Some driveline oil questions

[Jeffksf B]

So getting ready to do rear diff, front diff, transfer case, and Tranny oil changes.



First the owners manual says the AWD transfer case takes Ford Transfer case fluid, I'm used to Ford transfer cases taking Mercon tranny fluid, what is everyone using?



Second, how can I find out if the I have a Limited slip rear end? Need to know if I should add the LS additive to the gear oil.



TIA Jeff

 

[Yardsale]

Look on the sticker that is located towards the bottom on your drivers door. You will find a AXL code. This code will tell you the axle ratio and differential type in your st.



41 - 3.27 non-limited slip (Explorer/Mountaineer)

45 - 3.55 non-limited slip (Explorer/Mountaineer)

46 - 3.73 non-limited slip (Explorer/Mountaineer)

42 - 4.10 non-limited slip (Explorer/Mountaineer)

D1 - 3.27 limited slip (Explorer/Mountaineer)

D4 - 3.73 limited slip (Explorer/Mountaineer)

D2 - 4.10 limited slip (Explorer/Mountaineer)

 

[Vic Sorlie]

Thanks Yardsale. I too have an '08 STA (2wd); my axle code is 45. Jeff, I sent you the fluid lookup results. Contact me if you'd like to talk AMSOIL.

 

[Jeffksf B]

Thanks yardsale

45 here, 3.55, no wonder this thing is so lazy

 

[Yardsale]

Tire size change?



I had the 3.73 limited slip with the OEM 275-75/15, but changed to 4.10 after a trial period when I went to 265-65/17. Big difference.

 

[Jeffksf B]

No tire change, stock 20"



Vic, I didn't see what you sent me, email I assume?

 

[Johnny O]

I have a Gen 2 also and have used Mobil 1 ATF, Redline D4, and most recently Valvoline Synpower Transfer Case Fluid in the t-case. I change every 30k.

You do not have a LS rear. No Gen 2's have a LS, they have traction control instead. Rear diff takes 75w-140 synthetic, the front takes 75w-90 synthetic. The rear has a drain plug on the cover and is easy to change yourself if you get a transfer pump or suction gun to fill it and take the spare tire out. There is a hole in the frame in the spare tire well that you can snake the hose through to fill it. The front is basically impossible to do yourself because the front crossmember is very close to the diff cover and there is no drain plug (Gen 1's have the same problem) so I just take mine to the Valvoline Quicky Lube where they do it with an electric suction pump. I have tried draining mine with my suction gun and I can tell you that it won't work. The $50 that Valvoline charges is worth it when I consider the time it would take to do it myself and then the cover would probably leak anyway. I change the rear every 30k and the front every 50k. I have a Member Project posted here on how to change the t-case lube.

 

[Jeffksf B]

Thanks Johnny O

Just the info I needed. I gotta get my rear pinion seal as well that is leaking slowly so I will do that at the same time.

 

[Todd Z]

No gen 2 factory gets limited slip additive, None came that way. It does get synthetic in the diffs, and the v8 gets T-case lubricant.



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