ATF fluid a340 dex merc 3

[LexusToyotanut]

My 2001 tundra transmission calls for dex merc 3… I used to buy Valvoline dex merc 3 from Walmart all the time and would do a lot of drain and fills. Well the blue valvoline bottle I used to buy that plainly stated “dex merc 3 “ is no longer available to buy.. now it just says “dex merc”. Is this stuff the same as the dex merc 3 stuff? Just a label change? And no, I don’t mean if it’s interchangeable, I want to know if it’s the same exact fluid but just a labeling change. I want the same fluid I have in there in it, more importantly I want the same fluid the engineers said to put into it. I don’t want a thinner synthetic Dexron 4 fluid in it, I want good ole stupid, thick, shear prone, old school dex merc 3 in it as my transmission will last 450k+. THANKS!!!!

 

[kschachn]

What is Dexron 4?

And a DEXRON-VI fluid is much more shear stable than a DEXRON-III fluid. It’s built into the license requirements. Why do you want more shear? That’s not a good thing.

One does not really know exact details about a supposed DEXRON-III fluid since there are no licensed fluids. Look around for several recent threads on this same topic.

 

[mattwithcats]

Looks the same to me…

US_Val_DEXMERC_ATF_EN.pdf - DocuSign CLM

sharena21.springcm.com

Valvoline Dex/Merc Automatic Transmission Fluid (ATF) 1 GA
https://www.walmart.com/ip/15125788

 

[someonesomewhere]

My 2001 tundra transmission calls for dex merc 3… I used to buy Valvoline dex merc 3 from Walmart all the time and would do a lot of drain and fills. Well the blue valvoline bottle I used to buy that plainly stated “dex merc 3 “ is no longer available to buy.. now it just says “dex merc”. Is this stuff the same as the dex merc 3 stuff? Just a label change? And no, I don’t mean if it’s interchangeable, I want to know if it’s the same exact fluid but just a labeling change. I want the same fluid I have in there in it, more importantly I want the same fluid the engineers said to put into it. I don’t want a thinner synthetic Dexron 4 fluid in it, I want good ole stupid, thick, shear prone, old school dex merc 3 in it as my transmission will last 450k+. THANKS!!!!

I needed a quart for my PS flush. I found AC Delco Dex3 was the cheapest I could find that wasn't a generic or a 'one size fits all' multi fluid. Was $5.25 at the time, looks like it's $6.99 currently. Checked all my boxes, being as it's GM GM atf. Lol. Probably might have chosen something cheaper if I needed more than under a quart for my PS fill though. Got it from Amazon.

ACDelco Gold 10-9240 Type III (H) Automatic Transmission Fluid - 1 qt, 32 Fl Oz (Pack of 1) https://a.co/d/7KqWWpP

 

[LexusToyotanut]

What is Dexron 4?

And a DEXRON-VI fluid is much more shear stable than a DEXRON-III fluid. It’s built into the license requirements. Why do you want more shear? That’s not a good thing.

One does not really know exact details about a supposed DEXRON-III fluid since there are no licensed fluids. Look around for several recent threads on this same topic.

Like I said I don’t care about how shear prone old dex 3 fluid is, because I want the exact old dinosaur fluid the Toyota engineers spec’d inside my transmission. Dex 3 is thicker than the newest additions to the dex merc line. I want that, not thinner new age fluid. My transmission should last 400k at least with dex 3

 

[LexusToyotanut]

Same as my power steering fluid, I don’t want a thinner newer dex fluid, I want the old thick Dyno dex merc 3 fluid in my power steering system

 

[wlk]

RockAuto has a 5-gallon pail of Mag1 Dex3 for $69 plus $15 to ship to my house. After taxes and shipping, it was $85.27, and at $17.20/gallon can't really beat that if you want Dex3

 

[Graham Piccinini]

Like I said I don’t care about how shear prone old dex 3 fluid is, because I want the exact old dinosaur fluid the Toyota engineers spec’d inside my transmission. Dex 3 is thicker than the newest additions to the dex merc line. I want that, not thinner new age fluid. My transmission should last 400k at least with dex 3

This is the best, and somewhat widely available DEX III fluid. Old-school thick stuff, yet with benefits of a full synthetic. Click HERE to buy.

 

[kschachn]

Like I said I don’t care about how shear prone old dex 3 fluid is, because I want the exact old dinosaur fluid the Toyota engineers spec’d inside my transmission. Dex 3 is thicker than the newest additions to the dex merc line. I want that, not thinner new age fluid. My transmission should last 400k at least with dex 3

But DEXRON-VI is thicker. Or will be in a short time. It’s not “new age” it’s better in every way.

 

[kschachn]

This is the best, and somewhat widely available DEX III fluid. Old-school thick stuff, yet with benefits of a full synthetic. Click HERE to buy.
View attachment 199713

What’s the shear stability of that particular product?

 

[Graham Piccinini]

What’s the shear stability of that particular product?

Mobil 1 claims it to be "Exceptional". They also make the following claim: "Mobil 1™ Synthetic ATF outperforms conventional ATFs and helps to provide outstanding resistance to oil breakdown and deposits." Unfortunately no numbers were provided to throw around. But over the years I have seen many testimonials here on BITOG, as well as other forums, and met people in real life who used that product. All point to the same results and conclusion that this fluid holds up very well, even in heavy duty applications, despite the initial sheardown that so many Mobil fluids experience. I do recall claims that the initial sheardown is done on purpose (per Mobil apparently), but I do not plan to spend the rest of my day searching for those claims and official confirmations now.

 

[kschachn]

The shear was not “on purpose” it was permitted by the terms of the license. There was no requirement for a certain amount only a limit.

 

[Dehaka]

i am of the same mind set..... If you don't like what you find out.... I've been using Mobil D/M (dex merc) in 4 vehicles that take dex 3 or mercon. very happy with it.

I would assume its the same. Dexron 3 and mercon are the same thing essentially. And thats the application that valvoline dex merc is intended for.

 

[JHZR2]

We’re running generic Walmart D/M, half high mileage, half regular, with a dose of Lubeguard red, in my brothers FJZ80, which I think has the same AT. No issues or concerns.

 

[proveitwithdata]

The shear was not “on purpose” it was permitted by the terms of the license. There was no requirement for a certain amount only a limit.

As a consumer, besides feel good marketing, what does the synthetic in Mobil 1 or Valvo Import Atf signify? In addition is their gray area in what constitutes "synthetic" as it does for say american synthetic motor oils?

My assumption was it will be shear resistant, but I have my doubts now.

 

[RedSpider]

The A340's of this era will work well on just about any fluid you throw in there.... generic Dex/Merc, Dev VI, Mercon V, T-IV, WS, whatever.... I've used them all in mine and the thing just keeps going and going. The downfall of this model trans is the pre-'03 versions with the undersized torrington bearing that butts up against the 4th gear planetary, when that disassembles itself it takes everything with it. Just dont tow in overdrive, do periodic drain/fills with whatever Dex/Merc you can find and you'll be fine, this transmission is not picky at all when it comes to fluids.

 

[kschachn]

As a consumer, besides feel good marketing, what does the synthetic in Mobil 1 or Valvo Import Atf signify? In addition is their gray area in what constitutes "synthetic" as it does for say american synthetic motor oils?

My assumption was it will be shear resistant, but I have my doubts now.

The base oils are synthesized. Trying to make this into yet another "what is a real synthetic" won't be of much help.

Oh and it's not "American" in any way. Group III synthetic oils were sold worldwide before they were marketed in the US. They still are. Lots of hyped up misconceptions on that subject.