mobil full syn. multi vehicle or mobil dex 6

[tig1]

Originally Posted By: hardheaded
i was just looking for the best trans fluid for the car. i'm torn between the two.


I have used M1 ATF for at least 20-25 years and have never had a trans or PS pump failure. Some vehicles with 350K. At present I use it in my Fords and both trans shift like new, up and down. I drain the pan every 30 K and change the filter every 60K.

 

[LeakySeals]

Originally Posted By: mrdctaylor
Having recommended M1 ATF like I did (and I stick by this recommendation), I can also say that I've used Dex VI in an older (2002) Chevy transmission and it has worked just fine. It has been about 2.5 years and maybe 10K miles. All is still well.


Here's a sheet I made recently trying to find the right transfer case fluid for my truck. I used ACDelco Dex III and VI #'s as a guide. My transfer case shuddered on Maxlife, and now I know why. Its the thinnest on the list. Nowhere near Dex III compatible.

https://docs.google.com/spreadsheets/d/1PUme9oKKBiteasuwokfE7s4dNN5CjcKb-h1OFjbHIrk/edit?usp=sharing

 

[kschachn]

Originally Posted By: hardheaded
after reading all this i had my son who works at a local chevy dealer ask some of the techs there what the recommend. they all said to use the dex VI. don't know what i'll end up putting in there. i'm leaning towards the mobil syn.


That is the correct answer. Dexron-VI is backwards specified for Dexron-III applications.

It has been noted on here multiple times that Dexron-VI fluids are specified to be more viscosity stable than the previous Dexron-III fluids, so even if the Dex III starts out at a higher viscosity there is no guarantee it will stay there.

 

[hardheaded]

i shot Mobil an e-mail and now who ever anwser it is saying to use Dex VI. sounds like it depends on who you ask on which to use, even Mobil keeps going back and forth. i thnik i'll just go with the DexVI as my son can get it at cost though the dealership. hope i don't regret it.

 

[4WD]

The Mobil 1 ATF VI is way up there - but other than M1 fluid I would do Dex VI for the money ...

Dex VI from AC Delco gets oxidized (looking) in my Cruze - so trying Castrol synthetic multi right now ...

 

[CKN]

Originally Posted By: kschachn
Originally Posted By: MaximaGuy
Common sense dictates that older vehicles WILL NOT be tested with newer fluids PERIOD no matter what these bottles claim.
Having said that all new vehicles always come with ever changing newer fluid specs.

Stick with MaxLife D3 and call it a day


You've made that comment twice now with no technical support whatsoever. You have no basis for your claim.

Besides, do you know what the major difference is between Dexron III and Dexron VI? From your repeated unsubstantiated comments I don't think you do.



Yep-the fluid manufacturer here is going to go on this forum (where old cars hang out) or some old car club to try some new fluids. Ain't gonna happen. I agree with Maxima guy-common sense dictates there are no trials in old cars with newer fluids. It's a "real life" trial.


It certainly doesn't take long for threads to deteriorate on BITOG anymore.

 

[Garak]

We have had formulators here comment about the shear stability of the newer fluids. The times when the older vehicles have real problems is when the seal material is so radically different than what we use now that we have difficulties. Note that even the older style fluids aren't necessarily what was being used back in the day.

Back specs with more modern formulations happen all the time. Formulations also change without notice.

 

[69GTX]

The DEX VI or Max Life ATF with approx 5.8-6.0 viscosities may be more shear stable, but they sure as heck aren't starting out life in the 7.0-7.5 range of the DEX 3's. Considering that M1 ATF (see UOA above) sheared down from 7.4 to 5.7 over 30,000 miles, it must have spent half its life in the 6.5 to 7.4 range....far better than those LV ATF fluids. I'd stick with a quality DEX 3....whether M1 ATF, RedLine D4, Amsoil ATF, Honda ATF, or similar product where the add packs are quite stout. The Castrol Transmax's at 7 or greater are ok. The conventional ATF's tend to have some fairly weak add packs. The Valvoline D3 add pack is on the weak side. I wouldn't use the Max Life Dex 3 with a low starting vis of 5.91....that doesn't meet the visc spec of Dex 3 even if PQIA accepted it as ok.

I'd be ok with a shear stable ATF that started out in the 6.5-6.8 range....but not 5.8-6.0. Too far from original DEX 3 specs.