What viscosity?

[elbo989]

I'm changing the fluid in my front and rear end, along with the Manual trans and T-case. I have no idea where to begin with the viscosities. Any help would be appreciated.

[elbo989]

[TANK'S 250]

I have lockers in both of my axles...mine is an 05 F-250 PSD

I use Valvoline SYN Power(full Syn) 75-140 in the axles, and Mobil 1 Synthetic ATF Mercon V in my manual tranny.

[elbo989]

Thanks. Also, I thought you were supposed to use a heavy weight oil like 80-90 or something not ATF?

[TANK'S 250]

nope....manual tranny in my truck calls for Automatic Tranny Fluid