8L90 Transmission Parts
8L90 transmission parts for 2015+ GM half-ton and full-size SUV applications. The 8L90 is GM's 8-speed automatic, used in Silverado/Sierra 1500, Tahoe, Yukon, Suburban, Cadillac Escalade, and Corvette C7/C8 applications behind 5.3L, 6.2L, and other LT-series engines.
Known for early-life shudder and harsh shift complaints — Dexron HP fluid (not Dexron VI) is mandatory. The 8L90 is sensitive to fluid spec; using the wrong fluid will cause shudder within a few thousand miles.
We stock rebuild kits, friction packs (Alto, Raybestos), Sonnax valve body kits, master rebuild kits, torque converters, solenoid packs, valve body components, filters, pan gaskets, and individual hard parts for the 8L90. Performance upgrades for tuned 6.2L LT applications including reinforced clutch packs and updated valve body components.
Service interval: drain and refill every 50,000 miles with Dexron HP, even though GM advertises "lifetime fill." Lifetime fill is marketing — every transmission benefits from fluid changes. Free shipping over $70. Same-day shipping on in-stock parts.
