rear diff fluid question

[Rob McClure]

hey yall,

my 1500 has the 3.21 rear gears ( i know ,lol ) without limited slip , I talked to ram to verify that it didn't have limited slip and they confirmed and the y sent me the build sheet which is pretty cool , my question is , I have Amsoil 75w/140 fluid am I good to run that in the diff ?

 

[hemihustlin]

if you already have that in stock go for it

i think they call for 75 90 in the 3.21 and 75 140 in the 392s so you will be good for max tow rating of your gears haha
dont forget the transfer case if you have one!

 

[Rob McClure]

awesome , thanks , ill just use it , lol ....AND do my front t-case , lol !!

 

[Wild one]

awesome , thanks , ill just use it , lol ....AND do my front t-case , lol !!

Hopefully you mean front diff,as you don't want to use diff fluid in your transfer case,it takes a totally differant fluid

 

[Rob McClure]

LOL ! yes I know the front t-case uses different fluid

 

[Wild one]

LOL ! yes I know the front t-case uses different fluid View attachment 585758

Little tidbit for you,it's "not" a front transfer case,it's a front diff.The transfer case is behind the transmission and is bolted to the back of the transmission in a Ram 1500. You'd be farther ahead learning to call it the front diff,as that's what it is,saves a $h!tload of misunderstanding when you ask questions. You didn't call the rear diff a transfer case,so don't call the front diff a transfer case either
Smartass answer or not,i could care less,but lets keep it correct and simple to save on mistaken answers Rob

 

[EdGs]

I too have a 2015 with open diff 3.21 and 75W-140 is what mine called for. Used Valvoline twice, no issues

 

[hemihustlin]

in reality gear oil is alot like motor oil, you chose viscosity according to intended/actual usage.
the guy thats towing all the time, extreme hot/cold or at the drag strip et cetra has different requirements than the average grocery getter in an "optimal" climate

even more important is regular maintenance. many people never change their gear oil so may the strongest pinion bearing win!!!