Hi, I just changed the front and rear diff. fluids. The ? is on the capacity, this site say's 2 qts in front and 4 in rear. I put 3 in the front and 3 in the rear and according to the manual, the levels should be from 0 to 3/8"for (front),or 0 to 1/2"(rear) down from the filler plug, Both are within theses numbers, Is there that much variations from what has been posted on this site ? Should I add 1 more qt. to the rear axle ? Also I changed the transfer case oil and put auto-trak II in it,like the manual says. Is this right or should I have put Dextron III ? Thanks

Hi, I just changed the front and rear diff. fluids. The ? is on the capacity, this site say's 2 qts in front and 4 in rear. I put 3 in the front and 3 in the rear and according to the manual, the levels should be from 0 to 3/8"for (front),or 0 to 1/2"(rear) down from the filler plug, Both are within theses numbers, Is there that much variations from what has been posted on this site ? Should I add 1 more qt. to the rear axle ? Also I changed the transfer case oil and put auto-trak II in it,like the manual says. Is this right or should I have put Dextron III ? Thanks

I can't see how you got that third quart in the front.Mine was spilling out after 2. Yes to adding the fourth quart.I like to add until it's spilling-My finger doesn't come in 1/8'' gradations.The manual is right for the ATF

I can't see how you got that third quart in the front.Mine was spilling out after 2. Yes to adding the fourth quart.I like to add until it's spilling-My finger doesn't come in 1/8'' gradations.The manual is right for the ATF
x2...

How did you get 3 quarts into the front? Mine also only holds 2.

I sure can't understand how, but I used a suction gun and put all 3 qt's in, with very little left after draining what was left in them into the last one. It never came out the fill plug hole and I can stick my finger in and touch the oil level, within the spec of 3/8" down. I am not new to working on vehicles. I will try and add 1 more Qt. to the rear end and double check the front again. I may end up draining it again but I am baffled by this.

Hey guy's, Buyer's BEWARE. After I scratched my head a few more times after the last post I called my Dad up and had him check the recycle bin with the oil containers in it, that I had used and found the problem. The oil GM sold me # 89021671 for the front axle was only 23 oz ???, I can't believe that they did not know or tell me, so I will be getting one more to top it off. I sure hope this helps more people out to really check things out and not assume that they are 32 oz or 1 qt. size and only end up with 23 oz instead. Thanks for all the input.

Hey guy's, Buyer's BEWARE. After I scratched my head a few more times after the last post I called my Dad up and had him check the recycle bin with the oil containers in it, that I had used and found the problem. The oil GM sold me # 89021671 for the front axle was only 23 oz ???, I can't believe that they did not know or tell me, so I will be getting one more to top it off. I sure hope this helps more people out to really check things out and not assume that they are 32 oz or 1 qt. size and only end up with 23 oz instead. Thanks for all the input.

I knew something was amiss here.Very strange way of packaging--23oz.-Next time,get a better product and much cheaper to boot by using Schaeffers 75/90 syn.

I would suggest rechecking the fluid for the transfer case, auto-trak is for automatic t.cases (NP8/four button switch). I think you have an NP1, which has the 3 button switch. Better safe than sorry.

Yes I do have the 3 button 4x4 switch, but in the diesel supplemental manual it say's for automatic transfer case use auto-trac II fluid, # 12378508, but I think that number changed. Should I use dextron III ? Thanks

Check the RPO list in the glove box..if you see NP1 in the list, which I believe you will, your t.case uses Dex.III. Autotrac is used with the NP8 option. Both the t.cases are considered automatic, because the shift electrically. However the NP8 has the auto engage design which has a 4 button switch and clutches inside it. The automatic option allows the front diff to be engaged and only engages the t.case when wheel slip is detected. To my knowledge this is not used on the Dmax. The clutches can't handle the torque.

Yes you are right,. it is the NP1 option, I will be changing to Dextron III very shortly. I just can't understand why it would be listed that way ( auto-trac II ) in the diesel sup. manual ? Also I changed the dextron III in the tranny but I did not look on the bottles for the ( "approved for the H-Specification" on the label ) Like it say's in the sup. manual also, Is there 2 types of Dextron III fluid ? Or should it be on all dextron III bottles ? Thanks

FWIW, my 2007 2500HD with 6.0 has the NP1 (NVG 263HD) Transfer Case and the manual calls for Auto Trak for the Automatic Version (3 or 4 button electric shift) and Manual Transmission Fluid for the standard (floor shifter) version.

No mention of Dexron III or any other ATF.

You can verify for yourself on page 26 of my scan of the manual here:

http://www.pirate4x4.com/tech/billavista/Chevy/Silverado.pdf

I just verified with GM service information. This is a c/p from Document ID 1752854, NP1/NP2/NP3 Transfer Cases all use GM manual trans fluid. I made an error, I apologize. This is new for '07 Silverado/Sierra Classics. The NP8 option which still uses a clutched t.case gets the auto-trak.

--------------------------------------------------------------------------
Approximate Fluid Capacities
Application
Specification

Metric
English

Manual Transmission Fluid GM P/N 88861800 (Canadian P/N 88861801)
1.9 liters
2.0 quarts



--------------------------------------------------------------------------
Document ID# 1752854
2007 Chevrolet Silverado Classic - 4WD

Furthermore A GM PI that was released in Feb 07 states this fliud should be used in place of Dex III in manual transmission and t/case applications only. The NP1 is not considered an automatic transfer case by GM only the NP8 is. NP1 is an electric shift, manual transfer case. Also this manual fluid is red like dexron...don't get confused. Once again my apologies for my previous post of incorrect info, I wasn't aware of this change.

So anything thats not 07 and newer still uses Dex III in the T-case, correct?

I need to re-read the PI again to be sure, but I think the manual trans fluid is to be used in place of ATF in all prior t.case and manual trans applications that call for dex III. I'll post more info on Monday. However if it calls for dex VI...still use it.

I just did my front diff and transfer case. The front took 2 quarts and so did the transfer case. Used Valvoline gear oil in front, don't have the white cap so I used non-syn. and Dexron III Castrol in the transfer.
Last time I had it done at dealer when I had some warranty work done and I looked at the receipt from 2004 and wished I had known then the capacity then. They charged me for 3 quarts for the front diff and 4 quarts for the transfer case.

The front fluid came out black like sludge. flowed out fine but the last 1/2 quart was very thick.

Sorry I forgot to finish-dexron 6 is not to be used in the transfer case. And the manual transmission fluid in the bulletin is considered a dexron 3 compatible fluid. Seems like a big runaround, but the big thing is t.cases get dex3 or equivelant fluid only, not dex6.

You probably could run Dexron VI in the transfer case as it's the same as III,except for some enhancement for the Ally.Not sure though.Any GM techs care to elaborate?

X2, and yes 23oz cans.

No, do not use Dex VI in the GM transfer case!! That was what the bulletin was about. Dex III and Dex VI are not the same and they do NOT mix. The Dex VI is not compatible with the case components, the bulletin states corrosion or t/case failure may result. To my understanding Dex VI is a semi-synthetic fluid and is not just an enhanced Dex III.

This makes no sense.Why would any ATF lead to corrosion?It's in our Allys from the factory so what possible harm could it lead to in the transfer case?I'll talk to my service mgr. soon to see what he says.

I checked the PI again this morning and it has been superceded....here is the latest version. Although the underliying issue is still the same. Dex III and Dex VI do not mix. The important note in the middle is all that really changed. It just states that unless you transfer case calls for Dex VI according to the manual...it still needs a Dex III equivelant fluid.

Document ID# 1897292
2007 Chevrolet Silverado Classic - 4WD

http://service.gm.com/engif/000/999/999/999999995.gif Subject:Manual Transmission Fluid Usage In 2007 And Prior Manual Transmissions And Transfer Cases - keywords case fluid manual transmission transfer #PIP3836B - (02/05/2007)


Models:2007 and Prior Passenger Cars and Trucks
2007 and Prior HUMMER H2
2007 HUMMER H3
2007 and Prior Saturn Passenger Cars and Trucks



This PI is superseded to add a note under concerns. Please discard PIP3836A.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1897292&psdid=1636&evc=sm#ss1-1897292">Condition/Concern:

Use of manual transmission fluid part number 88861800 U.S. (88861801 Canada) in place of Dexron III.
Important Note: If the vehicle owners manual lists Dexron VI as the recommended transmission, transaxle or transfer case fluid disregard any information supplied in this PI. Use eSI and or the vehicle owners manual to determine what type of fluid should be used prior to referencing the below information
<A href="http://service.gm.com/servlets/BlobShtml?ShtmlFile=1897292&psdid=1636&evc=sm#ss2-1897292">Recommendation/Instructions:

Manual Transmission fluid part number 88861800 U.S. (88861801 Canada) is currently available through GMSPO. Current and past model vehicles listed above with either a manual transmission or transfer case that REQUIRE Dexron III should use the above listed manual transmission fluid. This fluid is a direct replacement for Dexron III in manual transmissions and transfer cases. DO NOT use Dexron VI in place of the manual transmission fluid in any manual transmissions or transfer cases as a failure may result.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
http://service.gm.com/engif/000/999/999/999999994.gif WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

© Copyright General Motors Corporation. All Rights Reserved.
Document ID# 1897292
2007 Chevrolet Silverado Classic - 4WD

I just looked in my 2006 GMC Sierra Owners Manual and I can find NO mention of any transmission fluid with P/N 88861800 as stated in the above document.

Which manual transmission are they referring to in the document?

My Owners Manual says the following:

Manual Transmission (5–Speed with Low Gear, RPO MW3)
GM Goodwrench® Synthetic Manual Transmission Fluid (GM Part No. U.S. 2346190, in Canada 10953477) or equivalent SAE 75W-85 GL-4 gear oil

Manual Transmission (5–Speed without Low Gear, RPO MG5)
Synchromesh Transmission Fluid (GM Part No. U.S. 12345349, in Canada 10953465)

Manual Transmission (6–Speed)
Synthetic Transmission Fluid approved to Allison Transmission[® specification TES-295 (GM Part No. U.S. 12378515, in Canada 88900701) (NOTE: This is TranSynd.)

Automatic Transmission
DEXRON® -VI Automatic Transmission Fluid.

Since TranSynd is Dexron III compatible, can I use TranSynd in the transfer case?

This makes no sense.Why would any ATF lead to corrosion?It's in our Allys from the factory so what possible harm could it lead to in the transfer case?I'll talk to my service mgr. soon to see what he says.

Looking this over it would seem from the next two post that GL4 designation is the issue as it is required for anything with brass bushings, GL5 has additives that will harm brass bushing and I'm guessing that the dex vi atfs do also. Another post is running that has a reccomendation of regular crankcase oil but that has no antifoaming additives so it can't be good.