I have a 1993 Manual transmission toyota pickup (rwd). The other night I heard grinding that sounded like it was coming from directly beneath me when I was accelerating at high speeds. The noise isn't there when I'm cruising, only when I accelerate. I had a shop change my diff fluid and transmission fluid a few weeks ago, and I'm hoping that the rumors of changing your manual transmission fluid aren't true. Any tips as to what the noise may be? I looked in my haynes book and it sounds like it could be u-joint issues. I dunno.

 

You got 2 piece driveshaft?? Check universals, carrier bearing and maybe loose pinion yoke.

 

Thanks! I'll check those out!

 

I have an 89 pickup with the 3.0 v6 in it. Ive been having a similar noise. In my case, when I am in third gear and I get to about 40 mph, I can hear a grinding noise when I am on the gas but once I let off the gas the noise goes away. the noise goes away when I pass 50mph, but still only when I am on the gas. This noise is never present when I am not giving it gas. Also when I am on the highway in 5th gear going about 75+, if i let off the gas slowly, I can gear that noise but way louder. Kind of sounds like a sharp object scratching a spinning disc. Along with all that, I can feel my truck jerk to the side when I give it gas and when I let off the gas it jerks back to place. I recently lowered my truck with blocks in the back and loosened the torsion bars in the front, dont know if that would cause anything. If you found the solution to your problem could you please lmk.