My rear end was close to biting the dust when I took the truck in the other day. Haven't gotten the entire story on what the problem was, but there was enough play in the rear diff for the ring gear to score...no, grind the hell out of the differential cover. Luckily I'll be getting my money's worth out of the powertrain warranty I purchased with the truck when I bought it used.

Is there any common problem that could cause a failure like this? I recently towed a $10k lb trailer cross country, then proceeded to play in the sand for a day. Luckily I took it in before it totally gave out.

Also, they are replacing the rear with a used one (terms of the warrantly ). Should I have any worry about problems in the future?