Replaces both shift solenoids, the 3-2, EPC and TCC PWM solenoids plus the pressure switch manifold on 2003-up GM 4L60E and 4L65E units.
This kit is for the later GM 4L60E, the 2003-and-newer units found in Silverado, Sierra, Tahoe, Yukon, Suburban, Avalanche, Express and similar trucks, and it also covers the 4L65E and 4L70E that share the same valve body layout. It replaces six parts in one job: the A (1-2/3-4) and B (2-3) shift solenoids, the 3-2 downshift solenoid, the EPC pressure control solenoid, the TCC PWM lockup solenoid and the pressure switch manifold. Buyers usually land here with P0751 or P0756 shift codes, a P0748 pressure control code, lockup codes such as P0741 or P1870, a truck stuck in second, a harsh cold-start shift, or a flare on the 2-3.
The solenoids are the outputs and the pressure switch manifold is the input. The computer commands the A and B solenoids in the 4L60E pattern ATRA publishes in its GEARS solenoid chart (on/on for first, off/on for second, off/off for third, on/off for fourth), sets line pressure through the EPC solenoid, pulses the TCC PWM solenoid to apply the converter clutch, and fires the 3-2 solenoid to control downshift timing. Sonnax notes that all of these solenoids run on AFL oil that the AFL valve regulates to roughly 115 psi.
The pressure switch manifold is how the computer knows what you selected. Fluid from each manual valve circuit presses on small diaphragm switches in the manifold, and the switch combination tells the computer which range the shift lever is in. When a diaphragm leaks or a contact sticks, the computer can see the wrong range and respond with the wrong shift schedule or line pressure, or set range and pressure switch codes with nothing else wrong. Replacing the manifold with the solenoids removes one of the most common sources of confusing, intermittent shift complaints on these units.
Start with codes and freeze frame data, then look at wiring. Several circuit codes at once often mean a harness or connector fault rather than six bad parts. The solenoids can be checked for resistance at the case connector, but the pressure switch cannot. ATRA Technical Bulletin 269 explains that the computer sends 12 volts to each switch, so the switch must be tested with the engine running and everything connected, checking the voltage on each switch wire in every shift lever position. That bulletin also warns against prying the connector off or twisting it, which bends the pins. Our P0748 pressure control solenoid guide covers pressure complaints, and the 3-2 downshift solenoid guide explains flares on the 3-2 and 2-3.
Fits the GM 4L60E from 2003 up, plus the 4L65E and 4L70E that use the 2003-up valve body. The 2003-up EPC solenoid and pressure switch manifold differ from the 1993-2002 parts, so an earlier truck needs the earlier kit. Build dates around a changeover and individual applications can vary, so match the manifold shape and connector to your old parts or send us your year and VIN before you order. You can compare every year range on our 4L60E parts page.
If the internal harness is cracked or the connector is oil-soaked, add the 2003-2006 internal wiring harness. If a vacuum test shows worn bores, the remanufactured 2003-2008 valve body is the right next step, since new solenoids cannot seal a worn bore.
| Fits | GM 4L60E 2003-up; also 4L65E, 4L70E |
| Pieces | 6 |
| Includes | A and B shift, 3-2 downshift, EPC, TCC PWM solenoids; pressure switch manifold |
| Weight | 2.29 lb |
| Ships from | USA |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
Yes, for units that use the 2003-up valve body layout. Confirm by comparing the pressure switch manifold and connectors to your old parts before installing.
No. The EPC solenoid and pressure switch manifold changed for 2003. A 1993-2002 4L60E needs the earlier style kit.
It tells the computer which range the shift lever is in. A leaking or sticking manifold can cause wrong shift timing, wrong line pressure and range codes that look like solenoid trouble, so it is worth replacing during the same pan drop.
Not reliably. The computer powers each switch, so it is tested by checking voltage on each switch wire in every lever position with the engine running and all wiring connected.
Dexron VI. Refill and set the level with the transmission at operating temperature and the engine running.
A scan tool is needed to clear stored codes. After that, drive several full warm cycles so the computer can adapt shift pressures to the new EPC solenoid.
