I had a clunk that was emanating from the rear of my Dmax when backing out of driveway or parking stall. This went on for a few weeks as I attempted to locate where this was coming from. I got worried when it started to have a high pitched metal squeal that resembled a draging brake pad but much louder. I took it into dealer and they said they were "unable to duplicate complaint" yet they recommended differential service. The service was "topped off rear differential fluid to spec"<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" /><o:p></o:p>
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On the phone the service writer said it was about a quart low.... A Quart Low???? The truck has 7111 miles on it and is only 6 months old. There are no leaks or stains in my driveway so where the heck did a quart of fluid go? Is it possible that it left the factory low? This can't be normal and if it was THAT low for 7000 miles, can I get a warranty inspection on this BEFORE I begin pulling a 12,000 lb 5th wheel this summer?

Topping off does not constitute and inspection, does it?

Did the service writer state it was a qt low based on filling it to the bottom of the fill plug? GM is now stating that it can be 1.4 inches below the bottom of the fill plug. However, many of the members on this board do not agree. Here is a link to a thread containing the GM announcement.

http://dieselplace.com/forum/showthread.php?t=21902&highlight=fill+level+rear

For whatever it might be worth. Last week the pinion seal was replaced on the differential. The level was checked and topped off at the last oil change. 1500 miles latter almost half of the fluid had leaked out. Only saw a couple of small spots on the back. The dealer said that this was somewhat unusual.
I think they only filled it with gear lube, and forgot to add the additive for the limited slip clutches.