Sometimes when I turn I hear a noise that I can only describe as a marble or rock rolling on a truck bed. I have a 4runner so that is not possible. I recently had some differential service done so im wondering i they messed that up and the noise is a result of it.

 

i had a VERY slow leak on the driver side axle seal, it drained the gear oil out a bit over time, also cause the wheel bearing to fail. i spent 3 days just to found out where the noise was coming from the rear wheel.

ask a frind to rock the vehicle while you get under see if you can find the problem.

 

Will try this, thanks, it sounds like it is coming from the rear though.