The 6L80 transmission is a GM 6 speed automatic transmission that was introduced for the 2006 model year, in order to meet the government mandated fuel economy targets without sacrificing overall vehicle performance. It features clutch-to-clutch gear changes that did not involve transmission bands, and could be manually controlled by the driver with the gear selector or buttons on the column shifter. This was also one of the first GM automatic transmissions that was designed to be completely electronically controlled, and received all of its inputs from a 32-bit controller/6L80 TEHCM that was integrated into the valve body assembly.
What Transmission Do I Have?
What vehicles have 6L80 transmission?
- 2009 – 2021 Chevrolet Silverado
- 2009 – 2021 Chevrolet Suburban
- 2009 – 2015 Chevrolet Tahoe
- 2008 – 2013 Chevrolet Avalanche
- 2009 – 2015 Chevrolet Camaro
- 2006 – 2014 Chevrolet Corvette
- 2011 – 2017 Chevrolet Caprice PPV
- 2014 – 2017 Chevrolet SS
- 2009 – 2021 GMC Sierra
- 2009 – 2015 GMC Yukon
- 2009 – 2021 GMC Yukon XL
- 2007 – 2015 GMC Yukon Denali
- 2008 – 2009 Hummer H2
- 2007 – 2015 Cadillac Escalade
- 2007 – 2009 Cadillac STS & STS-V8
- 2006 – 2009 Cadillac XLR-V
- 2008 Pontiac G8
6L80 Transmission Applications
The 6L80 transmission was designed from the ground up to be a fully electronically controlled gearbox. It replaced the 4–speed 4L80/4L85 transmission and ditched that gearbox’s one – way clutches for a more efficient clutch-to-clutch arrangement. Starting in 2005, the 6L80 was used in RWD/AWD/4WD applications, and paired with the following engines:
4.3 L V-6
5.3 L V-8
6.0 L V-8
6.2 L V-8
Common 6L80E Transmission Problems
Reverse fails to engage
If you selected Reverse and your vehicle still won’t move, then it’s possible the park prawl (the little metal piece that stops your vehicle from rolling when you shift into Park) or one of the clutches has become damaged.
Slipping between gears
If you experience slipping in Reverse, or between 2nd and 3rd gears, then it’s likely that the 1-2-3-4 or 3/5-R clutch drum has developed a crack, which will require replacing both the drum and the bearing.
Slipping in first gear
If you have difficulty getting your vehicle to move from a dead stop, then it is possible that one of the solenoids is stuck in the ‘off’ position inside of the valve body.
Buy a Used 6L80 Transmission
If you wanted to save some money, you could go down to the local junkyard and buy a used 6L80 transmission. But keep in mind, it’s coming out of a wrecked or otherwise totaled vehicle. This means you don’t know how it was maintained, if it was abused or what the condition of the internal components really are. So you have no way of knowing if you are going to get 30 miles or 30,000 miles out of it. And that replacement warranty you get from the junkyard isn’t going to cover the labor cost that you’ll have to pay a mechanic to install a replacement transmission if the first used 6L80 breaks.
Buy a Rebuilt 6L80 Transmission
If you don’t want to risk future problems from a used transmission, then you might consider buying a rebuilt 6L80 transmission from a mechanic or transmission shop. In this scenario, they basically take your existing transmission and replace all of the main seals clutches and other “wear parts”. A rebuilt 6L80 transmission is obviously better than a used one. However, most mechanics and repair shops don’t have the experience and equipment to inspect every single component for signs of damage, warping and any other condition that might cause the parts to fall below the original manufacturer’s specifications. Plus that rebuilt transmission warranty may only be honored by a few local transmission shops.
Buy a Remanufactured 6L80 Transmission
Unlike a rebuilt 6L80 transmission, a remanufactured 6L80 transmission has been completely disassembled and then re-engineered on an assembly line. Each component is inspected, cleaned, and reconditioned by a technician that specializes in that particular stage of the process. All of the critical elements including the case, gears, valve body, shafts, pumps, and the torque converter are tested to ensure that they meet original equipment (OE) tolerances and standards. And any part that doesn’t meet the original specifications is either machined until it does or replaced with a brand new part.
Once all of the components meet specification, they’re sent down an assembly line and the transmission is reassembled. The reman 6L80 transmission is then put on a dyno machine which simulates real-world driving through a software program called C.A.R.S. This allows any leaks and imperfections to be discovered and dealt with before the transmission leaves the factory.
Another benefit of a remanufactured transmission are the updates and upgrades it receives. Once a certain vehicle model has been in production for a few years, small issues with the design are discovered and solutions are implemented. It may be more robust friction materials, stronger seals, stiffer springs, or number of other things. These changes are immediately applied to the new models still in production, and Technical Service Bulletins (TSB’s) are sent to dealers so they know how to deal with problems that may arise. Transmission remanufacturing companies like Street Smart Transmission also get these TSB’s, and implement the changes on their assembly line as well.
If you’d like to learn more about getting a remanufactured 6L80 transmission from Street Smart Transmission, click here.
What Transmission Do I Have?
