6l80e length

Motor vehicle

The 6L80 (and similar 6L90) is a six-speed automatic transmission built by General Motors at its Willow Run Transmission plant in Ypsilanti, MI. It was introduced in late 2005, and is very similar in design to the smaller 6L45/6L50, produced at GM Powertrain in Strasbourg, France. It features clutch to clutch shifting, eliminating the one-way clutches used on older transmission designs. In February 2006 GM announced that it would invest $500 million to expand the Toledo Transmission plant in Toledo, Ohio to produce the 6L80 in 2008. Torque rating 440 ft/lb (600 nm). 6L90 520ft/lb (700 nm).

Specifications[edit]

Technical Data[edit]

Applications^[1][edit]

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The 6L80 Hydra-Matic transmission is a 6 speed automatic transmission  manufactured by General Motors.  It was created to help GM meet ever more demanding CAFE regulations on their vehicles.  By utilizing more gearing, the 6L80 keeps the car in it’s power band longer, improving the MPG of the vehicle between 4-7% (over the previous generation fours speed transmissions) depending on the configuration of the vehicle that it’s in.

It began replacing the 4L60E transmission in many vehicles starting in the 2006 model year. The 6L80E went mostly into large vehicles with V8 motors.  For the most part, this transmission has been phased out by the 8L90E already, but is still in prodution.

Unlike the 4L60E and 4L80E, the 6L80 is not always referred to as with the E on the end because it’s been over 25 years since the last non electronic GM transmission has been in production.

The 6L80 was used in trucks, particularly in the GMT 900 platform.  The exceptions to this would be the 2006-2014 Corvette,  2006 G8, 2010-2015 Camaro, and the Chevrolet SS.  In fact, the only 2017 model year vehicle that still comes with this transmission is the Chevrolet SS.

6L80E Specs

The 6L80 is a robust transmission and can handle a ton of power.  In fact the input torque rating is 440 lb. and it can handle a total gross vehicle weight of 8,600 lb, which makes it a great transmission for LS swaps with no modification needed whatsoever.

It’s a longitudinal transmission (that’s what the L in 6L80E stands for).  This means that it’s designed for rear wheel drive vehicles only.  It has a line pressure tap for diagnostic purposes.

Here are the basic specs for the 6L80E:

6L80E Gear Ratios

The 6L80E uses four under drive gears and two overdrive gears.  It does not have a direct 1:1 ratio like the 4L80E and 4L60E, which is worth noting.  The 6L80E’s gear rations are as follows:

6L80E Identification

There are two super easy ways to tell whether or not the transmission is a 6L80E.  Which one you use is going to depend on whether or not the transmission is in or out of the vehicle.  If the transmission is in the vehicle you can use the RPO tag in the glove compartment.  If you know the RPO code for the transmission you are golden.  It’s like where’s Waldo.  Just keep scanning it until you find the one you are looking for.

GM Transmission RPO Codes:

• 6L80–  MYC
• 6L90-   MYD
• 4L60E- M30
• 4L60E- M30
• 4L60E- M30
• 4L65E- M32
• 4L80E- MTI

Every modern GM vehicle has one of these sheets in its glove compartment. Use it to verify the vehicle has a M30 4L60ENow, if the transmission is out of the vehicle (or if you don’t trust a sticker), the 6L80E has an 18 bolt case.  That’s more than almost any other GM automatic transmission.  It looks nearly identical to the 6L90.  For all practical purposes, these two transmissions are completely interchangeable.

The 6L90 has a beefier set of gears and many internal upgrades.  Like most GM automatic transmissions, the easiest way to tell them apart is by using the pan gasket.  Conveniently, the main transmission that the 6L80E is going to be confused for all have a different number of pan gasket bolts.  See the pictures below to help you tell if you have the right transmission.

They all look really similar, so make sure that you bother to count the pan gasket bolts, especially if you have an untrained eye.

Conclusion

That’s pretty much all that’s to it.  If you have any questions that I may be able to help you with, drop a comment or contact me.

The Novak Guide to the

Introduction

The GM Hydramatic 6L80 transmission heralds a significant change in the design of automatic transmissions at General Motors. All previous GM automatic transmissions were virtually all based on hydraulic controls, and received increasing electrical elements as they modernized. The 6L80 was, from the ground up, developed as an electric over hydraulic transmission with microprocessor control.

The 6L80 began manufacture in 2005 for release in 2006 model year GM vehicles, persisting until at least 2016 in both 6L80 and 6L90 versions.

Development

The 6L80 would have big shoes to fill, with legendary predecessors like the TH400, 4L80E and 4L60E transmissions. But, GM had been in transmission limbo, so to speak, needing a modern transmission to fill the duty gap between the excellently versatile 4L60E (and its tougher 4L65 & 4L70 variants) and the Allison transmissions. GM was still using their trustworthy 4L80E transmissions for heavier duty use, which was essentially a 1960's technology TH400 with added 1990's overdrive and electronic controls.

A horsepower revolution spawned by GM's increasingly powerful Gen. III+ V8 engines and their aggressive platforms such as the Cadillac STSV, XLRV, various trucks and SUV's and the venerable Corvette. The 6L80 was approved for use in these vehicles weighing up to 8600 lbs. or gross weight of 14,000 lbs.

Specifications

The 6L80 denotes that the transmission is a 6-Speed, Longitudinally mounted, and for 8000 lbs. vehicle weights. It's RPO code is "MYC" and it is domestically manufactured in GM's Ypsilanti, Michigan plant. Newer to the transmission world is its use of direct clutch-to-clutch shifting and the total lack of bands. Because of this, the 6L80 - despite having two or three more gears than its predecessors, is unexpectedly short in length.

Maximum engine input torque for the 6L80 is 440 ft. lbs. and the maximum output torque is 664 ft. lbs. The case is a cast aluminum alloy.

The 6L80 features a generously deep first gear for an automatic, making for favorably powerful starts from a standing stop. The transmission lacks a direct-drive, but features two overdrive gears. The gearing spread is a very capable 6.04, with ratios in each gear as follows:

First: 4.02, Second: 2.36, Third: 1.53, Fourth: 1.15, Fifth: .085, Sixth: 0.67, Reverse: 3.06

Recommended fluid is Dexron VI and it typically accepts a 10 quart thru 12.6 quart fill depending on its application. It features a dry weight of ~195 lbs. and can weigh up to ~230 lbs. full. Like earlier automatics, the 6L80 features one line pressure tap available for testing and diagnostic purposes.

The torque converter is a fluid turbine drive and - like those on its predecessor transmissions, the TH350C, 700R4, 4L60, and 4L80E - features a lock-up pressure plate for direct mechanically coupled driving from the engine crank. As with earlier Hydramatics, the 6L80 will accept either the 258mm or 300mm torque converters.

The 6L90

Within only a year, GM had introduced an even stronger variant of the 6L80; the 6L90, RPO code MYD. This version is 1-3/8" longer and about 25% of its internal parts differ. Engine torque rating increases minimally, but the output torque rating of the transmission jumps up by nearly 220 ft. lbs. to 885 ft. lbs., with a respectable GVW of 15,000 lbs. and GCVW of 21,000 lbs.

To handle the increased output torque capacity, the 6L90 departed from the long-standing GM 32 spline specification output shaft of the 6L80 and went to larger diameter 29 spline for most truck applications. However some 2wd vans and HD truck versions had a 36 spline. Be aware of your output shaft version before proceeding with any adaptation.

Technology

The 6L80 / 6L90 uses three-way solenoids and variable bleed solenoids for improved shift quality. The transmission is automatically shifted featuring performance algorithms to minimize upshifts during closed throttle driving to prevent unnecessary shifting. It can also be controlled under DSC, or Driver Shift Control, e.g., "tap shifting". Maximum shift speed is 6500 RPM.

The Transmission Control Module (TCM) is an adaptive learning, 32-bit computer integrated into the valve body of the 6L80 / 6L90 and communicates with the Engine Control Module via the onboard vehicle CAN bus network. This is both a return to and a departure from previous automotive control systems in the industry in that earlier electronic transmissions used a separate control module, later to be integrated into the Engine Control Modules which were thus termed Powertrain Control Modules. Now, the high-speed CAN network allows a high rate of data sharing between the units to achieve a collaboration between both engine and transmission functions. The TCM is actually even programmed to adjust its operation for transmission clutch wear.

While not new to the 6L80, it uses an Input Speed Sensor to monitor input speeds to compare against engine speed and Output Shaft Sensor speed, using this data to adjust shift speeds under instantly detectable conditions. The transmission can also signal the engine to drop power during a shift if there's a possibility of clutch damage. Shift stabilization is achieved through these and similar strategies. Grade braking and clutch line pressure (for greater holding power) are additionally great features that are activated by Tow / Haul mode on the truck platforms.

Engine Compatibility

The 6L80 is a modular transmission, featuring removable bellhousings and tailhousings for interchangeability with the GM 90 Degree engines and other potential engines in the future.

While the 6L80 is generally mechanically compatible with Chevrolet and GM Gen. III+ engines, due to its advanced control strategy, the 6L80 is functionally compatible only with Generation IV GM engines and their matched Engine Control Modules.

Electronic challenges exist when mixing and matching the 6L80 as they must be matched to their particular engine. In a similar vein, GM Gen. IV engines do not always take kindly to other transmissions such as manuals (essentially no longer available from GM), and most automatics that predate the 6L80. Special engine computer programming strategies may be required.

Jeep Conversions

The 6L80 is doubtless a very successful OEM transmission, and a terrific conversion transmission in the right Jeeps and situations. However, it is a long transmission and is not compatible with short-wheelbase Jeeps such as the CJ5.

Transfer Case Adaptability

The 6L80, adapted and ready for a Jeep Dana 300 and the Jeep New Process transfer cases.

This transmission makes an excellent conversion transmission due to its adaptability into most Jeeps longer than CJ5s. Both 2wd and 4wd versions of the 6L80 can be used equally well, and there are no inherent advantages to either one once you have installed our adapter assembly.

2wd transmissions feature conical shaped tailhousings and an output yoke, which are replaced with a typically shorter 4wd style output shaft of varying lengths and spline counts, depending on the application. The HydraMatic can be adapted to the popular Jeep transfer cases, including the:

• Dana 300, 1980-1986

• New Process Jeep 208, 219 & 229

• New Process Jeep 231, 242 & 249

Essentially all factory GM 4wd applications available with an OEM configured 6L80 have adapters and transfer cases that are prohibitively long for a Jeep, and transfer cases whose sizes and gearing fall short of desirable for most Jeep applications.

GM Vehicles Featuring the 6L80 Transmission

• Chevrolet Corvette
• Cadillac XLR
• Cadillac STS
• Cadillac XLRV
• Cadillac STSV
• Chevrolet Avalanche
• Chevrolet Silverado
• Chevrolet Suburban
• Chevrolet Tahoe
• GMC Sierra
• GMC Yukon
• Cadillac Escalade
• H2
• Pontiac G8

Summary

The 6L80 in its transaxle version for the Corvette

The 6L80 has surprised us power transmission aficionados with its wholesale adoption of new and very different technologies. What is most welcome about it is that it is a very durable, functional and impressive transmission assembly and appears to have a terrific prospect with GM and the aftermarket community. 

Dimension "C" is the distance from the bellhousing to the center of the transmission mounting pad. Note: The mounting pad is usually a part of the extension housing, but the graphic shows it on the maine case. this means that dimension "C" is usually longer than dimension "B".

Powerglide (bellhousing pattern - Chevrolet, Fit-all)

TH350 (bellhousing pattern - Chevrolet, BOP, Fit-all)

TH400 (bellhousing pattern - Chevrolet, BOP)

TH200-4R (bellhousing pattern - BOP, Fit-all)

TH700-R4 /4L60 (bellhousing pattern - Chevrolet)

* An extension housing p/n 8673406 (old p/n 24214689) is available for the TH700R4/4L60 transmission that moves the rear transmission mount to the same position as a TH400 (short-style 4" tail) or TH200-4R transmission. This 7-3/8" long extension housing can eliminate transmission crossmember modifications when replacing a TH400 or TH200-4R transmission with a 4L60 assembly.

4L60E (bellhousing pattern - Chevrolet/removable)

4L60E / 4L65E (w/ removable bellhousing) All LS1 Type

4L80E 1991-Later (bellhousing pattern - Chevrolet)

6L80E 2006-Later (w/ removable bellhousing)

6L90E 2006-Later (w/ removable bellhousing)

Splines (output shaft)    Pan Bolts (number of)

Chevrolet Transmission Ratios

Transmission Fluid Capacity (see also capacity of fluid in the converter here)