Finally, got the rear differential rebuilt today. New ring and pinion, bearings.
Still noisy though around 40 to 55mph. Way better than it was for sure. Maybe it will quiet down after it's ran a while?
Super nice guy. Showed me pictures of the pattern after it was done and from the pics it looked very good. (I was at work)
He went further and said since he could not fix the original complaint (noisy diff needs rebuilt) he would not charge me anything.
I told him he was the first honest shop i had been too in 2 years so I gave him $100 anyway as he did have time and effort into it.
He also said being an aluminum driveshaft the noise could be coming from the transmission 4L60E and the driveshaft could be magnifying the trans noise. He was not sure though but a possibility.
I have no idea if that can happen or not?
Anyway, it is definitely better now. It went from a very loud howl to a very tolerable low hum.
Next time i need a shop to work on my vehicle, thats where im going.
www.jpctrucks.com