Took my new to me TJ into a good friend of mines shop last week to get a transfer case leak taken care of. I told them go ahead and sevice it so I know where I am at with that.Well they started changing all the fluids like I ask and found big trouble. Metal filings in the differentials so they pulled both covers and both ring and pinons are toast. I ask the guy I bought it from that installed the rear locker if the gears looked fine he said oh yea they were in great shape. Anyway now with the re-gear it did have 3.73 gears so that is what is going back in I am out over 4 grand to fix all the problems they found. Including the transfer case plus new oil pan gaskets and repair both diff's oh well. It's always the things uou can't see that get you know matter how the rest looks. Oh and we only put maybe 150 miles on it sice we bought it!!