Mobil-1 changed their ATF formula... - PeachParts Mercedes-Benz Forum

gsxr · #1 10-04-2007, 05:52 PM

I started a thread over in the Tech Help forum - here's the link:

http://www.peachparts.com/shopforum/showthread.php?t=201492

Basically, the new Mobil-1 "Multi-Vehicle Formula" ATF isn't Dexron approved, and Mobil recommends that GM cars up to 2005 requiring Dexron fluids use their Mobil Dexron VI (non-synthetic) fluid instead. The new M-1 MVF stuff says "Mercon" all over it. Our pre-2000 Mercedes typically need a Dexron III fluid.

Looks like I'll be switching to Amsoil in the future, unless I can find a few cases of the "old" M-1 ATF on clearance somewhere.

winmutt · #2 10-04-2007, 06:05 PM

BOOO I wonder why the change?

gatorblue92 · #3 10-04-2007, 06:45 PM

man thats a bummer... i just switched to mobil 1 a few months back too

DieselAddict · #4 10-04-2007, 07:10 PM

I recently did a change with this new fluid on my E300D. So far so good, and the performance is at least as good as it was with the old fluid, which I believe was the older Mobil1 ATF. Personally I'm not worried about this new ATF and the change might just be a labeling change. The new, post 2005 transmissions apparently require a thinner fluid which might not be the best choice for our older transmissions. I checked the specs on the fluid in question and they're virtually identical to those of Red Line D4. I'm not worried. BTW, I thought Dexron VI was a synthetic too as it wouldn't make much sense for GM to recommend a non-synthetic for "better performance".

gsxr · #5 10-04-2007, 07:22 PM

The wording from Mobil is somewhat contradictory, IMO. Dexron VI is not a full synthetic. They're marketing their Dex-6 as a "synthetic blend" ATF.

Anyway, the new MVF stuff may work ok. But besides their weasel-y wording on the new formula, it has a very distinct (unpleasant) odor that the old M-1 formula, and MB fluid, does not have. To me, that indicates a significant change in the formula. I haven't put any in my cars yet, and don't intend to. And I sure won't be recommending it to anyone in the Mercedes community anymore.

oldiesel · #6 10-04-2007, 07:35 PM

Most marine transmissions use Dexron,so i asked the supplier where i get parts about synthetic trans fluid,he said dont use it as no mfgr has approved it. I know these are not automotive transmissions but the clutches are very similar so i wonder,have any auto mfgrs approved it for use in their cars? Don

DieselAddict · #7 10-04-2007, 08:03 PM

It says it's approved for all Chrysler vehicles, Fords specifying Mercon and pre-2006 GM vehicles. I think that's good enough. I still had a bottle of the old ATF when I did the change and I didn't notice any difference in smell, though I didn't compare them closely. Even if this formulation is a step backward from the latest and greatest, which I'm not entirely convinced, I think it's probably still better than what was offered back when our cars were new. Dexron III is an ancient formula.

gsxr · #8 10-04-2007, 08:36 PM

Quote:

Originally Posted by DieselAddict

It says it's approved for all Chrysler vehicles, Fords specifying Mercon and pre-2006 GM vehicles. I think that's good enough.

Like I've said (repeatedly), the wording on their spec sheets is very odd. The new M-1 MVF is "approved" only for Mercon/Allison/ZF applications, not Dexron. It's "recommended" for Dexron apps, but they then "recommend" their synthetic blend Dexron VI formula for "improved performance" on pre-2006 GM vehicles! Why would a synthetic blend out-perform a full synthetic, and only for Dexron applications? Sounds fishy to me. Their Dexron VI formula is "approved" for Dexron applications. It's like they're saying "yeah, you can use M-1 MVF in Dexron transmissions, but we'd rather you didn't... instead, you should use our synthetic blend fluid." Oh, and also, the new MVF stuff is about 20% cheaper than the previous M-1 formula it replaces. That's also a little odd.

Quote:

Originally Posted by DieselAddict

I think it's probably still better than what was offered back when our cars were new. Dexron III is an ancient formula.

True. But there may be disadvantages to the new stuff that we're not yet aware of. I'd prefer not to find out the hard way!

pawoSD · #9 10-04-2007, 09:00 PM

I've had this "new" type of Mobil 1 Synthetic in my tranny for thousands of miles...and it runs exactly the same....my dad's SD has it as well....so I doubt it is any issue.

Ken300D · #10 10-05-2007, 08:18 AM

Are the new vs. old bottles visibly different? I'm with you, I really like the classic Mobile 1 ATF formula. I may have to go on a supply hunt too.

Ken300D

gsxr · #11 10-05-2007, 10:13 AM

Quote:

Originally Posted by Ken300D

Are the new vs. old bottles visibly different? I'm with you, I really like the classic Mobile 1 ATF formula. I may have to go on a supply hunt too.

I have a new and old bottle... I will try to take a photo of each (front & back) and post them. The new bottle is seriously lacking the word "Dexron" and mentioned "Mercon" frequently, which is what prompted me to go read their spec sheets carefully...

gsxr · #12 10-05-2007, 11:27 AM

Here's photos of the old & new bottles. Note that the old bottle says "Dexron" all over the place, while the new bottle only mentions Dexron for (1) telling you to use their semi-synthetic Dexron VI fluid instead of Mobil-1, and (2) for use in power steering systems.

Ken300D · #13 10-05-2007, 12:19 PM

Oh, I think my supply is already tainted because I remember the new "mod-squad" curvy bottle.

The two bottles reference different web sites for people seeking more information. I hope the latter one is not hosted in China......

Ken300D

patbob · #14 10-05-2007, 02:14 PM

Quote:

Originally Posted by gsxr

Sounds fishy to me. Their Dexron VI formula is "approved" for Dexron applications. It's like they're saying "yeah, you can use M-1 MVF in Dexron transmissions, but we'd rather you didn't... instead, you should use our synthetic blend fluid."

Sounds like a classic marketing vs. engineering/lawyers conflict. Marketing wants to claim its good for everything, engineering, with the help from the lawyers, slip into the fine print that it really isn't because they can't fix marketing so the company isn't liable when somone believes the marketing.

Anyone know what the difference between dexron and mercon specs are? Maybe there's a difference and it doesn't meet dexron specs anymore, but in a way our old cars won't care about?

pawoSD · #15 10-05-2007, 02:16 PM

We're switching over to the AMSOil Synthetic Transmission fluid, as it is both Dexron III and Mercedes Spec certified. Also, its pretty much the same price. So why not. We returned that nasty smelling MultiVehicle formula stuff...gross. We may even change engine oils over to AMSOil if it looks like its cheaper.