GM 6L80/90 Archives - Transmission Digest
Potential causes of an overheated transmission: It’s not always what you think

If a transmission starts overheating, the root cause must be something to do with the transmission itself, right? Not always. The following are a few examples where the transmission was not to blame. Exhibit A: GM 6L80/90 The first overheating case comes from GM 6L80 and 6L90 transmissions equipped with a thermal bypass valve in

Sonnax introduces remanufactured TEHCMs for 6L80/90

Sonnax has introduced a new line of remanufactured TEHCMs for GM 6L80 and 6L90 transmissions. Each unit is fully electro-hydraulically tested to comply with OE performance and VIN-blanked for easy programming to any applicable vehicle, the company says. Coverage includes the following:

Raybestos introduces new 6L80/90 clutch packs

Raybestos has introduced a new GPZ performance friction clutch pack for the GM 6L80 and 6L90, model years 2006 and on. According to the company, this clutch pack contains upgraded friction components manufactured with a blend of GPZ high energy fibers for ultimate stress and high temperature durability. This kit includes 6 GPZ565 1-2-3-4, 6

Transtar highlights cooler flow bypass kit for GM, Allison

Transtar highlights the TransGo cooler flow bypass kit for GM 6L80, 6L90, 8L45 and 8L90 models as well as Allison 1000 transmissions. Years covered range from 2014 to 2022. According to the company, features of this kit include: Provides all-time cooler flow regardless of temperature; Prevents overheating; Reduces transmission fluid temperature; Eliminates thermostatic assembly; Allows

Superior Transmissions introduces pump components for GM 6L transmissions

Transtar highlights a new line of Superior Transmissions pump components that fit all variations of GM 6L45/6L50 and 6L80/6L90 units. According to the company, these can be installed in conjunction with the STL012 pump upgrade kit or any O.E. Main Pressure Regulator valve, as well as all aftermarket P.R. valve repair kits, including oversized internal

Easy fixes to common transmission problems

Transmission makers are always throwing the repair industry curveballs. The challenges seem endless. Sometimes manufacturers will let us know of changes they are doing, while other times they let us figure it out as we go. I would like to go over a few examples we’ve encountered that may help you on a simpler installation

Dealing with GM 6L series rebuild issues

During a rebuild of a GM 6L80 transmission, while the valve body was being serviced, an incorrect spacer plate was accidentally used. This blocked supply pressure to the 3-5-R regulator valve which prevented the 3-5-R clutch from applying. One of the more significant changes made to the valve body for 6L80 series transmission is related

Watch: The critical gasket for the GM 6L80

Calling it the “gift that keeps on giving,” Dave Hristko, technical product specialist for Transtar, uses this video from the Transtar Garage Studio to talk about the GM 6L series. “But there’s something that you can’t get from GM that I believe is seriously critical on this unit,” he goes on. “And that’s the stator

GM 6L80, 6L90 Output Planetary Lube Dam

Avoid failures and comebacks by cleaning the lube passages and installing the new Sonnax output planetary lube dam (p/n 104584LP). The output planetary assembly in GM 6L80/90 transmissions has a lube dam, or cover, that directs lube oil flow to the planetary lube feed passages. Over time, sludge buildup can occur, which chokes off lubrication

6L80 / 6L90 Pump Stator to Pump Gasket Upgrade

TransTec recently announced that it has replaced the paper pump stator to pump gasket for 2006-Up 6L80/6L90 applications with a new rubber-coated metal gasket. This new design will eliminate any chance of blowout or leakage along with minimizing pump stator to pump runout issues. The company says the updated kits are in stock and available

SX-23-68 Repair Ring for GM 6L80/90

Tri Component’s SX-23-68 repair ring (for GM 6L80/90) is used to renew the surface of the clutch plate and to compensate for machining and wear of the plate and front cover. It is designed to re-establish the correct clearance. The repair plate is welded to the clutch plate. The final dimension is established by machining

Repair Ring for GM 6L80/90

The repair plate is welded to the clutch plate. The final dimension is established by machining the plate after welding.