4L80E Overhaul Kit 1997-04, new and ready to install. Fits the 4L80E. Ships fast from the USA.
A 1997 to 2004 4L80E that slips on the 2-3 shift with a trailer behind it, flares into fourth on the highway, or leaves a dark, burnt smell on the dipstick has usually worn through more than one clutch pack. This new overhaul kit is built for that job in the center-lube 4L80E and 4L85E found in Chevrolet and GMC 2500 and 3500 pickups, Suburban 2500, Express and Savana vans and the Hummer H1. It is a complete bench kit rather than a reseal: BorgWarner friction plates, steel plates, a full soft parts set with every rubber seal and gasket, molded rubber clutch pistons, a new filter, front and rear bushings, and both the front and rear bands.
The 4L80E holds its gears with the overrun, forward, direct and fourth clutches, two one-way clutches, and a front and rear band. Every clutch applies through a piston sealed by rubber, fed by oil that passes Teflon or iron sealing rings on its way into a spinning drum. After enough heat, the frictions glaze, the steels heat-check and the seals harden, so apply pressure leaks away before it reaches the piston. This kit replaces all of those wear surfaces at once. Molded pistons are included because a bonded piston seal cannot be peeled off and replaced like a loose lip seal, and the two bands are included because a band reused after a burnt-fluid failure rarely holds for long.
The 1997 model year matters here. Transmission Digest explains that GM moved the cooler return from the pump to the center support that year to create center-gearbox lubrication, and redesigned several hard parts to match. This kit is matched to that later layout.
Rule out the electrical side first. A failing pressure control solenoid, a tired internal harness or a bad speed sensor can mimic a worn unit, and a scan for P0748, P0751-P0758 or speed sensor codes takes minutes. Our 4L80E pressure control solenoid symptoms guide walks through the EPC checks, and the 4L80E common problems and fixes guide covers the line pressure test that separates a leaking circuit from a burnt clutch. If the pan shows heavy friction debris and pressure is low in more than one range, an overhaul is the honest repair.
This listing is for the 1997-2004 4L80E and the 4L85E built on the same case, in Chevrolet, GMC and Hummer applications. The 1997 center-lube change separates this kit from the 1991-1996 units, so a pre-1997 transmission needs an early kit. Inside the 1997-2004 span there are still hard-part changes: Sonnax notes the valve body lube hole moved for 1997-2003, and 2004-later units use a late-style EPC solenoid with a silver canister, while Transmission Digest points out that 1999 and later rear carriers differ from the 1991-98 design. Those parts are reused, not supplied, so note what your unit has. If you are unsure, check the tag on the case or send us your year and VIN and we will confirm. You can see every part we carry for this transmission on the 4L80E parts page.
Electrical parts are the other half of a lasting rebuild. On a 1997-2003 unit, pair the kit with a new 4L80E pressure control solenoid and an internal wiring harness; on a 2004 unit, the 2004-up harness and solenoid kit matches the late EPC. If the intermediate sprag spins in both directions on the bench, replace it now while the unit is apart.
| Fits | 4L80E 1997-04 |
| 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.
Yes. It includes friction plates, steel plates, the front and rear bands, molded rubber pistons, front and rear bushings, a filter and a full set of seals and gaskets. Many lower-priced kits leave out the steels or the bands.
No. This kit is for the 1997 and later center-lube design. GM moved the cooler return to the center support in 1997 and changed several internal parts, so a 1991-1996 unit needs an early-style kit.
The kit is listed for both the 4L80E and the 4L85E built on the same 1997-later case. Confirm with your case tag or send us your year and VIN if you want us to check.
Plan on the pressure control solenoid and internal harness, since they cause many false rebuild symptoms. Also inspect the intermediate sprag, overdrive roller clutch, drums and pump, which are hard parts the kit does not include.
GM specifies Dexron VI for the 4L80E in its later owner manuals. Fill to the dipstick, run the engine, then set the final level with the fluid hot.
It is good practice to clear codes and drive the truck through light-throttle shifts for a few days so the control module adapts to the fresh clutches. Expect firmer shifts at first.
