OEM 24210865 4L80E B Shift Solenoid: Symptoms, Specs & Install

If you searched for 24210865, this is the part. 4L80E B Shift Solenoid for the 4L80E. Below: what fails, what the symptoms look like, resistance specs to test before replacing, and the step-by-step install procedure.

What it does

Pairs with the A-solenoid to schedule shifts. Failure typically prevents overdrive engagement.

Fitment

1991-2013 GM heavy-duty trucks (Silverado 2500/3500, Suburban 2500, Express vans, motor homes).

Common failure symptoms

P0752, no 3-4 overdrive shift, stuck in third, transmission runs hot in OD-locked mode

Electrical specs

Run a resistance check before condemning the solenoid. Bad wiring, corroded harness pins, or a failing PCM driver can cause the same symptoms as a bad solenoid. Eliminate cheap causes first.

Replacement procedure

1. Drop pan and filter
2. B-solenoid sits next to the A on the valve body
3. Disconnect harness clip
4. Remove 10mm mounting bolt
5. Pull straight out
6. Lubricate O-ring with fresh ATF
7. Torque mounting bolt to 10 ft-lbs
8. ALWAYS replace both A and B together if one fails — they age at the same rate

Estimated time: 1 hour for someone who has done this before, 2-3 hours for first-timers. Tools needed: 8mm and 10mm sockets, snap-ring pliers (if removing the valve body), torque wrench, drain pan, fresh ATF.

Related diagnostics on Gearbox Insider

4L80E rebuild parts guide • Shop by transmission symptom • Solenoid testing without a factory scan tool