Soft-parts overhaul kit for 1993-2003 GM 4L60E and 4L65E with both valve body gasket styles, check balls, pump seal, piston and servo seals.
Searching for a complete 4L60E reseal kit for a 1993-2003 Chevy or GMC truck usually turns up bags that leave you short a valve body gasket or a servo O-ring halfway through the job. This KP33900EF kit is built around that problem. Alongside the usual pan gasket and pump seal it carries both generations of upper and lower valve body gaskets, a full set of eight valve body check balls, and the small O-rings that are easy to forget until the unit is back in the truck and leaking. It suits the 4L60E and 4L65E in Silverado, Sierra, Tahoe, Yukon, Suburban, S10, Sonoma, Blazer and Camaro applications from those years.
The valve body decides which clutch or band gets oil and when, and the spacer plate and its two gaskets are the map between the valve body and the case passages. A gasket with the wrong hole pattern, or a missing check ball, sends oil to the wrong place and you get a harsh or missing shift on the first drive. The rest of the kit seals the routes that oil takes after it leaves the valve body: the Teflon rings on the shafts, the lip seals on each clutch piston, the 2-4 servo inner and outer O-rings, the accumulator piston O-rings, and the pump bolt O-rings that stop pressure escaping around the pump fasteners. The pump screens and filter seal O-ring keep the intake side clean and tight, so the pump is not pulling air on hard stops.
Frictions, steels and bands are not included.
A reseal makes sense when the unit leaks, engages slowly when cold, or slips on the 2-4 band because a servo O-ring has hardened, but the clutches still look good. Before ordering, drop the pan and look at what is in it. Our 4L60E 1-2 accumulator and shift feel guide helps separate a leaking accumulator seal from a worn valve, and the 4L60E shift solenoid guide covers the electrical faults that mimic slipping. A harsh shift with a P0748 pressure control code points to the EPC solenoid, not the seals.
Listed for GM 4L60E and 4L65E transmissions built from 1993 to 2003, and also for other GM makes that used those units. The two valve body gasket sets exist because the spacer plate pattern changed for 2001: lay each gasket over your plate and use the one whose holes line up exactly, then keep the other as a spare. If your transmission is 2004 or later, this is not the right kit. Send us your year and VIN if you are unsure, or browse the full 4L60E parts collection.
A 4L60E pump puller makes the teardown far easier, and if your truck has set a converter slip code, the Sonnax TCC regulator and isolator valve kit addresses the valve body bore wear a seal kit cannot reach.
| Kit number | KP33900EF |
| Fits | GM 4L60E, 4L65E (1993-2003) |
| Valve body gaskets | 1993-2000 and 2001-up styles |
| Check balls | 8 |
| Weight | 14 oz |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Whichever one matches your spacer plate. Lay each gasket over the plate and use the set whose holes line up with every passage.
No. The kit includes eight new check balls. Note where each original sat before removing the valve body and place the new ones in the same pockets.
If the slip comes from hardened 2-4 servo O-rings, yes, because the kit includes the inner and outer servo seals. A worn band or a servo pin bore that leaks will still need its own repair.
The listing includes the filter seal O-ring and pump screens, not a filter. Buy a new filter for the rebuild.
Dexron VI ATF. Check the level with the engine running and the fluid at operating temperature.
