Mixing different ATF's? okay or not?

[RegDunlop]

I have some Maxlife ATF that states DEX VI and DEX III on the label, some Maxlife that states DEX III on the label ( I assume these bottles are older stock) and some Pennzoil that is speced for D/M ( for older GM vehicles that used DEX III).

I have a 95 GM 4T65E transmission.

My question is it okay to mix all of these ATF's?

I plan on extracting the old, drop pan and filter refill, and then only extract and replace a bit more of the fluid to try and get a greater percentage of the old fluid out.

Is it okay to mix all of these fluids?

Which should I save for the last fill? The Maxlife or the Pennzoil?

 

[AstroTurf]

Yes, You can mix atf fluids that meets your vehicles specifications.

Second question... Which ever one you like best.

Hope this helps, Jim

 

[JHZR2]

You can, would I? Not if I could help it. It is tough with an AT though. Would long-term try to do enough swaps to have mjaority of fluid from one maker.

How to swap it? Start with the pennz. move to the older maxlife, and ultimately swap in the dex VI maxlife.

 

[dtt004]

Hi.

Mix them all with no worries. Have fun!

 

[Whitewolf]

You should not mix fluids unless you know what you are dealing with. Basic chemistry manuufacturers, all different, Afton, Infineum, Lubrizol. What are you mixing?

Dexron -III fluids were by and large ok to mix but remember that in those days the performance window was quite wide.

With the advent of DEXRON-VI and other specialised fluids mixing at random is not to be advised. It may be that if you are not stressing the transmission too much you can get away with it but it is not the ideal.

 

[JTK]

No worries at all given the two versions of Maxlife you're referring to.

Any time you change your transmission's ATF you're mixing ATFs.

Joel

 

[Whitewolf]

Do you know the specific formulations and the chemistries involved along with the treat rates of course?

How much of your knowledge are you able to share?

 

[JTK]

Originally Posted By: Whitewolf
Do you know the specific formulations and the chemistries involved along with the treat rates of course?



I don't know the specific formulations and chemistry any more than you do, nor do I understand your paranoia associated with it.

We're talking three 'universal' ATFs here, not to mention a very mass produced GM transmission that has proven to function perfectly on any universal ATF. Any time someone does a pan drop and filter change they're mixing ATFs.

Joel

 

[Whitewolf]

There is no paranoia ... I just happen to know about different ATF chemistries and what happens when you mix them. If you want me to help you understand I can go into a lot more detail, but it looks like you don't so I'll just end this by saying, publicly, that you should NOT ideally mix ATFs unless you know the specifics of the chemistries involved.

 

[Stu_Rock]

Whitewolf, you should go into a lot more detail.

 

[crinkles]

I am about 40% amsoil 60% T-IV at the moment. Going back to T-IV in 10,000 miles.

 

[Pablo]

I actually agree with Whitewolf here. I am not a big fan of mixing ATF's. While I don't think it's acutely harmful, it's certainly not ideal and in fact kinda lousy. There is more than one method (via a chemical blend) to ATF nirvana. Either fluid might work great. But if mixed, neither fluid can fully be optimized.

 

[JTK]

Originally Posted By: Whitewolf
... I just happen to know about different ATF chemistries and what happens when you mix them.....you should NOT ideally mix ATFs unless you know the specifics of the chemistries involved.


I respect your knowledge.

I'm having a hard time grasping why big players like Valvoline and Pennzoil would assume the risk of marketing 'mulit-vehicle' ATF like the ones listed, if they spell certain disaster if you mix them with other ATFs.

I'm sure they're slightly different formulations, given they're different companies, but I'm also pretty certain they're formulated to not destroy a transmission if mixed with other merc/dex name brands.

Joel

 

[Letter_K]

Originally Posted By: Whitewolf

With the advent of DEXRON-VI and other specialised fluids mixing at random is not to be advised. It may be that if you are not stressing the transmission too much you can get away with it but it is not the ideal.


I'm here to learn, so please explain. Doesn't GM control the Dex VI additives (IIRC wasn't there one manufacter) and the base oil need to meet GM requirements to gain GM licensing? So Dex VI wouldn't have much difference, except if you're talking Maxlife and other product that meet specs, but aren't licensed by GM?

Or are are you talking in general about all new improved fluids that exist today. Also a curiosity, Whitewolf are you this industry?