yeehaw
New member
I have always used 75w140 synthetic in newer Ford rear ends, but looking on Mitchel on demand, it's telling me to use 75w90 in my dually. Is this correct? I wanna service it pretty quick here, it's lookin pretty black.
servicing rear end fluid
- Thread starter yeehaw
- Start date
03international
New member
in for this one. i havent serviced mine but would like to know what to use.
Tag on rearend. Held.captive by a bolt shank.
Rear is usually 75w140. Front 75w90. I use the 75w140 in both. No problems. I dont think.it would.matter in my case because I.change it every two years. Unless I put huge.miles on, then sooner.
Ive used tons consequently, oddly enough royal purple gear oil is good yet their motor oils are poop. I had bad luck with amsoil syn diff fluid. Mobil 1 or rp are the two Id pick. I used to use.redline in stuff.but never.in a hd.truck. It specifies "syn" for both my diffs,fyi.
Rear is usually 75w140. Front 75w90. I use the 75w140 in both. No problems. I dont think.it would.matter in my case because I.change it every two years. Unless I put huge.miles on, then sooner.
Ive used tons consequently, oddly enough royal purple gear oil is good yet their motor oils are poop. I had bad luck with amsoil syn diff fluid. Mobil 1 or rp are the two Id pick. I used to use.redline in stuff.but never.in a hd.truck. It specifies "syn" for both my diffs,fyi.
91turbogsx
Active member
It's 75w140 for the Sterling 10.5's. 75w90 for the Dana 80.
greenthunder7.3
New member
are you supposed to put the slip modifier in the dana 80's like you are the sterlings? i put it in my sterling 10.5 on my 99 f-350 srw when i changed the fluid but was j/w if it also to be used in the duallys.
91turbogsx
Active member
If it has a limited slip then yes. Just pay attention to the gear oil you choose because some already have an additive in them as well.
Yea, rp does. And it works well,imo. No clunking of clutches. Works good. Im unsure if Mobil1 does.
yeehaw
New member
i used valvoline, has additive in it as well, sometimes it doesnt hurt to add some equa torque too but depends on the vehicle it seems
lincolnlocker
Well-known member
please do tell why?
exactly what i have in my dually... been taking some major abuse too... love it
