8L90 Pump 2015, new and ready to install. Fits the 8L90. Ships fast from the USA.
This listing is a complete pump-and-rebuild package for the GM 8L90 eight-speed, 2015 and later, not a bare pump housing. It pairs OEM GM pump hardware with a full banner rebuild kit and a valve body shift kit, aimed at the 8L90 in V8 Silverado and Sierra pickups, Yukon Denali, Escalade, Camaro SS, Corvette and CTS-V. It is for the rebuilder who has a unit on the bench with low line pressure, a no-move, a chain that lifts off its sprockets, or burnt clutches, and wants the pump drive, the soft parts and the pressure control fixed in one order.
The 8L90 pump is not driven directly by the converter hub. It sits off-axis in the valve body area and is turned by a chain from the converter-driven sprocket. GEARS Magazine describes it as a binary vane pump with two pumping chambers and no vane guide ring, so the vanes rely on oil pressure to track. That design is efficient but sensitive: a worn chain, a dry pump on first start or a worn pressure regulator bore all show up as pressure problems throughout the transmission.
Put a gauge on line pressure first. Low pressure in every gear points to the pump drive or regulator; high or erratic pressure points to valve body wear, covered in our 8L90 valve body symptoms guide. With the pan off, check the chain: Transmission Digest notes GM publishes no wear spec, but the chain has a 1/2 inch pitch, so ten rivet pitches should measure 5.0 inches, and roughly 5.075 inches is a sensible 1.5 percent wear limit. A chain that kinks when rotated slowly on the sprocket is worn. Our 8L90 pump failure guide covers the full diagnosis.
The package is listed for 2015 and later 8L90 (RPO M5U) units. GM changed the 2-3-4-6-8 pistons and seals for 2018, and later trucks with Dynamic Fuel Management received valve body and S4 changes, so send us your year and VIN before ordering and we will confirm the pistons, seals and shift kit valves suit your build. It does not fit the 8L45. If you only need soft parts, the standalone 8L90 banner rebuild kit costs less. All 8L90 parts are on the 8L90 collection page.
| Fits | 8L90 2015 |
| Part type | Pump |
| Condition | New |
| Brand | TransGo |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. It includes the OEM GM pump chain and sprockets plus the pump gears and stator support assembly, along with a banner rebuild kit and a shift kit. It is a rebuild package built around the pump drive.
Ten rivet pitches on a new chain measure 5.0 inches. Around 5.075 inches is a reasonable wear limit, and a chain that lifts off the sprockets or kinks when rotated slowly should be replaced.
The off-axis pump often fails to prime. Bench prime it with ATF before installation, pre-fill the converter, and check the pressure regulator valve orientation.
It is listed for 2015 and later, but pistons, seals and valve body parts changed over the run. Send your year and VIN and we will confirm fitment.
DEXRON HP only. GM lists a 7.4 quart service refill; a dry rebuilt unit needs more.
