Hey guys my truck is making a vibrating noise from the back, now I just got the diff fixed but now it's making a vibrating sound when I let it coast.
When I accelerate it sounds normal but at certain speeds it reaches like 40km/h, and 80km/h when coasting it makes that noise and once I accelerate or brake the noise stops.

Any ideas what it is???
Thanks

 

How long has it been since the rear end rebuild? sounds like they did not set up the pinion depth correcctly. How is your backlash at the pinion yoke, you can put the truck in nuetral, chock the wheels and move you pinion yoke back and forth to see if you have a lot of backlash I am not 100% sure on the specs but somewhere between 8 and 12 thousandths should be OK

 

sounds like the rear end whining to me also from then gears not being said correctly.

 

Yep....backlash or somethings not set up right.
Take it back imedialtey for them to fix it mate!.

Al.

 

Alright thanks for the input guys...the diff got fixed about 3-4 weeks ago so yeah like you guys said it could be that

 

it could be all of thoose things.but it also could be a u-joint going out also.my rear end was doing the samething as you described and it turned out to be a u-joint