8L90 Banner Rebuild Kit 2015, new and ready to install. Fits the 8L90. Ships fast from the USA.
This banner rebuild kit is built for the GM 8L90 (RPO M5U) eight-speed starting with the 2015 model year. The 8L90 sits behind the V8s in Silverado and Sierra 1500 pickups, the Yukon Denali and Escalade, the Camaro SS, Corvette and CTS-V. Owners land here when a high-mileage or hard-towed unit starts slipping, burns its fluid, or throws ratio codes that a fluid flush and relearn will not clear.
The kit combines a complete overhaul gasket and seal set with BorgWarner friction clutches, replacement pistons and a new transmission filter. The overhaul set brand can vary by availability, but it covers the full case, valve body and piston sealing job. Including pistons matters on this transmission, because GM changed the 2-3-4-6-8 clutch pistons after cracking problems on early units.
The 8L90 uses four planetary gearsets and five clutches to make eight speeds, and GM rates the gearbox at 665 lb-ft. Each clutch is applied by a sealed piston and controlled by its own variable force solenoid, so shift quality depends on two things the kit restores: tight piston sealing so apply pressure is not lost, and frictions whose material and thickness match what the TCM calibration was written around. GEARS Magazine stresses that off-spec clutch material produces shift complaints no relearn can fix, which is why OE-grade BorgWarner frictions are the right choice here.
The most common 8L90 complaint is a 25 to 80 mph shudder, and GM bulletin 18-NA-355 fixes most of those with a fluid exchange to Mobil 1 Synthetic LV ATF HP, so do that first if shudder is your only symptom. Harsh shifts can also come from a worn pressure regulator or signal accumulator bores in the valve body, which a valve body repair kit addresses without a teardown. Our 8L90 common problems guide walks through that order, and the 8L90 rebuild cost guide shows where the money goes once a rebuild is confirmed.
The listing covers 2015 and later 8L90 units, but this transmission changed mid-run, so check before you order. Starting in 2018, GM updated the 2-3-4-6-8 clutch piston, dam piston and their seals, and early and late D-rings are not interchangeable (for example GM 24259281 for 2015-2017 versus 24283348 for 2018-up). The 1-3-5-6-7 drum also comes in a four-clutch A version and a five-clutch B version, identified by the code next to the QR mark on the drum, so the friction count must match your drum. Send us your year and VIN, or the drum code, and we will confirm the kit matches. This kit is not for the 8L45 in the Colorado and Canyon; that unit uses the 8L45 banner kit. See all 8L90 parts on the 8L90 collection page.
If you need steels or bushings, our 8L90 overhaul kit for 2015-2017 is the matching early-year seal set reference.
| Fits | 8L90 2015 |
| Part type | Banner Rebuild Kit |
| Condition | New |
| Brand | Borg Warner |
| Ships | From the USA |
| Warranty | 1-year |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It is listed for 2015 and later 8L90 units. Because GM changed the 2-3-4-6-8 pistons and seals in 2018, send your year and VIN so we can confirm the pistons and D-rings match your build.
The kit includes frictions, pistons, the overhaul gasket and seal set and a filter. Steels are reused if flat and not heat-marked, or replaced separately.
Usually not on its own. Most 8L90 shudder is covered by GM bulletin 18-NA-355 and fixed by a fluid exchange to Mobil 1 Synthetic LV ATF HP. Rebuild when the clutches are actually slipping or burnt.
Look next to the QR code on top of the 1-3-5-6-7 drum. 8L90A drums use four clutches and 8L90B drums use five.
DEXRON HP only. GM lists 7.4 quarts for a service refill; a dry rebuilt unit takes more, so set the level hot per the service procedure.
