4L85E Solenoid Kit, new and ready to install. Fits the 4L85E. Ships fast from the USA.
If your Silverado HD, Sierra HD, Express or Savana with the 4L85E has started pulling away in second gear, refuses to upshift, or has set a P0753 or P0758 shift solenoid circuit code, this is the part most owners search for first. This 4L85E solenoid kit is the matched pair of on-off shift solenoids, A and B, that the control module fires to pick each of the four forward gears. They are listed against GM reference numbers 24230288 and 24230289 and they fit both the 4L85E and the lighter 4L80E, because the two transmissions share the same valve body layout and the same shift solenoids.
The 4L85E is the heavy-duty version of GM's big-case four-speed. Chevrolet Performance rates it at 650 lb-ft with ratios of 2.482, 1.482, 1.000 and 0.750. Two shift solenoids run the whole forward gear range. Solenoid A works the 1-2 shift valve and solenoid B works the 2-3 shift valve, and the module switches them in four combinations: A on and B off for 1st, both off for 2nd, A off and B on for 3rd, and both on for 4th. Each solenoid is fed battery voltage and switched on its ground side by the module. Neither one runs on full line pressure. They are fed actuator feed limit oil, which the AFL valve holds in roughly the 80 to 115 psi range. That detail matters when you diagnose, because a worn AFL bore starves good solenoids and makes them look bad.
Split the codes first. A circuit code means the module saw an open, short or driver fault, so it is a meter job: GEARS Magazine puts these solenoid circuits at 20 to 30 ohms, which works out to roughly 0.42 to 0.63 amps at 12.6 volts, with less than 0.10 volt drop on the ground side. Measure at the solenoid and again through the harness. A performance code means the electrical side checked out but the gear ratio did not match the command, and that can just as easily be a stuck shift valve or a burnt clutch. On level ground, compare input and output speed in the commanded gear. If 2nd reads close to 1.482, the clutches are holding and the solenoid or valve is the problem. Our 4L85E shift solenoid guide walks through the full chart and test order, and 4L85E valve body testing covers the AFL bore wear that causes repeat solenoid codes.
This kit is listed for the 4L85E and the 4L80E. The 4L85E went into 2004-2009 Chevrolet and GMC heavy-duty pickups and vans behind the 8.1L and 6.0L engines. It contains the two shift solenoids only. The EPC force motor and the converter clutch solenoid are separate parts. Before you order, compare the connector style and the part numbers on your old solenoids with the photo and the reference numbers above, or send us your year and VIN and we will check it. Everything else we carry for this unit is on the 4L85E parts page.
| Fits | 4L85E |
| Part type | Solenoid Kit |
| Condition | New |
| Brand | OEM |
| 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 the shift solenoid A and B pair only. The EPC force motor and the converter clutch solenoid are separate parts, so test those circuits on their own if your codes point there.
Yes, the kit is listed for both the 4L80E and the 4L85E. The two transmissions share the same valve body layout and the same two on-off shift solenoids.
Rarely. Both solenoids off equals 2nd gear, so a lost power feed, a bad ground, a damaged case connector or low AFL feed oil will cause it. Check voltage at the case connector before replacing parts.
Sometimes. P0751 is a performance code, meaning the gear ratio did not match the command. A stuck solenoid can cause it, but so can a stuck shift valve or a slipping clutch. Check the actual ratio in 2nd before you buy.
GM specifies DEXRON VI for the 4L85E. Top up to the correct hot level after the solenoid swap and recheck after the road test.
Clear the stored codes with a scan tool and road test through all four gears. Confirm each gear engages in the order the solenoid chart predicts before the truck goes back to towing.
