Driveline Screech ???
 

63 Chev k10 454,400Turbo,12-bolt 3.73 posi

I am in the "sorting out" stage of a 2 year project. On my first trips around the block, I have 2 driveline noises.
1. a "screech" that takes place under acceleration and at times when I start it up cold and in park. (but will go away when I "goose it" in park, but comes back as soon as I drive up a grade or accelerate hard.)
2. a "whine" that takes place under load whether it be acceleration or deceleration and is constant almost from start to stop. (but will stop when I let off the accelerator and put in neutral)

I have personally rebuilt the rear, and double checked the gear pattern, it is right on.
This week I rebuilt the transfer case with all new bearings, bushings and have correct tolerances and end play.
I pulled the trans today, the flexplate has no cracks, my drain pan has clean fluid, and so far have disassembled the front pump and forward clutch assy and everything is sanitary/new.
The driveshafts have new u-joints and have been balanced.

Could I have a bad rear main/thrust bearing? I checked end play with an indicator and the crank moves back and forth about .010.
Could the torque convertor be bad?
Any ideas?

I am about ready to start a very large bonfire...

Geez, That's a tough one.
I assume you replaced the carrier bearing in the driveshaft, If it even has one. (Hmm, Transfer case, probably one piece driveshaft)

The only other thing I can think of is somehow you are stuck in 4wd.

My ony suggestion is to jack up the rear wheels and have someone ride the brakes to try and duplicate the noise so you can figure out where it is comming from.

Good Luck

this may sound dumb but how are the alt/accessry belts on the engine?

Thanks for the suggestions. I thought it was the transfer case also but pulled it. Transfer case is good, shifts in and out like it should, gears are in good shape, just last week while apart replaced the front output shaft, constant mesh gear, idler shaft, bronze bearing on the rear output shaft and all bearings. Noise still existed. I think I can eliminate the t-case.

Not an accessory or belt noise, I've run it with out the belts.

Since the trans is out, I'm going to run the engine tonight to see if I can eliminate timing cover rub or rear main thrust bearing.