Rear gear lube question... (car)

shady · May 16, 2012

I have a 98 town car that I'm using as a "long haul cruiser/ GF's DD". the rear end has a little seepage going on (wet on bottom of cover). So I'd like to replace the gasket and lube.

Hears the question.....

My car calls for 80-90w. But I was wondering if I'd have an issue running mobil 1 full synthetic 75-140W?

My thinking was I live in a colder climate than say Georgia. so the 75 part should help there. And I intend on a LOT of long runs in the heat of summer all over the country. So I figured the 140 part would be Ideal for that.

Am I thinking correctly? or should I stay with the 80-90w in Mobil 1 synthetic and be done with it?

dhcomp · May 16, 2012

shady said:
I have a 98 town car that I'm using as a "long haul cruiser/ GF's DD". the rear end has a little seepage going on (wet on bottom of cover). So I'd like to replace the gasket and lube.

Hears the question.....

My car calls for 80-90w. But I was wondering if I'd have an issue running mobil 1 full synthetic 75-140W?

My thinking was I live in a colder climate than say Georgia. so the 75 part should help there. And I intend on a LOT of long runs in the heat of summer all over the country. So I figured the 140 part would be Ideal for that.

Am I thinking correctly? or should I stay with the 80-90w in Mobil 1 synthetic and be done with it?

would probably be fine with either, but really...why change what they spec'd?

Just run 80-90w mobil 1, and be done. Remember, 95% of vehicles probably never have their rear end fluid changed....so you're doing it a huge service just putting new fluid in. :haha: