I got the oil changed in my truck the other day in preparation for a road trip (ended up taking different vehicle - w00t!). I asked the gents doing the oil change to check the fluids on the diffs, transfer case, etc. All were pretty much fine with the exception of the front. The guy called me out of the waiting area and had the oil on his hand and it was grey in color. I grabbed a white paper towel and asked him to check it again (he had cleaned his hand) and wipe his hand on the towel. I stepped out into the sun with it and looked at it and there were no shimmers or the likes that would make me think it was metal, but I cant think of any other reason it'd be like that. The rear wasn't like that and was much clearer.

The truck has less than 25k miles on it and the diff fluids have never been changed. It's been out on trails but nothing major, to the beach a few times, etc. Axles have never been submerged (at least that I recall in the 2+ years I've owned it).

Although I'm not a newb to vehicle maintenance, I /am/ a little timid about changing the diff oil on this truck myself. My concern is that somehow my front end roasted - although I dont feel anything while driving it. I'm also concerned that if I take it to the dealer that I'm going to get the typical run around that it's "general wear and tear" and that it wont be warrantied if there's something genuinely wrong. Not to mention the service bill just to have them look - ugh.

Any chance I'm being overly worried here? I've read through threads that say to use a different oil for the front versus the rear. Is this possibly the case and I've nothing to fret?

 

If it is in fact grey in color it needs to be changed.. could of got some water in it.. it is a very easy job to DIYS or maybe an hour labor max for a shop to do it for you.