Hows it going fellas. The time has come for me to change the rear diff fluid in my truck. Im here to ask you all what you think is sutiable to run.

I have 60k miles on it and I know I can start running Synthetics now. Just don't know which brand to use.

Also I was thinking, why i'm in the need to change it would putting a Mag Hytech pan on the rear diff make any difference? I know it would hold more fluid so that would make it a little cooler correct?

One more question, while im under there I may as well change the transfer case fluid, any good suggestions on that?

*edit* Once the seal is broken on the rear diff, would I need to replace it w/ a new seal?

Thanks, Nathan

 

Have you considered Royal Purple 75W90 or Redline? Both high quality synthetics and run about $10 qt.

The gasket is re-usable. If you're hauling and towing often, the larger diff cover will be beneficial, if not then I wouldn't bother, unless ofcourse you want it for the bling-factor which is okay with me.

 

Where does one purchase the Royal Purple 75w90? Also im sure this is in my owners manual, but how much should I put in? Asking here is easier then reading the book trying to find it.

I won't lie, I want the larger diff cover for the looks. It's not a nescessity but it'd be cool to have.

 

Nathan,

Is this the first time to change the fluid? 60,000 miles? Wow, I bet that stock fluid is dirty. Mine was dirty at 15,000. I added a Mag Hytec rear diff cover on mine then and I just changed it again couple of weeks ago at 30,000.

The MH does make changing it easier (drain plug) and supposedly helps the fluid run cooler. I figured it couldn't hurt to have it, but admittingly....the biggest reason for me is the "bling". I have a pic of it in my gallery.

Also, I happen to run Mobil 1 75/90 fluid in my front and rear. I get it at Auto Zone and seems to be working great. BTW, if you decide to go with Royal Purple, I have seen it at NAPA. There are several good brands out there. And, honestly I have never heard of any of them not doing the job.

You asked about the transfer case.......and I will just tell you that I change all of those fluids out every 15k. Front and Rear diffs (mobil 1)....Auto Tranny fluid/filter....and transfer case (ATF +4).

 

It came with synthetic from the factory.

 

EEK! First change at 60K...

Any good quality synthetic will work, Mobil 1, Valvoline, Royal Purple, Redline, Amsoil...



Transfer Case (up to 5pts/3qts) ATF+4

Frt & Rear Axle (up to 5 pts frt & 8pts rear/8 qts)
GL-5 SAE 75W-90 Synthetic. NO ADDITIVE

 

Twiz the night before Christmas and all through the house was no sound but the flipping of the pages of a owners manual.

 

No No, this won't be the first time the fluid is getting changed. I purchased the truck used and in the glove box were some receipts from the previous owner. The fluids were changed at Jiffy Lube at 30k miles. I don't know if it was done before that though, hopefully it was.

Thanks for all the helpfull answers guys, I appreciate it.


TexasCTD- Where did you purchase your MH cover at? I figure I need some bling under my truck since i'll be lifting it here shortly.

 

Changing my front and rear differential fluids this weekend. FYI - the rear diff (AAM 11.5) takes 3.6 Litres (3.80 Quarts), and the front (AAM 9.25) takes 2.2 Liters (2.32 Quarts). Reference:Link

Questions: Do both axles have an O-Rings for the differential cover gaskets, i.e. are they both re-useable? Or, are they just a re-useable material?

Also need to change the T-Case fluid, book says to use ATF+4 but does not specify volume of oil to use, anyone know how many quarts I will need?

Thanks, didn't mean to hijack the thread!

 

http://www.genosgarage.com/CoastalDa...D=1616&CATID=1

Nathan...you can get the MH from Genos Garage. Link posted above.

Eastment....not sure exactly how much ATF +4 you will need on the TF case. I just drain it from the bottom hole, and refill till it comes out the top hole. Then wipe it clean.

 

Right,... just want to know approximately how many quarts to purchase for the job. I figure approximatley 4 will do?

 

Eastment,

It took approximately 3 quarts of ATF +4 on the transfer case.

I used 9 quarts for the tranny refill with a Mag Hytec DD tranny pan. Normal is 5 quarts for tranny, because the MH holds 4 quarts above stock.

I just buy it by the gallon jug from the dealer and usually have some left over. Not a problem, because 15,000 miles from now, it will get used up then.
Hope that helps.

 

It does, thank you!