I was planning to get the XL-12 transfer case fluid and now see that Mercon LV is now approved for all transfer cases. Does it matter which one I get? 2016 F-250 6.2 4X4

 

I put the transfer case fluid in mine when I changed mine going by what my manual says. I think either fluid would be fine.

 

The manual has been superseded. Mercon LV is now the correct fluid.

 

Is this supersession in writing?

Are you able to provide a link to a current Ford or Motorcraft document or website that establishes that Mercon LV is the appropriate service fill for Ford truck transfer cases?

Here is the current (as of April 18, 2019) Motorcraft Chemicals and Lubricants product information page concerning transmission and transfer case lubricants:

https://www.motorcraft.com/us/en_us/...on-fluids.html

And here is a screen shot (taken April 18, 2019) of the link referenced above, scrolled down to the Mercon LV description and application:

 

Both of the below screenshots were also taken on 4/18/19. Don't you just love it when two different arms of Ford have contradictory information?

https://www.fcsdchemicalsandlubrican...ission%20Fluid

says



And

https://www.fcsdchemicalsandlubrican...ission%20Fluid

says

 

I'm sure part of Ford's business model is selling new parts to people who blew up their transmission or transfer case because they cannot understand Ford's Byzantine fluid system.

What a crock. I'll bet Peugeot and Renault have less confusion in their fluid lineup. Did Ford put high school interns in charge of this?

 

Somebody posted here on the forums that they went to their local Ford dealer to purchase XL-12 and was told it was discontinued and Mercon LV was the replacement fluid for the transfer case.

 

I found a place online that still had XL-12 and ordered enough fluid to do two changes(I change every 20-25K)so I'll have enough to get me by for the rest fo the time I'll own my current truck.

 

XL-12 was nothing special. Just Mercon add pack in a Synthetic base oil. This can easily be replaced with Valvoline Transfercase Fluid, MTL fluid or use what Ford now uses which is LV. I will say the BW are much more tolerant of a thinner fluid unlike the older NV units.

 

So, looking at the screen shots, I am now more confused as ever. So I guess LV is ok? The manual to my 2015 says XL-12, which is still available from Rock auto. Was that the factory fill?

 

That was me....I was advised by the local Ford dealer (in Canada) that XL-12 is no longer available and is superseded by the Mercon LV....which is what I used in my transfer case...but mine is a 2012.

 

So I guess I should be looking into Mercon LV for my 2010 transfer case? I did find some XL-12 on FleaBay and it's pretty pricey.

 

XL-12 was the factory fill. If you can still get it there is no reason not to use it, otherwise LV is what Ford uses now.

It's kind of like the oil spec. Up until a couple years ago 5w20 was what the 6.2 called for then Ford switched to 5w30, either will work but I continue to use the old spec.

 

My "opinion" is that either would be satisfactory. Either Ford has determined that LV has a performance or durability advantage or they're simply streamlining their logistics systems.

Take it for it's value ($.02 or less).

 

What if Ford switched to 5W-30 because after 6 or 7 model years of field data aggregated from hundreds of thousands of 6.2L engines produced during those initial years, it was found that 5W-20 didn't quite have enough durability in real world usage?

What if Ford switched to 5W-30 a couple of years ago because Ford tweaked the tuning and "modified the camshafts to bump up the torque to 430 ft lbs" for the 2017 model year?

How do you know if, when Ford changed the oil spec, Ford intended the new oil spec to apply retroactively, or not?

The only way I would know is if I wrote Ford a letter, providing my VIN, and asked Ford. And even then, the only way I'd really know is if Ford wrote back.