Im looking to replace the TC fluid and have seen more and more posts warning against useing Mercon V, and to use Mercon LV, so I went to my local Ford dealer and asked for TC fluid. They simply gave me Mercon V ATF fluid and insisted its good to go in the TC. No where on the bottle does it say on the bottle that you can or cannot use it in TC.

 

 

The third bullet point on the back of mercon v bottle says:

”do not use in transfer cases”

 

If they gave it to you at the dealer I'd use it. I put maxlife synthetic atf in mine and it hasn't blown up yet.
in one of fordtechmakuloco later videos on changing the transfer case fluid he links to mercon lv as the product to use, so I'm thinking it doesn't matter that much. If it's wet and red it's probably good. Just don't use fruit punch.

 

I suggest spending a little more time researching.

I don't know when they quit spec'ing ATV for transfer case fluid.
I ordered up some for the 2016 pickup I have -parts counter quickly looked it up and told me the old spec is no longer available. As it turns out, my t-case is stamped with LV use only. Granted a different year, point is that the parts counter lady knew the old spec was not used, looked it up as a confirmation and sold me LV.

It's a good question that a seasoned mechanic with Ford's should be able to answer. I think the Ford service dept' calls the parts counter for fluids (at my location). Maybe walk in to the service department to ask what they pour in.

Note: when you do get around to draining, it's highly recommended to loosen the fill plug, just to make sure it can be removed. Sucks to drain the fluid THEN realize you can't refill it.

 

You’d use the wrong fluid, just because some guy at dealer hands it to you ???

LV is not V. Fordtechmakeuloco says that using V will make your transfer case “go boom”. I already provided the link to the video below.

Additionally it says right on the back of bottles that V is not to be used in transfer cases.

Go ahead and use what you want, but the info you provided and recommended to the OP is not accurate.





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For at least 3 years now we've been hearing that Mercon V in a T-case will cause disruption of the space/time continuum. Does anybody know the actual "Why?" behind this? I'd love to know the reason behind this, and I don't doubt there is one, but I've yet to find a soul who knows it.

 

I don’t ‘know’, but since LV stands for low viscosity, I would assume there is at least a viscosity difference. But given:

- LV is recommended
- LV costs less (although not much less)
- V specifically states not for use in transfer case

i don’t know why there is any real good reason to consider trying V in your transfer case.

 

If you do some looking into it you'll hear the word "Explode" used repeatedly. I want to know if it's a vapor volatility issue or something similar. Did XL12 get dropped in favor of LV? When this whole thing started XL12 was the go-to fluid. I haven't followed along for a while since I have the TOD transfer case. It has always called for LV.

 

Thanks everyone for the replies, on recommendation from another community I've order Valvoline transfer case fluid which states conformity to Ford XL-12 and Dex/Merc fluid requirements. Hard to find in my area paid extra but I think its a great choice.