Full solenoid set for the GM 4L60E valve body: EPC, TCC, PWM and 3-2 control, covering 1993-2006 Chevy, GMC, Pontiac and Cadillac units.
If your Chevy, GMC, Pontiac or Cadillac with a 4L60E is setting P0748 or P1860, shuddering at 45 mph, refusing to lock the converter on the highway, or banging into second with line pressure stuck high, the fault is usually in the four solenoids that regulate pressure and converter apply rather than in the clutches. This kit replaces exactly those four: the EPC (pressure control) solenoid, the TCC lockup solenoid, the TCC PWM solenoid and the 3-2 control solenoid. It is the pressure-and-lockup half of the valve body's electrical system, and it is listed for 1993-2006 4L60E, 4L65E and 4L70E units.
The 4L60E picks its gears with just two on/off shift solenoids, A and B. Everything about how a shift feels and whether the converter locks is handled by the four parts in this box. The EPC solenoid is a variable force motor: the computer changes the current through it to raise or lower line pressure, so a worn EPC either lets pressure run to maximum (harsh, firm shifts) or lets it sag (soft, slipping shifts). The TCC solenoid opens the circuit that feeds converter apply, and the PWM solenoid modulates that apply so lockup comes in smoothly instead of with a thump. The 3-2 control solenoid times the release and re-apply of the 2-4 band and 3-4 clutch during part-throttle and kickdown downshifts. All four are fed by the AFL circuit, which Sonnax describes as regulated to roughly 115 psi in this transmission, so a leaking O-ring on any one of them bleeds pressure from the others.
Note what is not in this kit: shift solenoids A and B. If your codes are P0753 or P0758, or the truck is stuck in one gear, you want the 4L60E shift solenoid A and B kit instead of, or along with, this set.
Measure at the case connector before dropping the pan. ATRA Technical Bulletin 269 gives 3.5 to 8.0 ohms for the pressure control solenoid and 20 to 40 ohms for the shift solenoids; a reading far outside range points to the solenoid or the internal harness. ATRA bulletin 583 also documents a bad crimp on the shared 12-volt feed circuit setting several solenoid codes at once, so check the connector and pins if multiple codes appear together. Our P0748 pressure control solenoid guide walks through the EPC test, and the TCC solenoid and P0740 guide covers lockup faults. If a P0741 slip code persists with good electrical readings, suspect valve body bore wear, which no solenoid will fix.
The listing covers 1993-2006 4L60E, 4L65E and 4L70E transmissions and crosses to OE numbers 24212327, 10478120, 24227747 and 12121299. The vehicle list centers on 1993-2002 applications: Blazer and Jimmy, Envoy and Trailblazer, Tahoe and Yukon with 4.8, 5.0, 5.3 and 5.7 liter engines, 1994-2002 Camaro and Firebird, the 1994-1996 5.7 liter wagon and the 1993-1996 Fleetwood. Valve bodies changed in 2003, and connectors and solenoid styles differ between early and late units, so compare the numbers on your old solenoids with the OE numbers above, or send us your year and VIN and we will check it. Browse every option on our 4L60E parts page.
Most trucks do this job without removing the transmission. Drain and drop the pan, pull the filter, unplug each solenoid from the internal harness and remove its retainer or bolts. The EPC and PWM solenoids are bolted to the valve body; if you lower the valve body for access, watch for the checkballs in the spacer plate, keep the bolts in order since lengths differ, and torque them evenly so the plate does not warp. Lube every new O-ring with ATF, refill with Dexron VI, clear codes and let the computer relearn its shift adapts over a few drive cycles. Reuse of an old filter is a false economy here; the 4L60E pan, filter and gasket kit closes the job up with fresh parts.
| Fits | |
| Solenoids included | |
| Replaces OE | |
| Shipping weight | |
| Box dimensions |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
No. It contains the EPC pressure control, TCC lockup, TCC PWM and 3-2 control solenoids. Shift solenoids A and B, which set P0753 and P0758 and decide which gear you are in, are sold separately as an A and B kit.
Possibly, but check first. The listed vehicles are mostly 1993-2002, and GM changed the valve body for 2003. Compare the part numbers on your old solenoids with 24212327, 10478120, 24227747 and 12121299, or send us your year and VIN.
If the shudder comes from erratic converter apply, a new TCC and PWM solenoid often cures it, especially with a P1860 or P0740 code. Change the fluid at the same time. If the converter clutch itself is worn or the valve body bores leak, solenoids alone will not stop it.
Dexron VI automatic transmission fluid. It is backward compatible with the Dexron III specified for older 4L60E units.
Clear the stored codes and, if your scan tool offers it, reset the transmission adaptive values. Otherwise the computer relearns shift pressure over several normal drive cycles, so the first few shifts may feel firmer than usual.
