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2003 chevy trailblazer_lt_ext
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Discussion Starter · #1 · (Edited)
I went to the Dealership this morning and they sold me this oil for the rear differential ( I have a G80 locker) Is this correct because everyone is saying it costs $32.00 a liter/Quart. This works out to $12.00 lt/Quart

AC Delco # 89021672 Sae 80W-90 (Exceeds GL-4 requirements)




In the manual oils have changed over the years Dex III to VI so I'm not sure.

Thanks.
 

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2004 gmc
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That's good stuff for the rear diff. Mobil1 also makes one that meets spec. Don't buy it from the dealer unless you need to keep them in business for some reason, like you're dating the owner's daughter. :woot:

If you're doing the rear, it's also time to do the front. Don't forget it. Why would you do one and not the other? Read and obey the Owner's Manual maintenance interval chart.

And it's also time, perhaps overdue, to change the fluid in the transfer case. That's GM Autotrak II fluid - ONLY available from the dealer. 2 quarts needed - for some dumb reason this isn't in the manual.

Dexron is ATF. Not an oil. Please read the manual more carefully. Please never confuse the two, or else you'll be posting a very sad message here when you break some expensive bit of the vehicle.
 

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2003 chevy trailblazer_lt_ext
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Discussion Starter · #3 ·
Thanks Roadie. I did the front diff yesterday, with Lucas Syn 75W-90, I doing the transfer case now with Autotrac II( need a break from the hand pump) and later today drop the tranny pan, change filter and instal drain plug. I will get to the rear diff later today or tomorrow.

About the Dex III, I was speaking about the change from III but now it ok to use VI for the Tranny.

It was $12.00 a litre, others were saying it $32.00 a liter, that's why I was unsure.
 

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2008 gmc envoy_sle
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I went to the Dealership this morning and they sold me this oil for the rear differential ( I have a G80 locker) Is this correct because everyone is saying it costs $32.00 a liter/Quart. This works out to $12.00 lt/Quart

AC Delco # 89021672 Sae 80W-90 (Exceeds GL-4 requirements)




In the manual oils have changed over the years Dex III to VI so I'm not sure.

Thanks.
I'm new here (first post) but have basically the same question. I thought the G80 (locker) required a synthetic 75W90 GL-5 lube! I am looking for an alternative to the GM stuff (#12378261) which is expensive.
 

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2002 gmc envoy_slt
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Personally, I like Royal Purple's gear lube. Their stuff meets GM's spec, has all the modifiers needed for LSDs and seems to prevent and actually stop the light seepage that seems common on our differentials. - I've been under several TB/Envoys and they ALL seemed to have that moist look from very light seepage. Change the fluid with RP and the seepage stops and the area dries up.

Don't forget the transfer case, if its axle lube time, it most likely is time to change out the transfer case oil as well. To my knowledge there are only three lubes that meet the Auto-Trac/II spec, the first is the GM stuff, Amsoil makes one and RP's Synchro-Max. (I filled with Synchro-max at the same time as I changed the axle fluid, so issues at al).
 

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I thought the G80 (locker) required a synthetic 75W90 GL-5 lube!
Mobil1 makes a synthetic "LS 75W90" that meets all the specs and added the limited slip additive required by true limited slip diffs. The factory manual doesn't mention any need for LS additives, and I personally haven't used them. I just put in the Mobil1 75W90. Available everywhere.

But a few members reported noises coming from the rear diff that they attributed to the G80, and when they added a little bottle of LS additive, the noises went away. So the rumor (here at least) got started that the G80 requires LS additive and my information doesn't confirm that.

The transfer case fluid used to be ATF in older vehicles, but with the much more active clutch assembly in newer designs, they needed a similar LS additive to reduce clutch chatter. That's the reason behind the AutoTracII fluid.

And this final reminder isn't aimed at you specifically, but the hordes of lurkers: The Owner's Manual recommends transfer case fluid changes every 50K miles! Ignore this at your peril. It's amazing the number of folks who come in here with 4WD problems at 100K+ miles who have NEVER changed the fluid.
 

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2008 gmc envoy_sle
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And this final reminder isn't aimed at you specifically, but the hordes of lurkers: The Owner's Manual recommends transfer case fluid changes every 50K miles! Ignore this at your peril. It's amazing the number of folks who come in here with 4WD problems at 100K+ miles who have NEVER changed the fluid.
:thumbsup:My Envoy has about 5,000m now and I just towed my 5400lb boat to Pittsburgh. The truck manual states to change rear diff fluid after the first 500m tow(due to heat) so I figured it wouldn't hurt for the Envoy either. I just thought I could use something other than the Grape juice (GM stuff) all the Mobil1 stuff I found is the LS version. I bought 2qts of LS 75W140 for the G80 on my 2500HD (all they had) and 3qts of LS 75W90 for the Envoy and to finish off the truck. Do the front diffs need the LS version or not?

I think I may just bite the bullet and buy the Gm stuff for the rears. I want to make sure it gets the right stuff. And trying to find an answer on the internet has been difficult, some say you need it others say no. The manual doesn't say to add any. Some people think that's because it's already built in to the fluid ( who knows for sure though)

Thanks
 

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Our front diff is open (no locker or LS). I've never read that the LS additive will harm anything in a non-LS diff. I would have no hesitation using the LS Mobil1 in either front or rear diff.
 

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2006 chevy trailblazer_ls
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So will the LS additive offer more protection? Is the LS additive stopping the seal leakage that YLAB mentioned with the Royal purple?
 

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2002 gmc envoy_sle
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4x4 Drivetrain

Hi all,

I have been reading about what type of oil for the differential to use other than available at the dealer. I was there this morning and they quoted me the price per liter US$ 75 plus US$ 35 for labor per hour, that is a total of US$ 225 for the oil plus tax plus labor. :bonk:

I have been asking around about 75w-90 Synthetic oil, and the best found here in Jordan are Liqui Moly and Wurth priced at US$19.

The dealer says that no other oil will be suitable for the transfer case and the differentials other than GM.

I did change the ATC oil at the dealer, for a cost of US$ 50 with labor at discount Promotion they have now.

Will any Synthetic 75w-90 will do, like I mentioned above. :confused:
The car have now about 88K.

Thanks to all, this have been a very helpfull forum.

Ghaith
 

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2004 chevy trailblazer_lt
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Whats the interval?

Hey!

this is my first post. what is the mileage interval for transfer case?I have an 04 Trailblazer with 122,000 miles...
 

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2003 chevy trailblazer_ls
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It is in you manual, if you do not have a manual you can download from the Resources button above. But to answer your question EVERY 50,000 miles.
 
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