General Motors 8L45/8L90 Transmission Archives - Transmission Digest
Alto introduces friction clutch, friction ring for GM 8L90E

Alto has introduced two new products for the General Motors 8L90E transmission: a torque converter friction clutch and a torque converter friction ring. The GM 8L90E torque converter friction clutch (above left) has a x30 bent tooth design and is meant for 2015-2019 6.2L engine applications. GM 8L90E torque converter friction ring (seen above) has a

GM 8L45, 8L90 Oversized Converter Feed Limit Valve Kit & Tool Kit

Bore wear or a stuck converter feed limit valve in GM 8L45/90 transmissions can result in converter overheat, incorrect TCC apply or release, inadequate lube and cooling, and converter over-pressurization. Reaming the bore and installing this new Sonnax kit will recover hydraulic control, renew TCC and lube performance and protect against premature wear for lasting

8L45/90 Pressure Regulator & Shuttle Valve Kit

This critical shuttle valve spool, available from Transtar (p/n S154741PK), is made 30% longer than OE for added sealing and durability. These drop-in Zip Valve parts install quickly and easily. The valve kit includes the Pressure Regulator Valve, Spring, Shuttle Valve, and Shuttle Sleeve. Was this content valuable? Submit Cancel Thanks for your feedback!

GM 8L45/90 Converter Feed Limit Valve Kit

Bore wear or a stuck converter feed limit valve in GM 8L45 and 8L90 units can result in converter overheat, incorrect TCC apply or release, inadequate lube and cooling and converter over-pressurization. This new drop-in Zip Valve kit from Sonnax (p/n 154740-19K) recovers hydraulic control for proper performance and protects against premature wear for lasting results.

GM 8L45/90 Pressure Regulator & Shuttle Valve Kits

Wear at the pressure regulator casting bore and/or shuttle valve sleeve in GM 8L45/90 transmissions can cause multiple issues including high line pressure, harsh shifts, low cooler flow, loss of lube oil and overheating.

GM 8L45, 8L90 Signal Accumulator Piston Kit

Sonnax has a new drop-in Zip Valve product: signal accumulator piston kit (p/n 154740-06K). Including four piston sets that fit any of seven locations in GM 8L45 and 8L90 units, this kit allows bores to be reconditioned quickly and easily with no reaming required. The hydraulic integrity of the VFS signal pressure circuits are re-set.

GM 8L45, 8L90 O-Ringed End Plug Kit

Sonnax introduces a new drop-in Zip Valve product: an O-ringed end plug kit (p/n 154740-17K). This easy-to-install kit puts an end to leaks, restores hydraulic integrity, and renews shift operation in GM 8L45 and 8L90 transmissions.  Was this content valuable? Submit Cancel Thanks for your feedback!

GM 8L45, 8L90 O-Ringed End Plug Kit

Sonnax has introduced a new drop-in Zip Valve product: O-ringed end plug kit (p/n 154740-17K). This easy-to-install kit puts an end to leaks, restores hydraulic integrity and renews shift operation in GM 8L45 and 8L90 transmissions. Was this content valuable? Submit Cancel Thanks for your feedback!

Video: GM 8L45/90 Part II

In Part II of our look at GM’s 8L45/90 eight-speed, Mike looks at some of the ongoing problems of these transmissions.

Video: GM 8L45/90 Part I

Various aspects of the GM 8L45 / 90 eight-speed RWD models will be addressed.

Video: GM 8L45/90 Issues

GM upgraded the transmission stator support and case cover to remedy the problem.

Picking Up Bad Vibrations

Quite a lot has been written and many technical classes have been put on regarding the General Motors 8L45/8L90 family of transmissions. We are now seeing opportunities to put that information to use.