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It about the front lockers. I know there’s a lot of problems with vacuum lines and wheel bearings on these. I even found a dry wheel bearings on this one but here is the deal. The front locker vacuum solenoid is not being controlled. We can by pass the vacuum and the grinding is a lot better. I can control it with a test like it is just not getting the ground signal. Dose anyone know what’s supposed to control it and where I should start
Well guys the TCCM controls the ground that goes the the solenoid. I do not have the ability to program the TCCM. I did show the customer he could bypass the solenoid on the vacuum and it would unlock his hubs. But I had to have him take it to the dealership I HATE that!
FWIW, I rarely find issue with the TCCM on these trucks. More often, I find the one-way check valve in the vacuum line going to the vacuum reservoir to be leaking intermittently. That results in low vacuum to the hubs after a long enough cruise at part throttle.
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