4L80E Overhaul Kit 1991-1995, new and ready to install. Fits the 4L80E. Ships fast from the USA.
The 1991-1995 4L80E sits behind big gas V8s and the 6.5 turbo diesel in Chevy and GMC 2500 and 3500 pickups, Suburban 2500s and G-series vans, and after thirty years most of them have seen real work. When one of these trucks starts slipping out of third on a grade, engages Drive with a long pause, or pushes fluid out of the vent after a tow, this new overhaul kit gives you the plates and soft parts to rebuild it: friction plates, steel plates, sealing rings, metal-clad seals, gaskets, O-rings and a filter.
The 4L80E is a TH400-based gear train with an overdrive section added in front, so it has more clutch packs than the old three-speed: overrun, forward, direct and fourth. Line pressure from the pump is routed through sealing rings into each rotating drum, where it pushes a piston against a stack of frictions and steels. On these early units the cooler return still feeds lube through the pump. Over the years the frictions thin out, the steels pick up heat spots, and the rings and lip seals stop holding. The kit replaces those wear parts in every pack so each clutch gets full pressure and full clamping surface again. Drums, pistons, bands and bushings are reused if they pass inspection.
Early 4L80E trucks have a few problems that look like worn clutches but are not. On 6.5 diesels from 1994 on, Transmission Digest explains that the accelerator pedal position sensor is the main input for both fueling and transmission line pressure, so a faulty pedal sensor can cause low line pressure and slipping. Another Transmission Digest bulletin traces gear-ratio-error codes on some 4L80E trucks and vans to an output carrier without a speed sensor exciter ring. Our 4L80E speed sensor symptoms guide covers that check. Rule those out, then test line pressure in each range as shown in the 4L80E Silverado 2500 common problems guide. Low pressure across several ranges plus clutch debris means the unit needs this kit.
This kit fits the 4L80E built from 1991 through 1995 in Chevrolet and GMC trucks, Suburbans and vans, gas or diesel. It does not fit the 1997-later center-lube design. The early years themselves were not identical. Sonnax notes that the screw-in transmission temperature sensor was used only in 1991, and ATRA reports that GM introduced a new pressure control solenoid, shift solenoids, harness and connector in 1994. Those electrical parts are not in this kit, but they decide which replacements you order. If you are not sure which version you have, send us the year and VIN and we will match it. The full range of early parts is on our 4L80E parts page.
| Fits | 4L80E 1991-1995 |
| 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.
The kit is listed for 1991-1995. The same early, non-center-lube design runs through 1996, but 1996 units have different low/reverse servo hardware. Send us your year and VIN and we will confirm before you order.
Yes. The transmission internals are the same 4L80E, gas or diesel. On a 1994-later 6.5, check the accelerator pedal position sensor first, because it controls line pressure.
Friction plates, steel plates, sealing rings, metal-clad seals, gaskets, O-rings and a filter. Bands, bushings and pistons are not included.
It is a good idea on a high-mileage unit. Match the solenoids to your year: 1994 introduced new pressure control and shift solenoids, a new harness and a new connector.
Dexron VI, the fluid GM now specifies for the 4L80E. Set the final level on the dipstick with the fluid hot.
