What gearbox oil + what Diff oil - modded minor

Post by **h_____** » Wed Mar 26, 2003 1:35 pm

Hi everyone,

let me have your opinions on what I should be using.

Gearbox - I have a 5spd Seirra box, due a change
Rear diff - Have a marina back axle and diff, it is very noisy!!

Car needs to be reliable, so happy to buy premium grade products to keep it going.

regards

H

Post by **h_____** » Wed Mar 26, 2003 1:36 pm

...and I have heard that slick 50 is good for noisy diffs, anyone had any experience?

Post by **Cam** » Wed Mar 26, 2003 1:56 pm

For the gearbox, use Castrol Syntrax

For the rear axle, use EP90 (Hypoid). (don't bother with Slick 50)

In both cases, fill up to the filler plug.

Post by **h_____** » Wed Mar 26, 2003 1:57 pm

Cam,

why not bother with Slick 50?

regards
h

Post by **Cam** » Wed Mar 26, 2003 2:01 pm

Heard reports from some people that it improves things, also heard that it does absolutely nothing!

A noisy diff (whining) is caused by worn crown wheels / pinions, so you will not be improving matters, just reducing the wear rate slightly (maybe).

In any case worn whiney diffs can last for a good while. It's the bearings you have to watch out for.

The Slick 50 is probably not worth the money for the improvement it will give.

Post by **rayofleamington** » Wed Mar 26, 2003 11:33 pm

Vehicle manufacturers spend countless millions trying to get good reliability etc..
If Oil-additives were that good, Vehicle manufacturers would use them for services - and they dont!

They may have a small effect to reduce surface frictions, but I don't know anyone who works in the automotive development industry that does use them other than for race engines.