Refurbished shift, EPC, TCC and 3-2 solenoids on an internal harness with pressure switch, filter and pan gasket for 2003-2005 GM 4L60E and 4L65E.
A 2003-2005 Silverado, Sierra, Tahoe, Suburban, Yukon or Avalanche that suddenly holds one gear, bangs into drive, or flashes the check engine light with a pile of transmission codes often has an electrical problem inside the pan rather than a mechanical one. This kit is a budget-friendly way to swap the whole valve body electrical package at once. It uses refurbished solenoids mounted to an internal wiring harness with its case connector, and adds the pressure switch manifold, a pan filter and a cork pan gasket, so one pan drop handles the entire job on a 2003-2005 4L60E or 4L65E.
Gear selection in the 4L60E comes from just two on/off solenoids, A (1-2) and B (2-3), switched in combinations by the computer. The other solenoids tune how each event feels. The EPC solenoid raises and lowers line pressure, the TCC lock-up solenoid opens the converter clutch passage, the TCC PWM solenoid ramps that apply in, and the 3-2 solenoid manages clutch overlap on downshifts. The pressure switch manifold is the sensor half of the package: it reports which range the manual valve is in, so a leaking manifold can make the computer think the truck is in the wrong gear range. On 2003-2005 trucks all of these plug into a harness that is unique to those years.
Scan for codes and note whether they are circuit codes (an electrical fault) or performance codes (the computer saw the wrong ratio). Circuit codes on several solenoids at once almost always trace to the harness or its connector; ATRA found that one bad crimp on a shared feed circuit could set P0740, P0753, P0758, P0785 and P1860 on 4L60E units. Unplug the case connector and measure each solenoid circuit with an ohmmeter. If the electrical tests pass but the shift is still wrong, the problem may be valve body bore wear, which Sonnax says is common in this family and confirms with a vacuum test. Our P0753 and P0758 shift solenoid guide and the 4L60E common problems guide help you rule out the mechanical causes first.
This kit is for GM 4L60E and 4L65E transmissions built for the 2003, 2004 and 2005 model years only. The harness and connectors changed for 2006, and the 1993-2002 version is different again, even though several solenoid part numbers carry across. Check the part numbers on your old components against the OE numbers listed for this kit (10478112, 10478120, 10478131, 24230298, 24215111, 24219581, 24220158, 24203101, 8677314 and 24212327 among them), or send us the year and VIN before ordering. Other year-specific parts are on our 4L60E transmission parts page.
Because these solenoids are refurbished, this kit suits a daily driver that needs a reliable electrical refresh without new-part cost. If you only need the lockup side, the GM 24227792 TCC PWM solenoid is sold on its own, and the aluminum deep pan adds fluid capacity for trucks that tow.
| Transmission | GM 4L60E, 4L65E |
| Years | 2003-2005 only (not 1993-2002 or 2006-2007) |
| Includes | Shift A/B, 3-2, EPC, TCC solenoids, internal harness, pressure switch manifold, filter, pan gasket |
| Condition | Refurbished solenoids |
| Replaces | 10478112, 10478120, 10478131, 24230298, 24215111, 24219581, 24220158, 24203101, 8677314, 24212327 |
| Shipping weight | 2 lb |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
The solenoids in this kit are refurbished. That keeps the price down while still renewing the harness, pressure switch manifold, filter and pan gasket. If you want all-new solenoids, look at the other 2003-2005 kits on our 4L60E page.
No. The 2003-2005 harness and connectors differ from the 2006-2007 and the 1993-2002 versions. Use the kit that matches your model year, and send us your VIN if you are unsure.
The pressure switch manifold tells the computer which range the transmission is in. A leaking or failed switch can cause wrong-gear shifts and codes that look like solenoid faults, so it makes sense to replace it while the pan is off.
Yes, ideally. Clear the codes and perform the transmission adaptive relearn so the computer resets its shift pressure tables. Without it, shifts can stay harsh or erratic until the adaptives slowly relearn.
A pan and filter change usually takes about five to six quarts of Dexron VI on a standard pan. Add slowly and check the level hot in park, since overfilling causes foaming.
