rear end fluid change

[olimaxx]

hey guys i will be changing the rear diff fluid this weekend. i talked to the service writer at my dealer , he recomended to drop the cover and clean and inspect and change oil. he said to replace gasket and it would not void warranty. i bought a gasket at the parts dept. for 5 bucks. whats the torque specs and patern?

[DmaxMaverick]

With all your other mod's, I'm amazed your dealer would even mention warranty issues when servicing the rear end.

Removing the cover is not necessary. Just drain the lube out the drain and refill it. The bad stuff will come out with the waste and magnetic plug. Several folks have removed the cover and later decided it was just as well left alone. If you do remove it, I suggest not using a gasket. Sealer alone is a better choice, and won't leak or seep, like the gasket will in most cases. Get some of the sealer the dealer uses (not RTV), it is friendly with all the lubes you might use. RTV will break down with many synthetic lubes.

[Spartus]

BTW, the fluid in the rear axle is "lifetime" fluid, never needs replacing According to the engineers at AAM. It will turn odd colors, but thats due to the lithium grease used at assembly time.

[Turbo Al]

I did pull the cover on mine at the first oil drain and found that everything had come out of the rear end as far as oil and crud go so as DmaxMaverick said it is not really needed.
Oil change intervals are;
After first 500 Miles
After 500 miles of heavy towing
I WOULD SUGGEST every 30 to 40 thousand miles after that more if you tow big loads.
I do the same for the frount diff. except I change it after 500 miles of use (in 4x4) not at 500 miles.
Al

[JD Diesel]

Have 4000 miles on my truck now. Should i change my rear end oil now or wait until I get back from trip to washington. About 3000 mile trip ????? Plan on useing amsoil severe service 75 90. :D

[DmaxMaverick]

Originally posted by JD Diesel:
Have 4000 miles on my truck now. Should i change my rear end oil now or wait until I get back from trip to washington. About 3000 mile trip ????? Plan on useing amsoil severe service 75 90. :D If you haven't changed it yet, I suggest doing it before the trip. It should be well broke in with 4K on it. The lube you chose is a good one, IMO. I've been using Amsoil Series 2000 75-90 for about 80K. I'll be using the Severe Gear lube now, as it's replaced the Series 2000.

[JD Diesel]

Thanks Dmax I'm going to change it to day.

[JD Diesel]

Just drained my rear end and checked how much lube was in it. After I measured it there was 2 Q and 24oz. Owners manual says 0 to 1/2in from bottom of fill plug. After I put in what came out was about 1 1/2 from hole added 12oz more or 3Q. I'm going to think that is OK. Any other info I might need to know. Thanks :D :confused:

[madmatt]

spec is 3.1 qts or when checking no less then 1.4" below fill hole level or no more then 1" below the hole. GM changed the spec when it was determined that a diff full to the hole was more likley to spring leaks.

[JD Diesel]

Thanks maddmatt... :D With all my wisdom I made the right guess :eek: :rolleyes:

[ 06-16-2005, 07:21 PM: Message edited by: JD Diesel ]

[madmatt]

whats the :rolleyes: all about? you asked, I provided.

[JD Diesel]

:rolleyes: that was for me not you, sorry and thanks

[ 06-16-2005, 07:18 PM: Message edited by: JD Diesel ]

[jbplock]

Originally posted by madmatt:
spec is 3.1 qts or when checking no less then 1.4" below fill hole level or no more then 1" below the hole. GM changed the spec when it was determined that a diff full to the hole was more likley to spring leaks. madmatt,

Just curious ... does the spec change also apply to the 01-03's and is there a bulletin to reference? Both rear seals leaked (http://community.webshots.com/photo/65684589/139080723yFaWcq) on my 03 and were replaced under warranty ... the rear-diff has also been filled to the top of the fill hole since 5kmiles. I found the drivers side leaking at 24k and the passenger side at 40k - dealer covered the passenger side repair under warranty even though it was past 36Kmi http://forum.thedieselpage.com/ubb/icons/icon14.gif so I can't complain. But, I'm wondering if I should drop the level to prevent a future leak.. ?? When changing the fluid I used a little less than 4 quarts (spec was 3.8 quarts for the 03's when I looked it up)

smile.gif

[Steve Rapp]

I just changed my diff. oil in my 04 Duramax (9500 miles) yesterday based on what I read here on the color and the amount of crap stuck to the magnet. For reference, the drain plug is removed with a 3/8" ratchet and the fill plug is a 15mm six point socket as is the Allison's transmission drain plug. The oil was very dark and the magnet had some nasty black goop all over it. I put in all four qts of the very overpriced :eek: ($35.00 ea) GM "grapejuice" because I'm still within my 30,000 mile factory warrantee. The one thing I don't get is the front of the bottle said synthetic and the back said petroleum distillates :confused: I also bought a fuel filter from them also for $66.00 :mad: only to get home and compare it to a Wix I had bought from a parts store and they were identical in every way. What a rip off.

[JD Diesel]

WOW 35.00 A Quart give me a heart attack..... :eek: Amsoil severe service 75 90 is about 10.00 A Quart and is 100 percent syn.