4L70E Pressure Control Solenoid 2003-2008, remanufactured and ready to install. Fits the 4L70E. Ships fast from the USA.
Banging into Drive, soft slurred upshifts, or a pressure control code on a 2003-2008 Silverado 1500, Sierra 1500, Tahoe, Suburban, Avalanche, Yukon, Yukon XL or Escalade sends most owners looking for a pressure control solenoid. This listing goes a step further. It is a complete, remanufactured OEM GM valve body for the 2003-2008 4L60E, 4L65E and 4L70E, delivered with the late-style EPC pressure control solenoid, the shift solenoids and the TCC solenoid already installed. Each unit is cleaned, inspected and tested before it ships. The listing references interchange P74740-6 and GM-4643. If your old solenoid failed because its bore wore out, this replaces the bore along with the solenoid.
The 4L70E has no throttle cable, so the computer sets line pressure through this solenoid. It sends a variable current to the EPC solenoid, which feeds a signal to the boost valve and pressure regulator. The relationship runs backwards from what most people expect: ATRA's Gears Magazine documents roughly 0.9 to 1.1 amps commanded at idle for low pressure, falling toward zero at wide-open throttle for maximum pressure. Every clutch and the 2-4 band are applied from that one line pressure, so an EPC problem shows up in every shift.
GM changed the EPC solenoid partway through 4L60E-family production. Sonnax describes an early '92-'02 solenoid and a late '03-later solenoid with different pin and connector configurations, and sells a harness adapter because the two do not plug into each other's harness. This valve body carries the late style, so it matches the 2003-and-later internal harness. The listing itself warns that GM used several valve body designs over the years and that earlier and later assemblies should not be assumed interchangeable.
Put a pressure gauge on the line tap and watch commanded EPC current with a scan tool. If pressure does not follow the command, the cause can be the solenoid, a worn pressure regulator bore or a worn actuator feed limit valve. Our EPC solenoid symptoms guide shows how to read the amps, and the valve body testing guide covers the bore wear that makes a whole-assembly swap the better fix.
This assembly is listed for select 2003-2008 GM trucks and SUVs with the 4L60E, 4L65E or 4L70E. On the 4L70E, that is the 2006-2008 portion of the run. Before ordering, compare your valve body casting, EPC solenoid style and harness connectors with the photos, or send us your year and VIN and we will check it. The 4L60E, 4L65E and 4L70E interchange guide explains what crosses over between the three. The full lineup is in the 4L70E parts collection, and if you only need the solenoid, the single late-style EPC solenoid is listed separately.
If the internal wiring is brittle or chafed, pair this with a new internal wiring harness so the new solenoids are not fed through an old connector.
| Fits | 4L70E 2003-2008 |
| Part type | Pressure Control Solenoid |
| Condition | Remanufactured |
| 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.
No. It is a complete remanufactured OEM GM valve body with the EPC pressure control solenoid, shift solenoids and TCC solenoid installed, as shown in the photos.
No. Sonnax notes the early '92-'02 and late '03-later EPC solenoids use different pin and connector setups. This assembly carries the late style for 2003-2008 harnesses.
The listing covers select 2003-2008 4L60E, 4L65E and 4L70E applications. Compare the casting and connectors with your old valve body or send us your year and VIN.
Harsh engagement, soft or flaring shifts, codes such as P0748 or P0960, and in time burnt clutches from low line pressure. A pressure gauge confirms it.
Clear the transmission adaptive values with a scan tool, then drive with a variety of light and moderate throttle upshifts so the computer can relearn shift timing.
