Ironmike4x4

I am about to service my transmission at work Monday and Alldata says I need either DII or Dexron 3 fluid in it. Which one is it? At GM we have a specific fluid type for different transmissions. Also do they make either one of them in synthetic? I thought about running Redline like everyone here has talked about. Any help is appreciated.

Ilovemountains

Mike I would run Mobile1 Full synthetic. Ive been using if for a long time and my truck shifts like new even at 152,000! Its nice becuase cold weather doesnt bother it, so it doesnt get thick and make the trans act sluggish cold. Just my opinion though! Before I switched I ran the Quaker State speacial import formula.

Robinhood150

Like it said, you can use either just fine. However, nobody make dex2 anymore so you have to get dex3. Also, are you just doing a drain and fill, or a complete flush. A full flush takes about 15 qts. and you need to pull off the hoses to do it.

mattyfatty182

So mixing DexII with DexIII won't hurt it, right?

I'm just gonna be draining and then refilling it, not a full flushing.

Ironmike4x4

Oil in trans fluid? I dont know about that... but anyways, I just want to run Dex 3 synthetics if there is a such. I do have acess to a transflow machine so I am going to do that while I am at it just to clean all that crud out, but I will be running regular dex 3 to keep from wasting mine then pour the synthetic in.

Robinhood150

I think he's talking about Mobile 1 synthetic ATF. http://www.mobil1.com/index.jsp

You've got lots of choices for tranny fluid, redline, mobile one, amsoil, etc. This particular board likes amsoil.

Mikey

This raises a good question. The manual calls for my truck Dextron III. But good luck trying to find it anymore. I can't remember But when I did my tranny flush I had to use Dextron IV or V. What about switching to the Toyota II fluid ( I think that's the number )? Is that safe to do?

Ironmike4x4

They do still make Dexron 3 and just for the record... make sure it says dexron and not dexTron that was the knock off version of it a few years back is what I am told. And thanks for clearing that up about the Mobil one trans fluid. I wasnt aware that they even made tranny fluid but I've always had good reports of mobil oil so I may just run that and see. Thanks for all of your help.