decision to replace the 6R80 transmission in their vehicle, be it from excessive mileage or from overheating the transmission. We highly recommend that you consider buying a remanufactured transmission over one that was simply rebuilt. Ideally, you should keep the transmission below a maximum temperature of 200 degrees. For every 20 degrees you go over 200 degrees, you cut the potential lifespan of the transmission by a factor of two.

This transmission has been largely avoided or ignored in the past due to a stand alone control system not being available. There is already a growing ecosystem of swap parts available for the 6R80, including bell housing adapters for various non-modular Ford V8s, with others likely to follow. The best way to combat excessive heat is to install an aftermarket transmission cooler on your customer’s vehicle before it ever overheats, so for a little added protection, consider installing a transmission cooler with a built in fan.

Posted on

48RE Transmission Spotlight


The 48RE four-speed automatic transmission represents an evolution of the previous 47RE transmission model and can be found combined with the Cummins Turbodiesel in Ram pickups from 2003 to 2007 model years. The 48RE transmission design is both heavier and stronger than the 47RE, although the two transmissions share identical ratios. Although the 48RE is considered a significant improvement over its predecessor, it quickly became outdated as power ratings for the Cummins Turbodiesel surged to over 600lb-ft by 2007, the last model year of the 5.9L Cummins ISB. Chrysler would ultimately replace the 48RE transmission with its first diesel specific transmission platform, the 68RFE, following the development of the 6.7L Cummins.

The 48RE transmission features four shift schedules, technically known as governor pressure curves. Governor pressure is electronically controlled relative to engine speed and is used to command upshifts and downshifts according to engine speed and load. The four schedules are as follows:

  • When transmission fluid temperature is at or below 30° F – Shifts are delayed and the engine is allowed to rev higher to help the engine and transmission reach normal operating temperature in less time. Shifts are typically harsh while this schedule is in effect.
  • When transmission fluid temperature is at or above 50° F – The transmission’s normal adaptive shift strategy is in effect. The adaptive strategy is a dynamic shift schedule that commands upshifts and downshifts based on various operating conditions, including engine speed and load.
  • With “wide open throttle” – At full throttle, upshifts are originally commanded by the PCM at predetermined optimal engine speeds. The PCM perpetually learns and creates an optimal upshift schedule based on the time required to complete a shift at a given engine speed/load compared to the desired preprogrammed values. The wide open throttle shift schedule is therefore adjusted routinely based on the outcome of transmission shift events.
  • When transfer case 4WD low engaged – In order to compensate for inherent accelerator pedal sensitivity in low range (resulting from significantly higher engine torque multiplication through the drivetrain), the PCM will command upshifts much sooner when the transfer case is placed in the lower range.

The transmission also features a “Tow/Haul” setting that can be activated by a shifter-mounted switch. The 48RE’s Tow/Haul function is not necessarily a “smart” function like those found on modern engine/transmission combinations that have integrated exhaust brake technology and vehicle speed management systems. When the Tow/Haul setting on the 48RE is activated, torque converter lockup is engaged and the transmission shift schedule eliminates overdrive (4th gear) upshifts, therefore direct drive (3rd gear) becomes the final available drive gear. Towing significant weight in overdrive is not recommended, as drive wheel torque is reduced and the load placed on the transmission can contribute to a reduced product lifespan.

The 48RE automatic transmission features an actual input torque rating between 560 and 570 lb-ft of torque; whereas, the standard Cummins Turbodiesel peaked at 610 lb-ft by 2005. As a result, the 5.9L Cummins was designed to detune itself when necessary to promote the longevity of the transmission. The engine will produce its peak 610 lb-ft torque, but only in cases where accessory load brings the actual engine torque output into the 570 lb-ft torque range. In all other cases, the engine will detune to roughly 570 lb-ft of torque under full load. The limits of the transmission are quickly realized in the presence of performance enhancing modifications such as electronic tuning devices.

The 48RE transmission is the weakest point on a Dodge Cummins truck. Not only do they fail on trucks with minor upgrades, but even stock vehicles have been known to be too powerful for the transmission to endure its natural lifespan. A heavy duty truck needs parts which can stand up to heavy trailers, stop-and-go commutes to work, or high-horsepower applications. That’s why we might recommend modifying the transmission to make it the strongest and most reliable part of your drivetrain.

Modern diesel performance is still advancing at a radical pace. Current pickup truck engines can make nearly 1,800lb-ft of torque at the wheels yet still be driveable on the street. Getting that much power to the ground; however, is another matter altogether, and virtually every single part in a transmission could be its weak weak link. Make sure you have the right components in your truck, whether you currently have a 48RE automatic transmission or are looking to replace your current system with one of ours.

Posted on

5R110W Transmission Spotlight


The Ford 5R110W transmission is a heavy-duty five-speed automatic transmission. It is primarily used in the Ford F-Series Heavy Duty pickup trucks and their Heavy Duty Chassis program. The 5R110W is loosely described as a redesign of Ford’s earlier 4R100 automatic transmission. The 5R110W “TorqShift” transmission was introduced alongside the 6.0L Power Stroke diesel for the 2003 model year as a diesel specific transmission which is closely integrated into the function of the engine. This transmission is good for towing, snow plowing, 4WD, or for any other similar high-performance needs. Many of these can be found in delivery trucks, food trucks, school buses, and motorhomes.

The transmission is advertised as a five-speed, although in actuality it features six forward speeds. Under normal operating conditions, the transmission shifts 1st-2nd-3rd-5th-6th. A secondary shift sequence is commanded when the ambient temperature drops below 5° F and shifts 1st-2nd-3rd-4th-6th. The transmissions marginally shorter 4th gear is used in cold weather to force higher engine speeds and therefore help the engine/transmission reach the normal operating temperature in less time.

Since they are often used in vehicles that are used and abused in harsh environments, the 5R110W transmission is often given a rough ride, with the number one killer of the 5R110W being excessive heat resulting from abuse. Towing over the factory payload limit and keeping your foot on the gas going up steep hills with a heavy load are two of the most common examples of this type of abuse. So here’s the bottom line: if you have a programmer, power adders or tow heavy loads, then you must have a High Performance or Heavy Duty transmission and torque converter so that your transmission will last.

The 5R110W is unique in that it lacks a typical valve body – instead, the 5R110W contains a “solenoid body”, which contains a series of 7 electronic shift solenoids. Problems with the 5R110W can be vaguely separated into two main categories. Mechanical problems may include a physically stuck solenoid, worn clutches, damaged gear set, while electrical problems may include a solenoid that is not functioning correctly, faulty or missing input from one of the various sensors, etc. Engine problems may be inappropriately diagnosed as a transmission issue and therefore should be repaired before attempting to troubleshoot a transmission.

Posted on

68RFE Transmission Spotlight

68RFE Transmission

Chrysler’s 45RFE transmission, launched in 1998, used three planetary gear sets instead of the normal two being used at the time. The transmission later evolved into Chrysler’s first diesel specific transmission, the 68RFE, which was introduced alongside the 6.7L Cummins turbodiesel during the 2007 model year with the Ram and Pickup Lines. The newer transmission design provided the benefits of modified internal components to handle the increased torque and revised gear ratios for larger applications. Monster provides a wide variety of different builds for this transmission for additional ratings of horsepower and torque. These include the Heavy Duty, Super Duty, and Super Duty Xtreme models of Dodge Ram trucks.

The transmission’s band-less design and upgraded filtration system have proved to be significant improvements over previous transmissions, allowing for extended time between service intervals, while also reducing service costs. Under partial throttle, shifting into gears above third was delayed; and the system was likely to kick down under part throttle into fourth and fifth. A new Tow or “Haul” mode allowed for faster and crisper shifting in order to reduce engine wear, while still allowing overdrive unless the driver has previously locked it out. The 68RFE transmission was the biggest leap forward in terms of Dodge automatic transmissions since the inception of the Dodge Cummins power plant.

In the past, four-speed transmissions were the weak link for the vehicle’s powertrain. And while the 68RFE has proven itself in many respects, it has also shown plenty of weaknesses, as well. As power is increased above stock, heavy loads are hauled, and miles are racked up, the 68RFE’s are failing, partly due to the electronically controlled nature of these transmissions.  The 66RFE was introduced in 2012 as a lighter-duty version of the 68RFE, with the main differences between the transmissions being in the torque converter.

The 68RFE kept the basic clutch and hydraulic control design, matched with heavier-duty planetary gears, toothed differently to increase their capacity. The shafts, clutches, pump, torque converter, and other parts were also redesigned to handle the Cummins 6.7 liter diesel. The 263-pound 68RFE has roughly the same torque capacity as the Aisin automatic option in Ram heavy-duty pickups, but the Aisin allows for a power takeoff (or PTO), while the 68RFE does not; the Aisin also had a steeper first gear for better off the line power, with the same sixth gear ratio.

The processes involved to build more robust replacement parts has been tedious for the aftermarket manufacturers.  However, with several years, and many miles under their belts, most of the manufacturers have determined the best methods to manufacture “bulletproof” replacement parts, leaving a wide selection of proven parts now available.

Posted on

Allison 1000 Transmission Spotlight

Allison 1000

The Allison 1000 is a 6-speed double overdrive transmission produced by the Allison Transmission Company in Indianapolis, IN, and Baltimore, MD. Allison transmissions have a global reputation for being extremely durable, which is why they’re cheaper to operate than other equally equipped vehicles. The low minimum maintenance requirements result in cheaper overall maintenance costs.

This heavy duty transmission can be found in all sorts of motorhomes and custom applications, along with the Chevrolet Silverado, the Hummer H1, the Chevrolet B-Series and the GMC Sierra. It can also be found in the Chevrolet Kodiak and the GMC Topkick. Starting in 2001, Chevy 2500 HD and 3500 trucks have had the option of being equipped with the Allison transmission. The Duramax-powered engine in the Silverado 2500 and 3500 trucks are now combined with the Allison 1000.

The Allison 1000 is an extremely heavy duty transmission, capable of handling up to 620 lb-ft of torque. Compare this to GM’s highest-rated transmission, the 4L80E which can only handle 420 lb-ft of torque. Put into use in 2006, the Allison 1000 transmission is still in production.

Early Allison 1000’s were initially 5-speed transmissions, but in 2006 they added a sixth overdrive gear. The creators of the Allison transmission realized that the diesel engines offered in diesel pickups were constantly increasing in horsepower and torque. The creators of the Allison transmission realized that the diesel engines offered in diesel pickups were constantly increasing in horsepower and torque. They knew that a strong transmission would be needed to handle GMC’s Duramax engine.

The adaptive learning technology provides a comfortable driving experience and helps you avoid any rough shifting experiences. The Allison 1000 is completely electronically controlled to adapt to your current driving style. The computer in the Allison 1000 constantly adjusts shift clutch pressure to match engine torque and vehicle load. The computer also has pre-programmed tables for reference. It attempts to make the shifts match the programmed table to maximize durability and drivability.

Most commonly, the transmission may go into “Limp Mode” during the 4 to 5 upshift or between 5 to 4 downshift while under hard acceleration. This will cause a check engine light to come up on your dash and the truck to be limited by power and speed. When this happens, the most common reported code is P0700. GM defines P0700 as “Transmission Control Module Requested MIL Illumination”. Simply put, it’s a general code for transmission issues and generally is accompanied by another code such as P0701, P0702 or others.  

Many truck owners’ first reaction is to replace the Transmission Control Module (TCM) as soon as this code pops up. The reality is that further diagnosis is needed to tell what the issue is for sure, and the best way to resolve it. Never jump to conclusions with your transmission, and always take into consideration the circumstances behind the issue prior to the code coming up if you experience any problems.

Posted on

4L60E Transmission Spotlight

4L70E Level 3

The 4L60E is a four-speed automatic transmission produced by General Motors. It has been considered to be the best rendition of the finest overdrive automatic transmission ever produced. General Motors first induced the 4L60E transmission in 1993 as a replacement/upgrade to the 4L60, which itself was an upgrade from the 700R4. The 4L60E is a very capable 4-speed transmission with a 3.059 first gear ratio and a 0.696 final gear ratio, making it ideal for off the line performance while still providing decent mileage in overdrive.

The Corvette is General Motors flagship car. The 5th generation Corvette was a huge leap for GM. It incorporated so many new state of the art components over its predecessor that there are too many to count. The 4L60E differs from the 700R4 by being fully electronically shifted, and it has many internal upgrades that make it both stronger and more durable. The 4L60E could be found in many General Motors vehicles, including the Chevy Camaro, the Pontiac Trans Am, the Chevy Silverado, the Cadillac Escalade and the Buick Roadmaster. It is probably best known for its use in the 1994 -2004 5th generation Corvette.

While it’s common for car owners to perform many engine modifications, few give much thought to doing anything with the automatic transmission. Did you know you can pick up a full second, or more time reduction in the quarter mile by modifying your 4L60E transmission in your Corvette? Yes, it’s true and it’s not difficult to do. Let’s take a look at a few modifications you can make to the transmission in your GM or Chevy vehicle!

Shift Kits – There are a number of different shift kits available from a variety of different companies. Most of them come with the option to set them up for towing, street or street/strip use. Street/strip mode will usually result in the chirping of the tire under full throttle in first gear, given the ideal rear end gear ratio and adequate power levels. Shift kits can be broken down into two categories: modified valve bodies and electronic shift kits. Modify valve bodies use special plates with different size holes and check ball, stiffer springs and plugs to change the shifter characteristics.

Torque Converters – The stock converter used in the 4L60E is of the lockup type. Because of this, it is recommended that a stall converter of no more than 2600 rpm’s be used. A non-lockup converter is also available for those that want a higher stall speed. A popular option on the higher horsepower applications is the use of a converter with the anti-balloon plate option.

Transmission Coolers – There are literally hundreds of different types of transmission coolers available. It is always recommended to use the largest cooler possible. Coolers are available in the standard tube-type configuration and a more rugged stacked-plate design. Coolers are also available with built-in fans and temperature switches.

Transmission Pans – Most aftermarket pans are designed to increase the fluid capacity of the transmission. They are available in steel, chrome plated steel, and aluminum. Some have cooling fins or cooling tubes built into them. Most of them include a drain plug. Aluminum pans are generally sturdier and dissipate heat better than steel pans.

Wire Harnesses –  If the car originally came with the 4L60E than use of the stock wire harness is fine. For retrofit applications, special customer wire harnesses are available to work with either the factory computer or an aftermarket controller.

Fluids –  You can use the organic oil called for in the GM manual or you can use a synthetic fluid that meets the minimum requirements. Be sure to check the requirements for your individual year transmission and don’t forget to change the fluid on a regular basis. There are many options to upgrade the 4L60E to meet your requirements and desires.

Posted on

700R4 Transmission Spotlight

700R4 level 2 transmission

General Motors/HydraMatic introduced the 700R4 4-speed automatic transmission in 1982 (as a replacement to the TH350 3-speed automatic transmission) and used it in many of their popular vehicles with models beginning in the years through today. The 700R4 was one of the first overdrive transmissions used in General Motors vehicles from the Blazer to pickup trucks, and even the Corvette platform. The transmission is sometimes also referred by as the 4L60 (1990) or 4L60E (1993) for improved electronically-controlled models introduced later on. The 700R4 overdrive transmission platform is considered one of the best ever made.

The 700R4 automatic transmission is constructed of a single piece of cast aluminum. The part is 23.4 inches long, weighs 155 pounds, and holds approximately 11 quarts of transmission fluid. It is distinguished from the TH350 and TH400 in that it has a square oil pan, lacking the distinctive cut-off corner of the TH350 and the “Texas” shaped oil pan under the TH400. The transmission was primarily developed to improve fuel economy, which was achieved by the 30% overdrive capability, as well as the improved 3.06:1 gear ratio in 1st gear.

The first 700R4 had an input shaft with 27 splines, though this transmission design was prone to failure because it was unable to handle the load properly. In 1984, they introduced a 30 spline input shaft that was much stronger and reliable. The transmission typically has 1/4” pipe fittings on the passenger side for an improved cooling circuit. Later versions also use a pinned flare and o-ring design for the fluid cooling circuits. The 1987 and newer produced transmissions are considered to be refined and very reliable when performance is compared in 350 V8s in sports cars and trucks.

The physical swaps in the 700R4 transmission are straightforward to install, but the one component that confuses many owners and mechanics is the throttle-valve (T.V.) cable setup. If the T.V. cable is not set correctly, the transmission will underperform and cause its lifetime to be greatly shortened. Each time you adjust this component, you will need to reset the cable slider correctly while using the pressure gauge. This will ensure instantaneous pressure response with the new setup – this is critically important! If you operate the transmission with low hydraulic pressures, it can cause a transmission failure very quickly.

The front-facing TH700 unit is natively compatible with either the Chevrolet 90-degree “Small Block” & “Big Block”-patterned engines, including the V6, V8, I6 & Iron Duke I4 varieties. The General Motors 60-degree pattern engine can be mated to 60-degree style engines like those in the 3800, 3.4, and other engine families. These other transmission types are fairly rare since they were only produced for a few years for the Chevy S10 and Camaro with the 2.8L V6, prior to GM’s upgrade to the 4.3L V6 engine.

We offer 700R4 Transmissions with Torque Converter – Level 1, Level 2, Level 3, Level 4, & Level 5 as well as 700R4 Transmissions with Torque Converter – Level 2 for 4×4 vehicles on our website. Call us today or order directly through our website!

The transmission has the following dimensions and gear ratios:

Case to External HousingOverall LengthBell Housing to Mount
23 3/8″30 3/4″22 3/8″


Transmission1st Gear2nd Gear3rd Gear4th Gear Overdrive
Turbo 3502.521.521N/A
Turbo 4002.481.481N/A
700R4 /4L603.061.6310.7

General Motors Vehicle Models Using the 700R4 or 4L60E Transmissions:

1982-1992 Chevrolet Blazer/GMC Jimmy

1982-2005 Chevrolet Corvette

1983-1996 Chevrolet Impala and Caprice police specials equipped with 350 engines.

1983-1985 Oldsmobile 350 Diesel equipped models.

1983-2002 Chevrolet Camaro/Pontiac Firebird

1985-2005 Chevrolet Astro/GMC Safari

1991-1992 GMC Syclone

1991-1992 Oldsmobile Custom Cruiser

1989-2003 Chevrolet S-10/GMC S-15/Sonoma

1989-2005 Chevrolet S-10 Blazer

1989-2001 GMC S-15 Jimmy

1990-1996 RWD Cadillac Fleetwood/Cadillac Brougham/Cadillac Limo

2002-2009 Chevrolet TrailBlazer/GMC Envoy

1992-1993 GMC Typhoon

1984-2010 Chevrolet Suburban

1982-2012 Chevrolet Van

1994-1996 Chevrolet Impala

1994-1996 Buick Roadmaster

1982-2010 Chevrolet C/K

1993-2010 Chevrolet Tahoe/GMC Yukon

1999-2006 Cadillac Escalade

2002-2008 Chevrolet Avalanche

2003-2007 Hummer H2

2004-2007 Buick Rainier

2004-2012 Chevrolet Colorado/GMC Canyon

1988-2006 Holden Commodore

2004-2006 Pontiac GTO

2005-2009 Saab 9-7X