Transfer Case and Differential Fluid

[Geargambler]

I know the procedures. I'm asking here about the fluid to be used.

I have a 2017 Expedition Limited.

Front differential - 80w90 with no friction modifier
Rear Differential - 75w 140 synthetic, with friction modifier 2.75 quarts (3).
Transfer Case - XL12 transfer case fluid. 2 quarts.


Let me know your thoughts on my notes here!

 

[Black]

I have a 2016 and my owners manual calls for 75w85 front and rear. Assume the 17 would be the same but one never knows with Ford.
I used Amsoil 75w90 Severe gear oil took just under 2 quarts before weeping out the fill hole.
Also used 4oz of Motorcraft Friction Modifier.

Also only use Motorcraft Transfercase fluid. No other multi-application fluids. They include detergents that can cause issues.

 

[Geargambler]

I have a 2016 and my owners manual calls for 75w85 front and rear. Assume the 17 would be the same but one never knows with Ford.
I used Amsoil 75w90 Severe gear oil took just under 2 quarts before weeping out the fill hole.
Also used 4oz of Motorcraft Friction Modifier.

Also only use Motorcraft Transfercase fluid. No other multi-application fluids. They include detergents that can cause issues.

Thank you for mentioning the transfer case fluid. I did read about that. The motorcraft stuff is pretty expensive ($40 per qt on amazon?). Valvoline makes a transfer case fluid that meets the XL12 spec that is WAY less expensive.
https://www.amazon.com/dp/B071VDQLVZ/ref=cm_sw_em_r_mt_dp_U_3wR.CbJ6CCVSZ

I have used redline 75w90 synthetic for multiple applications. Maybe I'll use that in the front. The front didnt call for friction modifier but the rear did.

 

[Black]

Thank you for mentioning the transfer case fluid. I did read about that. The motorcraft stuff is pretty expensive ($40 per qt on amazon?). Valvoline makes a transfer case fluid that meets the XL12 spec that is WAY less expensive.
https://www.amazon.com/dp/B071VDQLVZ/ref=cm_sw_em_r_mt_dp_U_3wR.CbJ6CCVSZ

I have used redline 75w90 synthetic for multiple applications. Maybe I'll use that in the front. The front didnt call for friction modifier but the rear did.

I don't believe the front differential utilizes a limited slip differential so there is no need for the Friction Modifier.

I was going to say get the transfer case fluid from your Ford dealer. I think it was like $15 a quart here.

But in some more reading I found something interesting.
according to this website the Transfer Case Fluid has been discontinued as of May 2019 (hence the reason they are wanting $40 a quart I would say) and it says that Ford is now calling for Mercon LV for transfer cases.
https://torqueking.com/product/737/1-quart-ford-motorcraft-xl-12-transfer-case-fluid/

I then googled the 2017 Owners manual and on page 308 of the manual it too lists Mercon LV as the fluid for the transfer case.
http://www.fordservicecontent.com/F...s-Manual-version-3_om_EN-US-EN-CA_12_2016.pdf

I'd be interested to see what your printed manual says.

 

[Geargambler]

From my printed owners manual, page 310.

Transfer case fluid, (US and Mexico)
Motorcraft transfer case fluid XT-10-QLVC
WSS-M2C938-A Mercon LV