1. Welcome To GMTruckClub.com!

    The #1 Chevy Truck Forum Online
    Online since 2004, we are the #1 Chevy Truck & SUV forum and user community. If you have any questions about your Chevy or GMC Truck, SUV or Crossover, or just want to connect with other GM owners and enthusiasts around the world, you've found the best place on the internet to do that.

    Join Today ~ It's Free
    Registering is Free and Easy! Hope to see you on the forums soon!

Front diff and t-case fluid change.

Discussion in 'Maintenance & Upkeep' started by Conlan Rose, Jun 12, 2013.

  1. Conlan Rose

    Conlan Rose Super Moderator 1000 Posts

    So some time next week I'm going to be replacing the fluids in both my front diff and transfer care on my 1996 Tahoe. The front diff calls for 80W-90 GL-5 gear oil and the t-case calls for dexron III or superseding. I'm gonna use dexron IV which should be the superseding fluid. It is not an automatic t-case.

    Any advice while doing this change?
  2. Pikey

    Pikey Moderator Staff Member ROTM Winner 1000 Posts

    The only advice I have is to make sure that you can get the fill plugs out before you drain them. I also use a piece of cardboard when I drain the front diff. I crease it down the center and lay it on an angle between the drain plug and my drain pan making a trough or ramp for the oil to roll down. This stops me from having to pull my skid plate or covering my skid plate in oil.
  3. Conlan Rose

    Conlan Rose Super Moderator 1000 Posts

    I'm doing it on a lift at school so removing the plate is easy, its a size 15 mm. I always remove the fill before the drain. Just need to make sure my friend helping knows the same. Do you know the approx size of the t-case drain and fill plugs because they look very large...
  4. RayVoy

    RayVoy Active Member 1000 Posts

    I agree, you do not have an auto t-case; however, if you have push buttons (and not a shift lever on the floor) you still have clutches. These clutches need Auto Trak II fluid. If you have a manual floor shifter, the ATF will probably work.
  5. Conlan Rose

    Conlan Rose Super Moderator 1000 Posts

    I have the push buttons. So you are saying I should use the Auto Track II not the Dexron IV. Poop that would make this change 10x harder because no one sells it in the area. Advance and autozone don't stock it and I don't have an O'Riley's. So the only place to get it would be Chevy where they would mark it up.

    BTW in the description of the product it says for Automatic T-cases not regular ones, but since my truck was built in a time of t-case design change I have no clue.
  6. RayVoy

    RayVoy Active Member 1000 Posts

    My understanding is manual or clutches. The fully auto cases (like in a Caddy) are not much different from the push button case that you have, they use the same clutch packs. Again, as I understand it, the clutches need the additives that are in the Auto Track II.

    Try going to the NPG/NVG (I don't remember if New Process, or New Venture is the current name) web site, maybe they have more info.

    Do you have an Owner's Manual?
  7. dsfloyd

    dsfloyd New Member ROTM Winner 1000 Posts

    Usually I hate getting stuff at the stealership too but when I went for the autotrak fluid the price/qt was actually similar in price as any decent synthetic fluid.
  8. Conlan Rose

    Conlan Rose Super Moderator 1000 Posts

    My owners manual says Dexron III or superseding fluid. I have the NP241 electronic transfer case. The New Venture site says my product doesn't exist.....
  9. dsfloyd

    dsfloyd New Member ROTM Winner 1000 Posts

    I would think that if thats what the manual states you will be good. When did they even start using the Autotrak? Maybe the 1996 is pre autotrak fluid.
  10. Conlan Rose

    Conlan Rose Super Moderator 1000 Posts

    I think the first Auto-Trak T case was in 98 on the Tahoe and Burban.

Share This Page