Posted by Gary on May 27, 1999 at 06:34:40:
In Reply to: Hypoid or just Gear Lube posted by Steve on May 27, 1999 at 04:51:38:
Hypoid gears are gears that mesh in approximately a right
angle but so that the axes do not intersect (as they would
in a perfect right angle).
I believe that this causes a scraping action as the teeth
pass over each other and this necessitates a special sticky
kind of lubricant.
The 80/90 is, as I understand it, an 80 weight which contains
synthetic additives to hold the viscosity like 90 when hot.
There have been several postings about multi-grade vs. single
grade vs. synthetic oils. It's almost as hot a topic as Ford vs.
Dodge. There are all sorts of opinions.
What I am wondering is how often a rear end fails because of the
type of lubricant as opposed to the more obvious reasons.
It is also my understanding that the weights for these lubricants are
should be halved if you want to compare to motor oil. That is, (if I am
right about this) that 90 weight is like 45 weight motor oil.