I have a 1999 V6 4x4 Tacoma. The rear end has began to make a grinding noise. It first began only when in 5th gear. If you would let off the gas, the noise would go away... If I gave the truck a lot of gas it would go away... It would only make the noise when the gas pedal was slightly pushed in. After a couple of days, the truck started vibrating after about 30 mph???? Any ideas..????

 

Possibly a bad ring and pinion.

 

or u-joints- axle bearings

 

The garage said it was a bad pinion bearing, along with a bad rear u-joint. Sound pretty feasable?