6L90 Overhaul Kit 2006, new and ready to install. Fits the 6L90. Ships fast from the USA.
When a 6L90 in a Silverado or Sierra 2500HD, an Express or Savana van, or a 3500HD Suburban starts slipping under a trailer, flares between gears or leaves a pan full of black friction dust, the fix is a teardown, not a fluid change. This new master rebuild kit is catalogued for the GM 6L80 and 6L90 family from 2006 on, and it puts the four things every rebuild needs in one box: the overhaul gasket and seal kit, a friction clutch plate set, a molded piston set and a new filter.
Steel plates are not listed in this kit. If your steels are flat, unscored and not blue from heat, they can go back in after cleaning; if they are warped or heat-checked, step up to our 2007-up 6L90 overhaul kit with steels, or the 6L90 overhaul kit with shift and pump upgrades if you also want the valve body corrections.
The 6L90 is a clutch-to-clutch six-speed with five clutches and no bands. The control module times each shift by filling one clutch as another releases, using pressure control solenoids in the valve body. If a piston seal weeps or a sealing ring is worn, that clutch fills late and slips while it waits, so the module raises pressure to compensate and the next pack wears faster. Fresh seals and molded pistons restore the fill timing the module expects. Sonnax notes that the 4-5-6 clutch is a known weak point on these units because the backing plate flexes under high apply pressure, so inspect that pack and its backing plate closely while it is apart.
Pull the pan and look first. Clutch material in the pan means the packs are done and this kit makes sense; a clean pan with a shift complaint points elsewhere. Check line pressure against the module's commanded value before tearing down. A Gears Magazine case on a 2007 GMC 2500 found line pressure stuck at 65 to 70 psi after a rebuild, so pressure should be verified both before and after. Our 6L90 common problems guide covers the six failures we see most, and the 6L90 pump failure guide explains how to separate a pump or pressure regulator fault from worn clutches.
The kit is catalogued for 6L80 and 6L90 automatics from 2006 onward in Chevrolet, GMC, Cadillac, Hummer and Pontiac applications. The 6L90 itself is the heavy-duty version used in 2500HD and 3500HD pickups, vans and HD Suburbans, plus the Camaro ZL1 and Corvette Z06 and ZR1. ATSG documents about fifteen internal parts that differ between the 6L80 and 6L90, so count your old plates per pack and compare piston sizes against the kit before installing anything. If you are unsure, send us your year and VIN and we will check it. Every other 6L90 part we carry is on the 6L90 parts page.
| Fits | 6L90 2006 |
| Part type | Overhaul Kit |
| Condition | New |
| Brand | GM |
| 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 overhaul gasket and seal kit, a friction plate set, molded pistons and a filter. Reuse steels only if they are flat and show no heat discoloration, or choose our 2007-up kit that includes steels.
It is catalogued for both. Because ATSG lists about fifteen parts that differ between the two, count the plates in each of your old packs and compare them to the kit before installing, or send us your year and VIN.
The kit covers the whole 6L80 and 6L90 family, and 2006 is where that family's coverage starts. For a 6L90 truck or van, it applies to any year your unit was built.
Plan on steels if yours are heat-damaged, a cooler flush or new cooler, and a close look at the pump, stator support and valve body. Torque converter condition should be checked as well.
Dexron VI. After the rebuild, clear the transmission adaptive values and run the adaptive learn so the module relearns clutch fill times.
