- Dec 6, 2011
- 782
Okay, I am stuck here. Replaced most common failure items, but still get a C0374 code. All is good in 2WD. If I switch to 4WD Auto, when I corner next, "Service 4WD" lights with code C0374. If I turn sharply, it starts crazy crowhopping as if it was in 4WD and not A4WD. It then stays stuck in A4WD until I stop and restart and the service light goes away, until the very next corner. To get back to 2WD, I have to stop, shut down, restart and shift immediately. I don't even know if it is actually in 4WD or not.
2004 Trailblazer, so TCCM should be fine. (Pulled fuse #8 anyway just for fun.) Transfer case fluid was replaced 20,000 KM ago.
4WD switch was replaced last year when it began to get a bit lazy switching to A4WD. I just replaced the transfer case encoder motor and the 4WD actuator. No change. (I used Genuine GM parts for all.)
When I was replacing the actuator, I tested the shift fork and it seemed to move so it was not broken completely. I rattled the front passenger driveshaft at the disconnect, and there is about 1 to 2mm play; enough to cause a clacking sound when I shake it.
I read the TSB on the C0374 but haven't had a chance to get back under and check the wiring. I am now confronted by two alternatives:
- pick up a transfer case speed sensor and a new harness connector, or;
- just pick up a new 4WD disconnect, and use my new GM actuator instead of the cheap junk actuator these Chinese parts usually come with.
Has anyone solved a C0374 code with a new disconnect?
Do the bearings in the disconnect sound really bad or is a bit of play and some clacking noise when you shake the driveshaft normal?
2004 Trailblazer, so TCCM should be fine. (Pulled fuse #8 anyway just for fun.) Transfer case fluid was replaced 20,000 KM ago.
4WD switch was replaced last year when it began to get a bit lazy switching to A4WD. I just replaced the transfer case encoder motor and the 4WD actuator. No change. (I used Genuine GM parts for all.)
When I was replacing the actuator, I tested the shift fork and it seemed to move so it was not broken completely. I rattled the front passenger driveshaft at the disconnect, and there is about 1 to 2mm play; enough to cause a clacking sound when I shake it.
I read the TSB on the C0374 but haven't had a chance to get back under and check the wiring. I am now confronted by two alternatives:
- pick up a transfer case speed sensor and a new harness connector, or;
- just pick up a new 4WD disconnect, and use my new GM actuator instead of the cheap junk actuator these Chinese parts usually come with.
Has anyone solved a C0374 code with a new disconnect?
Do the bearings in the disconnect sound really bad or is a bit of play and some clacking noise when you shake the driveshaft normal?
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