Which fluid for new trans and differentials?

[Shad0wXCalibur]

Certainly do go with whatever you're comfortable with. Just for me personally, I can't justify spending almost twice as much for probably the same fluid. I used nothing but Supertech's ATF+4 in my first car, a Dodge Neon from 130,000 miles to 210,000 miles. Transmission never had a problem. I've used Supertech Dex 3 in my wife's Saturn from 78,000 to 125,000 miles. Still operates smoothly with very little grit on the magnet between changes. My dad uses their Dex 6 in his 2000 Silverado. He got it brand new and it has 115,000 miles now with no issues at all and he has towed all kinds of stuff over the years with it. He says it always stayed red with no "burnt smell". The stuff is just rebranded. It could be Valvoline or Castrol for all we know but it's worked for me... Just thought I would share my experience with the stuff. The only time I had an issue was with my 94 S10. It started slipping badly but that would have happened with any fluid. It had 232,000 miles, no cooler, previous owner left burnt fluid in it and always towed a boat with it so I think running fresh fluid through it kinda messed it up.

[KC10Chief]

I talked to the rebuilder today. He said he did not recommend Dex 6 for this transmission. He says it's too slippery for the friction pads in the transmission. He said he recommended Valvoline Synthetic Dex 3. What say you guys? I don't think he's rebuilding it with any sort of unusual pads. I'm picking it up tomorrow and will ask more questions. I plan to install it on Friday after I wake up from my turkey coma! Can't wait!

[Phantom]

Here is the GM TSB on the introduction of Dexron VI
I have used DEX VI in even older cars and could notice a better shifting pattern ,

The fluid change intervals is to remain the same as the model year of vehicle it is used in
Change the fluid at the recommended time intervals of the 97 astro owners manual

Often in small private shops they tend to forget about the latest TSB , and want to avoid customers coming in and complaining " you told me ........" "the owners manual said......." etc etc. because car owner does not typically have access to TSB , for shops to stick with what ever was originally used is a good way for the shop to cover their own ***.....synth dex 3 will be fine ..and DEX VI is fine , the most important thing is to keep fluid cool and changed on a regular basis .

How the builder is able to tell the difference in what is too slippery is what I'd like to know , synthetics by nature are more slippery;; syhth dex 3 is going to be more slippery than regular
dex 3 .

[Leeann_93]

I agree with everything, especially the part where synth Dex III is more slippery than Dex VI.

I'd use Dex VI...

[Phantom]

I was looking into the synthetic dexron 3 matter and realized that the Licensing fro dex 3 has long since expired and will NOT be renewed .

Which leaves the door wide open for companies to make a formulation that may not actually conform to the requirements of dex 3 and no one would ever know because it is no longer tested or policed over to determine if a product violates conformity since now there is no license to conform to , Seems there is no official synthetic dexron 3 standard , just whatever any company wants to make it and call it what it what they want .

[KC10Chief]

Fantastic information! I really appreciate it! Dex 6 it will be!

[Shad0wXCalibur]

I've never heard of Dex 6 being a problem in the 4L60E. Now I did find something somewhere from GM themselves that mentioned not using it in Saturn's S-Series. So that's why I still pump Dex 3 in my wife's car.

[KC10Chief]

I picked up a case of Valvoline synthetic Dex VI tonight for $120! Ouch!

I realized something tonight and don't know if it's a problem or not. When I was taking my transmission out, I removed the transfer case. There was quite a bit of fluid that came out of the side where it meets the transmission. Is this normal? I don't have access to my van or the transfer case until Friday. If I'm not mistaken, there is a seal on the input shaft, correct? So, should there be transmission fluid between the transfer case and the transmission? It was also coming out the other side when I removed the drive shaft. That's normal though, I think. What say you guys?

[Leeann_93]

The seal on the output shaft of the tranny was bad. Should have been replaced in the rebuild.

[KC10Chief]

I was wondering about that too. I didn't even think about it when I took it apart that there shouldn't be transmission fluid in that cavity. I only realized it yesterday. I can't check my transfer case, which also takes transmission fluid. It's locked up until Friday. I'll probably go ahead and buy a seal in case I need it. How about the seal on the back of the transfer case where the drive shaft slides in? Is it normal for it to leak fluid without the drive shaft in there?

[Leeann_93]

I'm not sure there is a seal there that could allow fluid out of the t-case. On a Blazer or Bravada, it is ALWAYS the output seal on the tranny that failed in that case (thousands of threads).

[worldtriad]

Transfer cases on my 1999 Astro van don't take transmission fluid that I'm aware of. Last time I had the transfer case fluid changed, I bought the GM Auto-Trak II Transfer Case Fluid directly from the dealership for around $6 a liter. I bought 5 liters I think. Some things I'd rather get GM/Delphi/AC Delco on and am willing to pay whatever. That was a better price than my mechanic could have gotten.

Heather
++++++++++++++++++++++++++++++++++

I was wondering about that too. I didn't even think about it when I took it apart that there shouldn't be transmission fluid in that cavity. I only realized it yesterday. I can't check my transfer case, which also takes transmission fluid. It's locked up until Friday. I'll probably go ahead and buy a seal in case I need it. How about the seal on the back of the transfer case where the drive shaft slides in? Is it normal for it to leak fluid without the drive shaft in there?

[Leeann_93]

As I said in my first post in this thread, up to '98 takes Dexron. '99 and up takes GM AutoTrak II, which you can only get from the dealer.

[Chevymankevin]

I have been contemplating changing my trans fluid on my 95 RWD. The trans was rebuilt aprox 5 years/ 30-40K ago and im not sure what they put in it. Would it be wise to do a drain and fill change the filter and put in the new Dex? I know I wont get
%100 of the old fluid out by drain and fill method. Will it be safe and effective if the two types of Dex mix?

[Phantom]

:goodpost:

I have been contemplating changing my trans fluid on my 95 RWD. The trans was rebuilt aprox 5 years/ 30-40K ago and im not sure what they put in it. Would it be wise to do a drain and fill change the filter and put in the new Dex? I know I wont get
%100 of the old fluid out by drain and fill method. Will it be safe and effective if the two types of Dex mix?

Yes it will be a great idea to change filter and fluid !

Dexron VI is the recommend fluid , yes it is fully compatible with what you already have in transmission , you will drain out about half of the fluid and the other half will be in the torque converter

If you read through this thread you will see the GM published statement to use DEXRON VI

[paintdrying]

How would one spot unlicensed or counterfeit dex 6?

[Phantom]

For the best answer to that question I would have to look up some stuff

but the licensing is usually acquired by the major brand names , it is a very tight set of specification test criteria the fluid must pass , it has been tested to be within spec of the criteria , the ability to resist foaming at pre-defined temperatures and things like that , making sure that it is high grade quality to perform to specific standards

to ID unlicensed or counterfeit dex 6 would be seeing things like :

"suggested for use where ..." "multipurpose ...all in one ...suitable for... type language that implies that it is ok to use it with dex6 , with this legaleeze type stuff a variety of wording may be used ,

The most common way to know if it is licensed is , the product will have some wording written on it such as :

GM licensed product

licensed to conform to GM xxxxx1234567 standards

some type of wording that clearly states it is licensed or
has passed GM test standards xxxxx1234567 etc etc

[Chevymankevin]

So I went to the TSI trans shop that rebuilt my van's trans back in 07 and asked him a few questions. He says the new dex is a great fluid but it will cost me. They said a trans flush would run me double about $220 if I use the new dex VS dex III. But he said just dropping the pan and filling would be fine since I only have 40K on the rebuild. I cant ever seem to finish the list of things that I want to accomplish/need to be done with my van!

[Lumpy]

... I cant ever seem to finish the list of things that I want to accomplish/need to be done with my van!

For me that statement is the definition of owning a vehicle like we do.
If I didn't have an unfinished list, it would be because the van was dead and gone.

If I didn't want to work on my car, I'd lease one.

I don't ever want to "finish"...


Lump