What's that loud SQUEAK?!

Maintenance/Repairs
1

I’ve got a 2005 Avalanche (basically, a Silverado) which has suddenly developed a possible illness. Whenever I start the truck and begin moving (forward or reverse), I hear one (and only one) loud squeak that seems to be coming from the general area of the torque converter or drive shaft (but who knows exactly). The squeak doesn’t happen immediately upon moving but always happens within the first 20-30 feet of movement and then no more. If I put the truck in park, re-engage the automatic transmission and start moving, I cannot recreate the sound. However, if I turn off the engine altogether, restart the truck and begin moving, it happens again exactly as before. It happens every time the vehicle has been restarted, regardless of whether the engine is hot or cold. Once it’s happened, I can drive hundreds of miles and it won’t happen again until I turn off the engine and restart it. Further, I’ve determined recently that if I start the truck on a hill and let it roll while in neutral and without a foot on the brake, the squeak still happens. Therefore, it’s not dependent upon the transmission being in gear or the brakes being applied!

Any thoughts? HELP!!!

2
I've determined recently that if I start the truck on a hill and let it roll while in neutral and without a foot on the brake, the squeak still happens.

Repeat this by stopping on the hill, put into neutral, turn the engine off, then coasting without starting the engine (remember, you’ll have no power steering and run out of power brakes after a few applications).

3

Sounds like brakes sticking.

4

Have someone stand beside the truck squatting down when you first move the truck to pinpoint the location. If it is near the rear of the transmission, it could be a dry transmission tailshaft seal making a little noise first thing in the morning.

Is this Av 4WD? Possibly an issue with the transfer case?

5

I had a rear u-joint go dry on my truck one time, and it had a similar squeak symptom. But it had nothing to do with re-starting the engine… Just that if the drive shaft had been rotating and warmed up, it would stop squeaking. I fixed it by lubing all the u-joints.

6

I like @GeorgeSanJose 's thought there. Dry U-joint. Yeah.