mopar synthetic gear lube 75w-140 in axles ok?

N2BRK · 07-09-2009, 03:55 PM

I don't see any reason why not, but I thought I'd ask.

I have a line on 5 quarts dirt cheap and was thinking about buying them for my upcoming differential fluid change.

**Racerngr1** · 07-09-2009, 07:22 PM

75-140 is a pretty thick fluid, maybe if you are doing alot of heavy towing in high heat then go to the 140. I run the 75-110 Severe Gear in my truck and I tow back and forth to Havasu alot in the summer when it's 110* out and it seems to work really well with the 75-90 Severe Gear in front. Let me know if I can set you up with the Amsoil.

Heath · 07-09-2009, 07:25 PM

It'll work if the price is right. Not many run the 140, but nothing says you can't.

**Racerngr1** · 07-09-2009, 11:35 PM

It's not that it won't work, but there are other things that will work better in his truck. 75-140 is very thick and in turn will decrease his mpg's a little. Will it work, yes.

**bigdaddydiesel** · 07-10-2009, 12:56 AM

If that is what you want to run then you will be fine with it....

N2BRK · 07-10-2009, 09:11 AM

good info guys - thanks.

I did some looking and realize now that the OEM fill of 75w-90 is synthetic. I thought it was conventional, and 75w-140 in a synthetic would be just fine. I'm thinking now that living in NJ it gets cold enough for me to stick with a synthetic 75w-90 and not the thicker offerings; besides the fact that I rarely tow any serious weight.

RedBowTies88 · 07-10-2009, 09:24 AM

Quote:

Originally Posted by Heath

It'll work if the price is right. Not many run the 140, but nothing says you can't.

i ran 75w-140 full synthetic. and just recently bew a rear anyone think it contributed??? i always thought that was the best to run cause all the full synthetics that were at the store were that weight. I'll be an SOB if that's what just cost me 900

RedBowTies88 · 07-10-2009, 09:25 AM

blew up***

N2BRK · 07-10-2009, 06:53 PM

no way. If anything it gave you longer life, IMHO. I decided against since I do a lot of short commuting in the cold with mine (daily driver and 5mi commute to work). Even so, it's prolly still fine for me to use. Synthetics rely on surface tension and not viscosity, and I think either weight would have enough of a film on the surfaces to work just fine. The 75w-90 might give a slight advantage in short trips on cold days to flow a little better a little sooner, but the 75w-140 would give better protection when you're beating on it

**bigdaddydiesel** · 07-10-2009, 07:10 PM

I doubt very seriously if the lube in your rear actually caused it to blow up.