Amsoil rear dif fluid question

[Rob McClure]

Hi ! Probably a dumb question , I'm about to change out my rear diff and get amsoil 75/140 do I need to add some friction modifier or not ? I know the severe gear has some friction modifiers in it just wondering if it's the right amount ? And do I just need two bags of fluid or should I get 3 ? Thanks

 

[Redfisher1974]

Im sure it has modifier in it, get 3 bags. You’ll have enough left over to only need 2 bags next time.

 

[joesstripclub]

I believe this is what I changed the rear diff with in my truck last time. I actually had to add a bit of friction modifier as I was getting a bit of chatter on sharp slow corners. My maintenance sheet says 4.4 pt plus 5 oz FM so you would need 3 quarts.

 

[crash68]

You can use Redline 75W-140 synthetic gear lube, it has the correct amount of friction modifier. Lots of members use it on the forum with no issues.
I bought a gallon jug and a pump that screws right onto the jug.
Be sure it's the 75W-140 and not the one with the NS on the lablel

 

[MRFREEZE57]

You can use Redline 75W-140 synthetic gear lube, it has the correct amount of friction modifier. Lots of members use it on the forum with no issues.
I bought a gallon jug and a pump that screws right onto the jug.
Be sure it's the 75W-140 and not the one with the NS on the lablel

This is what I used in my truck, did not need any additive.

 

[Redfisher1974]

I use RP 75-140 no additives needed

 

[Rob McClure]

for the redline gear oil, im running 37x12.5x17 inch tires does that matter or should I get the severe gear amsoil ? thanks for all the help guys .

 

[Gero]

I'm using the redline 75w140 and have changed it twice so far. But I'm probably going to go amsoil severe gear 75w140 because of the bag. Such a clever idea.