Transfer Case fluid replace

[fordysenior]

Hello, I'm wondering what is the proper fluid to drain and replace the transfer case fluid. It still has the factory fluid. But there seems to be controversy over what to use. The owners manual says Mercon ATF -- Some say use Mercon LV -- some say to use Motorcraft Transfer Case Fluid. The owners manual could easily be outdated, and the dealers haven't been very helpful. One parts store said to use Mercon V --and it takes 12.7 quarts. ok

 

[C420sailor]

Do not use V

Not sure what your case uses, but Ford has stated that V is explicitly not to be used in transfer cases due to case failures

 

[mountaineer2004]

The AWD transfer case in my Mountaineer takes Mercon (not Mercon V). I know Ford no longer licenses it but aftermarket companies still make it.
PS--don't overtighten the plug on the TC, as the TC is aluminum and will split open easier than you realize.

 

[fordysenior]

From what I've read, the AWD gets treated differently than the 4wd -- meaning it uses a different product. I think it's due to clutches in the AWD (I don't know, I've never worked on one). And I am aware of not over tightening the bolts.

 

[TechGuru]

OR

https://www.autozone.com/motor-oil-and-transmission-fluid/transfer-case-fluid/p/valvoline-transfer-case-fluid-1-quart/548658_0_0

https://www.autozone.com/motor-oil-and-transmission-fluid/transmission-fluid/p/valvoline-recommended-for-use-where-dexron-iii-or-a-mercon-fluid-is-specified-1-quart/516918_0_0

https://www.walmart.com/ip/Valvoline-DEX-MERC-Automatic-Transmission-Fluid-ATF-1-GA/15125788

https://www.autozone.com/motor-oil-and-transmission-fluid/transmission-fluid/p/castrol-transmax-domestic-dex-merc-automatic-transmission-fluid-1-quart/232570_0_0

 

[fordysenior]

This is what I'm finding on the net. Speaking of "Transfer Case Fluid". And this is why I think the owners manual is outdated. And same with the Haynes manual. BUT, even the net site may be outdated. I'm assuming the Mercon LV is the right oil for the transfer case?

"Ford has replaced it with Mercon LV. *XL-12 Transfer Case Fluid has been discontinued by Motorcraft® and replaced by Mercon LV. As of May 2019 an old Motorcraft web page still listed Mercon LV as Not For Use in Transfer Cases, but the most recent LV page specifically states LV is now for all transfer cases.
Until mid-2018, Ford specified synthetic base Motorcraft XL-12 Transfer Case Fluid for use in chain drive transfer cases that originally used Dexron II or Mercon, however, since that time Ford has superseded XL-12 with Mercon LV."

 

[Mbrooks420]

If you’re worried about it just get a Dextron/Mercon compatible fluid. That’s what came from Ford in the cases.

Same fluid in AWD, and 4wd. The 4wd actually has the clutches, and not the AWD.

 

[TechGuru]

This is what I'm finding on the net. Speaking of "Transfer Case Fluid". And this is why I think the owners manual is outdated. And same with the Haynes manual. BUT, even the net site may be outdated. I'm assuming the Mercon LV is the right oil for the transfer case?

"Ford has replaced it with Mercon LV. *XL-12 Transfer Case Fluid has been discontinued by Motorcraft® and replaced by Mercon LV. As of May 2019 an old Motorcraft web page still listed Mercon LV as Not For Use in Transfer Cases, but the most recent LV page specifically states LV is now for all transfer cases.
Until mid-2018, Ford specified synthetic base Motorcraft XL-12 Transfer Case Fluid for use in chain drive transfer cases that originally used Dexron II or Mercon, however, since that time Ford has superseded XL-12 with Mercon LV."

NO! Mercon LV is Mercon V and will kill the transfer case.

Use only plain Mercon or the Transfer Case Fluid I posted already.

 

[icepickjazz]

According to FordTechMakuloco, Motorcraft Mercon LV (Ford Approved in ALL Transfer Cases Now) for 4WD, not AWD. https://amzn.to/2yDpkUO
See his video
for details

 

[TechGuru]

The AWD transfer case in my Mountaineer takes Mercon (not Mercon V). I know Ford no longer licenses it but aftermarket companies still make it.
PS--don't overtighten the plug on the TC, as the TC is aluminum and will split open easier than you realize.

Ya both Valvoline and Castrol make a good "Dex/Merc"

 

[fordysenior]

Transfer case fluid is Mercon V -- and the literature says nothing about using it in transfer cases. The literature does say not to use V where LV is recommended.
https://www.motorcraft.com/us/en_us.../transmission-fluid/transfer-case-fluids.html

Mercon LV says it is for use in all transfer cases.
https://www.motorcraft.com/us/en_us.../mercon-lv-automatic-transmission-fluids.html

icepickjazz -- the video you linked shows to use Transfer Case fluid. If I go to YouTube and see the video, then in comments below the video, he shows that the Mercon LV is now acceptable for all transfer cases. It's too bad he doesn't put a disclaimer across the video where he shows the Transfer Case fluid.

 

[TechGuru]

Transfer case fluid is Mercon V -- and the literature says nothing about using it in transfer cases. The literature does say not to use V where LV is recommended.
https://www.motorcraft.com/us/en_us.../transmission-fluid/transfer-case-fluids.html

Mercon LV says it is for use in all transfer cases.
https://www.motorcraft.com/us/en_us.../mercon-lv-automatic-transmission-fluids.html

icepickjazz -- the video you linked shows to use Transfer Case fluid. If I go to YouTube and see the video, then in comments below the video, he shows that the Mercon LV is now acceptable for all transfer cases. It's too bad he doesn't put a disclaimer across the video where he shows the Transfer Case fluid.

I prefer to stick to using what was used when the vehicle was built to maintain the factory warranty at the time. Why would Ford care if you f*** up a out of warranty vehicle using some "new and improved" fluid? They may even want you to so you'll junk it and buy a new vehicle. Companies are just that malicious these days. You can't trust them.

If we were specifically told NOT to use Mercon V in the transfer case then one should not be using Mercon LV in it either.

Same concept goes for the transmission, I would stick with Mercon V for the transmission and not use Mercon LV.