Drivetrain fluids specifications

[MAY03LT]

Front differential:

Fluid type: synthetic 75w90 (GM P/N 12378261, meeting GM Specification 9986115)
Capacity: 1.7 pints

Transfer case:

Fluid type: AutoTrak II (GM P/N 12378508, also listed as GM P/N 88900402)
Capacity: 2 quarts

Rear Differential:

Fluid type: synthetic 75w90 (GM P/N 12378261, meeting GM Specification 9986115)
Capacity:

02-03 - 4.0 pints

04-09
4.2 I6: 3.6 pints
5.3 V8: 4.3 pints
6.0 V8: 5.5 pints*

*Add GM P/N 1052358 or equivalent
2006: 4 oz
2007-2009: 5.5oz

Note: I6 EXT/XL members have reported a 5 pint capacity for the rear diff.

Note: 1 Pint = 0.5 Quarts (courtesy of HARDTRAILZ)

Transmission:

Fluid Type: DexronVI*
Capacity, pan removal only: 5 quarts
Capacity, total: 11 quarts

*DexronIII was used in the earlier models. However, GM recommends using DexronVI for all transmission services/top offs/flushes in all DexronIII applications. DexronVI is backwards compatible with DexronIII, however DexronIII is NOT forwards compatible with DexronVI.

Source: MOTOR specification guide 2011

IMPORTANT: DEXRON-VI Automatic Transmission Fluid (ATF) is the only approved fluid for warranty repairs for GM transmissions requiring DEXRON-III or prior DEXRON transmission fluids

Source: GM TechLink 5/09

2002-2005 torque specs (courtesy of Wyle):
Transmission pan: 10 ft-lbs
Front differential fill and drain plugs: 24 ft-lbs
Rear differential fill plug: 24 ft-lbs
Rear differential drain plug (if there): 35 ft-lbs
Rear differential cover (8.0" axle): 20 ft-lbs
Rear differential cover (8.6" axle): 18 ft-lbs
Transfer case (NVG126 or NVG226) fill and drain plugs: 20 ft-lbs


Side notes (courtesy of Tofer76 and jbones):
the rear diff drain (if equipped) and fill bolts are a 3/8" drive
the transfer case drain and fill bolts are a 10mm hex (allen)
the front diff drain bolt is 13mm, fill bolt is 18mm.

Front Differential drain and fill plugs (from The Roadie):

View attachment 17799

 

[HARDTRAILZ]

Public schools suck these days and since most fluids come in quarts...

1 Pint [US] = 0.5 Quarts [US]

 

[Wooluf1952]

I thought all the LWB's have the bigger rear diffs. Not just the 5.3.

 

[MAY03LT]

I thought all the LWB's have the bigger rear diffs. Not just the 5.3.

Now that I think about it, I'm pretty sure that I had to open a third bottle of gear oil for an 03 SWB that I did not too long ago. Like the other threads, I cross referenced this info to another automotive information provider and everything matched.

I will make the necessary changes to the post once more info is available.

 

[Wyle]

NICE. Read it just before I was about to change transmission fluid and switched to Dexron VI.

Would be nice to list the relevant torque items as well.

What I found for (2002-2005 at least) are
Transmission pan: 10 ft-lbs
Front differential fill and drain plugs: 24 ft-lbs
Rear differential fill plug: 24 ft-lbs
Rear differential drain plug (if there): 35 ft-lbs
Rear differential cover (8.0" axle): 20 ft-lbs
Rear differential cover (8.6" axle): 18 ft-lbs
Transfer case (NVG126 or NVG226) fill and drain plugs: 20 ft-lbs

 

[djthumper]

NICE. Read it just before I was about to change transmission fluid and switched to Dexron IV.

Dexron IV? I hope you meant Dexron VI...

 

[Wyle]

Dexron IV? I hope you meant Dexron VI...

Oops. Exactly. Dex VI (corrected). I refuse to be lysdexic.

 

[rmsg0040]

Should mention, autotrak II is dealer only

 

[Wyle]

Should mention, autotrak II is dealer only

GM part # 88900402
Available through a few online places as well. GMpartseast.com=$6.04; summitracing.com=$6.69; partszoneonline=$6.02; GMpartsdirect=$5.25 (but you have to buy a lifetime supply of 12 quarts = YOUR lifetime, not a vehicle).

Probably not worth paying shipping costs, but if you're getting parts from them, you can always add a couple quarts to the order for next drain.
Also an option for those with no stealership nearby.

Oh, and riversidegear.com Its "ON SALE" for $14.95 and (surprisingly) in stock.

 

[Mark20]

When I had my mechanic do my diffs and transfer case (and then I find how relatively easy they are to do) the Envoy had to sit on the lift for a day while he ordered more Auto Track II from a supplier.

With the running boards I'd probably have him do it again because they make getting underneath the middle portion almost impossible.

Sent from my Xoom using Tapatalk

 

[Tofer76]

i have a 03 envoy xl and just did all mine last week and found the following:

rear diff takes 5 pints not 4 like all the manuals say
front diif takes 1.5 not 2.7 " " " " " "

the transfer casr tho is right on at 4 pints or 2 qts

when i did mine i had plenty of time so i had all 3 draining over night into seperate containers and then checked each with a mirror and light to look for any problems then refilled

side note: the rear takes your 3/8 drive ratchet w extention
the trans case is a 10mm allen wrench (i used socket one )
the front is 2 wrenches cant remember what size right now

 

[jbones]

...the front is 2 wrenches cant remember what size right now

Drain bolt is 13mm
Fill bolt is 18mm.

 

[tblazerdude]

from experience, I strongly recommend 6 sided/6pt. wrenches/sockets for the front diff.

they also sell a tool (very similar to your extensions) that has a slightly tighter fit for the rear diff plugs. Might be handy to know that there is a real tool, if you feel like your rear diff fill plug wont turn.

 

[zamimj222]

from experience, I strongly recommend 6 sided/6pt. wrenches/sockets for the front diff.

they also sell a tool (very similar to your extensions) that has a slightly tighter fit for the rear diff plugs. Might be handy to know that there is a real tool, if you feel like your rear diff fill plug wont turn.

Where do you get the tool at for the rear diff? I was able to get it out to do the servicing, and torqued to 24 ft lbs and now can't get the little rascal out... almost have it stripped...... so I stopped...

 

[zamimj222]

Where do you get the tool at for the rear diff? I was able to get it out to do the servicing, and torqued to 24 ft lbs and now can't get the little rascal out... almost have it stripped...... so I stopped...

talked to the dealership in my area and they said the numbers changed from 12378261 which was a 32 oz bottle to 88900402 which is a 33.8 or 1 ltr bottle. this was only to make it a little easier for us do it yourselfers...... i was told that the transfer case takes only 1 ltr of fluid by the dealership, not 2 qts as previously stated earlier. can someone verify this is correct?
Thank you!!!!

 

[HARDTRAILZ]

talked to the dealership in my area and they said the numbers changed from 12378261 which was a 32 oz bottle to 88900402 which is a 33.8 or 1 ltr bottle. this was only to make it a little easier for us do it yourselfers...... i was told that the transfer case takes only 1 ltr of fluid by the dealership, not 2 qts as previously stated earlier. can someone verify this is correct?
Thank you!!!!

Having changed my TC fluid a few times. I always use two and have NEVER heard of any other amount being called for.

They may have looked up the front diff which is just over 1 quart on fluid.

 

[zamimj222]

Having changed my TC fluid a few times. I always use two and have NEVER heard of any other amount being called for.

They may have looked up the front diff which is just over 1 quart on fluid.

The dealership was wrong??? lol Last time I changed it, I bought 2 qts and had a little left over. Damn parts guys must not have had enough coffee this morning. Glad I checked here before I went to buy the stuff today. Thanks bud!!

 

[ND-1965C10]

from experience, I strongly recommend 6 sided/6pt. wrenches/sockets for the front diff.

they also sell a tool (very similar to your extensions) that has a slightly tighter fit for the rear diff plugs. Might be handy to know that there is a real tool, if you feel like your rear diff fill plug wont turn.

This was asked before but I don't see that it was answered here at least:

Wondering where I can buy this tool, my plug seems like it has to be welded in (really stuck!). I was afraid of rounding it out when tried with an impact.

 

[tblazerdude]

Here's one.

http://m.harborfreight.com/12-piece...t-94961.html?utm_referrer=direct/not provided

 

[The_Roadie]

They can indeed get stuck. Often you can improve your odds by heating up the surrounding area a bit with a torch. Any parts store should have a plug removal tool. Just go look or (shudder...) ask.

Usually a 3/8" extension is not the optimum tool because the end is rounded or has a spring-loaded ball embedded in it that weakens it. You can find short extensions without the spring balls if you look, and you can also grind off any rounding to make the end square. I've seen special tools you can also find using the search term "pipe plug socket" like this SK tools 41449:

View attachment 31799

 

[Tofer76]

also when you do get it out, make sure that you anti-seize it before installation and the front diff fill plug is easily accessed with the front wheel off just need a 6point socket and 2 6 in exts on a ratchet

 

[Chris JW]

I dont know what a dealship charges for auto-trak II
but i found this and imagine its a bit cheaper than a dealership
hope this helps someone out if they are reading this thread and they need to change fluids

http://www.oreillyauto.com/site/c/detail/ACDD/104017/N2623.oap?ck=Search_N2623_-1_-1&pt=N2623&ppt=C0207

 

[The_Roadie]

Normal dealer list for the fluid is around $12 a bottle. We've heard of dealers charging up to $35 for the stuff. Unconscionable.

Amazon also has it for just under $9 a bottle, which is great if you have the Prime membership.

 

[dla442]

I get autotrak for five bucks a quart at a local gm supplier that I managed to squeak in an account at...wholesale baby

 

[The_Roadie]

OK, then, good buddy! What's your shipping charge and Paypal address so you can be the new GMTN supplier?

 

['03EXT]

Thanks roadie... Just ordered 2 autotrak II from amazon, $18.55 to my door in 2days( yes and thank you amazon prime). ......I looked it up a few days ago and they were selling it for $12.46 , today they have it for $12.46 and $8.67 for the same item must be a fluke that the are selling the same item at such different prices[emoji106]

 

[TB_n00b]

Has anyone tried a 10 mm pipe plug socket when removing the rear diff fill/drain plugs? The difference is <0.5 mm. I've tried 4 different stores and none have a 3/8" square tool. Only 10 mm at Pepboys

 

[RayGumm]

Has anyone tried a 10 mm pipe plug socket when removing the rear diff fill/drain plugs? The difference is <0.5 mm. I've tried 4 different stores and none have a 3/8" square tool. Only 10 mm at Pepboys

I would NOT recommend doing this. There is a high likelihood that it will just strip the square hole in the plug out and then you'll really be screwed...
if you can't find or wait for the proper tool to be delivered from ordering online, just use a 3/8" socket wrench with a 3/8" extension and use that. Way less likely you will strip anything out, especially if the extension is of high quality. This is what I did. You can also flatten the end of the extension on a metal sander or some such device so the end of the socket extension bottoms out into the plug, which will also help it 'bite in' and lessen the chance of it popping out or stripping anything.

Luckily mine was not too tight and with just a little elbow grease and a 6" extension, it came right out.

Good luck!

Trailblazer rear differential fluid check/drain/f…: http://youtu.be/5XP7v3ezv-0

 

[TB_n00b]

Just FYI, 10 mm is larger than 3/8 and no, there is not enough tolerance to allow for the <0.5 mm difference. Luckily among my father's tools is an older 3/8 rachet with sharp corners. Needed a breaker bar but for it out. It's drained. Filling the diff now.

 

[chucki]

so auto trak 2 is a fluid like transmission fluid and not a gear lube like the 75 -90? how long will the factory fuel pump last?

 

[Mounce]

so auto trak 2 is a fluid like transmission fluid and not a gear lube like the 75 -90? how long will the factory fuel pump last?

Yes it's similar to transmission fluid but they're not interchangeable. The transfer case is very picky, almost delicate, and requires proper care to stay functional. Some peoples fuel pumps will go out at 70,000 miles and some people are still running on the original one at 200,000 miles.

 

[chucki]

have 2 qts of auto trak 2 coming from o'reillys. am gonna try to put life time warranty sway bar links grease able from o'reillys on my 2004 , are cheap china made but if last a couple of years and replace for free will be able to do that easily. have a panama city trip planned for early oct. and am planning on driving my new to me TB. 600 miles one way. need a new battery. plan is to use my riding lawn mower battery to keep comp. up while install new batt. yes no?

 

[Mounce]

What components are you worried about keeping up? Or what do you mean by that? If you're worried about the computer memory and such, the battery will only be out a few minutes and that isn't long enough to reset things in it so you'll have nothing to worry about other than the time and radio presets which will be lost. Seems like everyone recommends turning the hvac controls to off before disconnecting the battery, though.

 

[chucki]

was under the impression that if disconnect batt then the puter thinks the intake butterfly is dirty and misses. can turn a/c off no big deal. just hearing others talk, buddy at work. new battery and had to get systems reset. just wondering. need no issues as is wife's main ride.

 

[Mounce]

was under the impression that if disconnect batt then the puter thinks the intake butterfly is dirty and misses. can turn a/c off no big deal. just hearing others talk, buddy at work. new battery and had to get systems reset. just wondering. need no issues as is wife's main ride.

Your buddies battery must've crapped out and lost voltage or he took it out then left it out for a while or took a different vehicle to town to get a new one. It normally takes around 30 minutes for the computer to reset and cause the idling issues. So, if you get the battery, go home, and do the job in one go, you'll be fine. What I mean by "one go" is: when you unhook the old battery, put the new one in as soon as you can, don't take a break and leave everything unhooked. If you're taking the car to a "batteries plus" or similar battery dealing shop and letting them change the battery it should be no big deal and nothing to worry about with the computer.

If your buddy is still having issues, tell him to clean his throttle body. And if you have issues of stalling afterwards (which you shouldn't) then clean yours too.

 

[paul2005tb]

Transmission:

Fluid Type: DexronVI*
Capacity, pan removal only: 5 quarts
Capacity, total: 11 quarts

*DexronIII was used in the earlier models. However, GM recommends using DexronVI for all transmission services/top offs/flushes in all DexronIII applications. DexronVI is backwards compatible with DexronIII, however DexronIII is NOT forwards compatible with DexronVI.

Source: MOTOR specification guide 2011

I dont doubt the GM specification for DexronVI in place of DexronIII and I wouldnt advocate anyone sticking with the DexronIII .. but...

but.. if you read the specifications on these fluids the key difference is the lower viscosity of the DexronIV,V,VI.

(My source was the wiki page.)

This lower viscosity was chosen to reduce drag and improve engine efficiency.

I have not read anything suggesting that the DexronIII is less effective at lubricating the transmission or protecting the components or extending the life of the transmission. If fuel efficiency is important to you, certainly go with DexronIV and beyond.

Im also inclined to lean towards thinking that the MFG recommended viscosity of our motor oil is driven a bit on the light side by the desire to increase fuel economy and not necessarily extending the life of the engine.

I welcome corrections and perhaps this is not the place to discuss this issues.