WOW! Rear Diff Fluid Change

[LanduytG]

After 1500 miles on my new Dmax I changed the rear diff fluid today. I have to say I have never seen such nasty looking fluid. It also had and over whelming amount of crap on the magnet.

I strongly urge those that have never changed the fluid to do so.

Greg

[Idle_Chatter]

There was a lot of silver metallic paste on the magnet in my diff when I first changed it too (at 1500 miles). I think there's an awful lot of "lap in" that occurs in the DMax diff. So, you have a new DMax? ;)

[Bill Knieper]

At 20,000 mine has developed a roar/whine sound above 50 MPH when some power is on it. When I take my foot off the accelerator the sound stops.
Thinking about changing the fluid. How many quarts does it take? Also, the plug on mine is not a magnet, so there is nothing on it.

[carco]

Changed mine @ 3000 miles after Fl. trip, little gray colored but almost no sediment no nasty crude. bob....

[jbplock]

Here is a snip from TxDoc's original Eaton Locker topic: Eaton's Recommendations on Locking Rear Diff Service (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=7;t=002814). ... Note the comment about carbon from the clutch surfaces...

"From Mr. Ralph Holmquist of Eaton, the maker of the locking differential: "The maintenance schedule for the rear axle was developed by American Axle & Manufacturing and GM truck based on multiple tests. The Eaton locker does not require additional maintenance nor does it add heat to the lube. The lube will darken due to the carbon wear on the clutch surfaces, much the same as a disc brake pad & rotor. This does not damage axle components such as seals or bearings. However, a new axle can produce excessive temperatures (plus 350 degrees F) due to the ring & pinion breaking in that will break the lube additives down. Avoid high loads, trailer towing and high speed extended driving during the initial break in of the vehicle. After the break in period axle temps will level at a much lower figure. Lube changes are a good idea because the additives are replenished and contaminates such as casting sand are eliminated. The axle is filled at the factory with a synthetic 75w90 GL5 rating made by Texaco under part # 2276. The GM service # is 12378261."

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[JimWilson]

Mine was swapped with Mobil 1 at the first oil change, which was 1K.

[RichC]

My fluid has been changed at regular intervals with either amsoil or mobil 1 synthetic. About 3 weeks ago, I started noticing a whine when coasting. Short of it is, I had to repalce the carrier bearings. There were chunks of bearing material out of the old bearing. Truck has 94,000 miles. No warranty on the bearings. Labor was $500 plus bearings. :mad: :confused:

[dmaxalliTech]

500 in labor to replace carrier bearings? WOW!

Average shop labor is about 70 per hour.. that would figure to roughly 7 hours of labor,, it dont pay that much to overhaul the entire axle...
Fair price for carrier bearings IMO is about 3 hours labor

[motovet]

Greg, mine loked like that too at about 1/K after my first tow. I changed it again at about 15/K and again at 40/K. Both times it was fairly nasty, but I can afford that insurance at your prices.

[northofthe52nd]

What is the fluid capacity of the locking rear differential on the '02 D/A 2500 HD? I can not find this info. anywhere in the operators manual.

[jbplock]

Originally posted by northofthe52nd:
What is the fluid capacity of the locking rear differential on the '02 D/A 2500 HD? I can not find this info. anywhere in the operators manual. Approx 4 quarts ...

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[northofthe52nd]

Thanks for the info. I did the rear and trans. fluid changes for the 1st time this weekend after 48k mi. I was amazed to see how clean and fresh the trans. fluid looked and the rear fluid was black, but no offensive odor. I tow a 31' 5er once or twice a year for a max. of 5k mi. each year. It took longer to change the fuel filter than to do both.

[ZL-1]

Changing my lube in my rear end was probably the easiest thing I have done to my truck. It took me a little while to locate the drain plug, not being able to see it laying on the ground. But using a 3/8th ratchet, the drain plug removal was very easy. Took out the refill plug, and using the little clear hose on the bottles, refilling the housing with 4 qts. of grape juice was almost as easy as starting up the diesel.Thanks for all the info.