The valve body kit that firms up the lazy, slipping shifts a stock 4L60E is known for, and cures the mushy TCC apply before it burns the converter clutch.
The TransGo SK 4L60E is the shift kit rebuilders have used for decades on the GM four-speed behind small-block and LS engines in Chevrolet Silverado, Tahoe, Suburban and Camaro, GMC Sierra and Yukon, and the rest of the rear-drive lineup. If your search started with TCC shudder, a P1870 code, a harsh 1-2 upshift, a 2-3 flare or a 3-4 clutch pack that burned up after a rebuild, those are exactly the complaints TransGo lists for this kit. It is part number TGOSK4L60E, fits the 4L60E from 1993 on, and ships from the USA.
TransGo designed this kit to recalibrate the 4L60E's entire accumulation system rather than one valve. The 1-2 and 3-4 accumulator springs, second servo springs, pressure regulator springs and actuator feed limit spring all change together with a slight increase in line pressure, so the clutches and 2-4 band stroke and apply quickly instead of slipping through every shift. The kit also adds an EPC screen and an oversized 1-2 checkball. The standout piece is a hardened steel TCC regulator and isolator valve with longer lands. GM's original valve wears its bore, the converter clutch loses apply pressure, and the computer sees slip. The new valve rides on unworn sections of the bore, restoring the circuit without a reamer.
Start with a scan. TCC slip codes with clean solenoid circuits point to the regulator valve bore this kit fixes. A shift solenoid or pressure control solenoid circuit code is a different problem; check resistances at the case connector first, as covered in our 4L60E shift solenoid symptoms and testing guide. If you have no codes but the shifts are soft, flared or double-bumped, see the 4L60E common problems guide for how valve body calibration ties into 3-4 clutch failure. If the fluid is burnt, the frictions are already gone and the kit belongs inside a rebuild.
TransGo lists the SK 4L60E for 1993-2015 GM 4L60E, 4L65E and 4L70E transmissions, excluding hybrids. That covers the full-size trucks and SUVs from 1993 into the early 2010s, plus S10, Sonoma, Blazer, Camaro and Corvette applications. The kit includes TCC regulator valve components for vehicles with or without active fuel management, so identify which your engine has before installing. The 1982-1993 700R4 and non-electronic 4L60 use a different valve body and need the SK 700 kit instead. Not sure which you have? Send us your year and VIN or shop the 4L60E collection.
Plan for the valve body, pump and servo to be on the bench; the kit touches all three. Read TransGo's instructions through once before starting, keep each removed spring with its bore, and use the two included drill bits only where the instructions call for them. The kit also includes orifice cup plugs for the reverse input piston feed, so it fits best during an overhaul. A 4L60E rebuild kit with high energy clutches and band gives the new calibration fresh frictions, and a worn EPC solenoid will undo the pressure gains, so consider a new 4L60E pressure control solenoid on high-mileage units. Fill with Dexron VI, check the level hot, then reset adaptive learn with a scan tool. Our shift kit comparison explains how this kit differs from the Superior option.
| Fits | GM 4L60E, 1993-On |
| Type | Shift kit / valve body repair kit |
| Includes | Valves, shims, spacers, springs, instructions |
| Fixes | Soft and slipping shifts, weak TCC apply |
| Part number | TGOSK4L60E |
| Ships from | USA |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. The SK 4L60E is TransGo's standard recalibration kit for street and towing use. The HD2 Gear Command kit is a heavier-duty version aimed at higher-power or severe-duty builds. Both fit 1993-2015 4L60E family units.
No. Those hydraulically controlled units use a different valve body. Use the TransGo SK 700 kit for 1982-1993 700R4 and 4L60.
No. The same kit includes TCC regulator valve components for both AFM and non-AFM vehicles. Follow the instructions for your version.
Part of it is valve body work that can be reached with the pan off, but the kit also includes pump and reverse input piston changes. For the full benefit it should go in during a rebuild with the unit out.
Fresh clutches and a new 2-4 band if the old ones show wear, a new filter and pan gasket, and the EPC solenoid on high-mileage units. Refill with Dexron VI ATF.
