Transmission Fluid

I know there are many posts about trans fluid but I have a question. Do ya'll recommend using the domestic multi-vehicle atf such as castrol that qualifies for the DEX III or use a fluid that is only DEX III and doesn't qualify for other fluids. For some odd reason Advance's computer and the castrol guide said to use DEX IV. Anyone know why they said this?

Because DEX IV is the lastest fluid. Any well known NAME brand fuild that is DEX III approved will be fine.

What year car do you have?

It is an 02 GT. That is listed in my signature but I guess I should have stated that. My bad. My manual had said DEX III but I wasn't getting it checked in the computer to make sure I hadn't mixed something up. Even the Castrol book they had listed DEX IV. Is the IV better? I understand that it is supposedly a synthetic (that's what a transmission guy told me) but didn't know what the difference was. Is the multi vehicle okay? I had saw it in the castrol but dad wasn't real sure. I haven't dropped the trans fluid in a vehicle so I don't have a whole lot of knowledge on the whole situation.

Just get a DEX III compatible fluid you will be fine. 6.5qts on a pan drop but buy some extra and DON'T throw away the reusable molded pan gasket :)

And DEX IV is full Syn.

And DEX IV is full Syn.

Do you recommend switching over to Dex VI? <-- Take note.

I appreciate the answer. I was just reading about the difference between III and IV. I'm sure the IV would be better to use but the III has done well so far and I don't see that the price difference is worth it with the amount of miles I have on the car. I have 150k as of right now. I don't know how much more I will get before I will probably need a rebuild. I have neglected the car for a while I guess and trying to do the things I should have long ago. Also off topic, but do you recommend putting a new fuel filter on? I just got finished putting fresh oil in and replacing a front valve cover gasket due to oil seeping on the exhaust manifold.

Dex VI? <-- Take note.


Whoops, LOL I'm not up on my roman numerals. DEX VI is fully compatible with DEX III so there should not be a problem bout I would stay with DEX III

Do you recommend switching over to Dex VI? <-- Take note.

Bob, I thought 4t65e's had problems with synthetic?

And to the OP, yes, change the fuel filter, and why did you repair your own valve cover. I think you might be covered under the recall for that same problem.

And to the OP, yes, change the fuel filter, and why did you repair your own valve cover. I think you might be covered under the recall for that same problem.

I probably was covered under it, but I've always been one of those people that say if you want it done right, do it yourself. I was a learning experience as well. I had never replaced one before that. Besides it only cost $12 for gasket + $8 for new wrench after I broke a cheap one I had trying to get a bolt off that I think GM put Loctite on from the factory so its not like I was out much.

Bob, I thought 4t65e's had problems with synthetic?

And to the OP, yes, change the fuel filter, and why did you repair your own valve cover. I think you might be covered under the recall for that same problem.

:lol:

I really don't know Tim. :dunno: I've heard mixed stories about using synthetic but we're still looking for guinea pigs. :uhoh: From what I've seen switching over to Dex VI might be OK so I might consider doing it.

On the valve cover gasket issue I changed mine a long time ago so taking it back to the dealership to have the recall performed would be worthless. Plus I don't like other people especially at the stealership working on my GTP.

From everything I have read on the newer atf's, there is no danger of switching to a newer dexron. From everything said, it is only better to switch. Also DEX III should be coming off the shelf soon so people will have to stop using it if they can't get it.

I would stick with Troy's advice. He's the trans guru here and his word is the gospel IMO. As bnaylor stated, there are pro's and cons to switching to synthetic fluids on high mileage vehicles, and I would hesitate to take the risk myself and possibly develop leaks like engine oils can. The Dexron VI seems like less of a risk from what I read, but.....