Well, Ive tried to figure it out myself, but no luck. I have had a grinding noise coming from my jeep. It starts around 20ish mph and seems to get louder when under load. Ive read that it can be a u joint in the drive shaft, but they look to be in decent shape. Its hard to pinpoint exactly where its coming from but its irritating me not being able to figure it out. It has almost 200k miles on it and I don't know if the u joints have been replaced. Is it possible for them to look ok but be bad? Is there a way to test them to see if they are bad? It only makes the noise while driving. I can rev the engine with no noise. Also, it makes the grinding noise whether im in 2wd or 4wd. Any ideas?

 

dragging dums, axle bearings

 

Cool, I didn't even think of the axle bearings. I had figured it could possibly be wheel bearings or u joints because under load they have more pressure on them and would make sense for them to get louder. Axle bearings would make sense as well. Gonna put it on a lift and put it in drive to see if I can pinpoint where the noise is coming from.

 

Xfer case chain, with 200,000 miles, I would look at that