I have been sorting through old threads for about an hour and have not answered all my questions.

1. Do the front and rear diffs use a different weight of fluid? ( I don't have an owner's manual to refer to)

2. I keep seeing differing opinions of using rtv OR a gasket or BOTH? Whats the concensus on the guys?

Thanks for your help.

 

Yes per owners manual 75w-90 in the front diff, and 75w-140 in the rear diff. I used valvoline full syn on mine (it already has the additive in it) When you pull yours apart you will see an orange residue that is rvt form a gasket scrapeit off good and replace with eithyer red blue or black really doesn't matter btw. enjoy and post pix when done

 

depends on the truck 1500 or 2500

i called 2 dodge dealers to find out and both came back the same .....
1500 ram front 75w-90
rear 75w-90 ..unless you tow allot use 75w-140

2500 ram front and back 75w-140

the 1500 youneed RVT
the 2500 you re use the gasket .

 

asuming the 1500 , use the 90 in front and 140 in the a$$ these diff's are tempermental as it is. imo.

 

for a 1500 yes i agree

for mine i tow ect , and wit no c-clips to worry about im good .

 

And totm winner too boot, rh.

 

2x ...dont forget that lol

 

Now go post on my jacked up thread!@! lol

 

They sell gaskets for the 1500 diffs, but if you apply the RTV correctly it is actually more reliable than a gasket.
Your choice though.

As far as the fluid goes, if you do not tow or haul a lot, then you can just buy 75/90 for both. I don't tow often but on occasion have pulled a 7500# tractor on a big dual axle trailer. Couple that with the fact that I have to run a conventional oil in the rear according to the gospel of St. Auburn, I run a 85/140 Lucas Heavy Duty conventional oil. I run a 75/90 synthetic in the front...

 

Never knew that .rtv is what i di but I could see myself picking up a gasket just in case. Napa, autozone one of those places i imagine.?