Gearbox oil

[mabsydney]

I just replaced the oil in my gearbox with Castrol EPX 80W/90.

Shifting isn't that great. Any recomendations for a better oil that won't break the bank?

[rick130]

What box ?

[mabsydney]

R380

[rick130]

that treacle you have in there is waaay too heavy. Get it out pronto, before you wreck it. These gearboxes are pressure fed from an internal gear pump, there is a chance the EPX is too thick to flow quickly enough up through the oil galleries when cold.

The factory fill was Caltex MTF94, you can get it from a dealer reasonably.
Some people use Castrol VMX-80, but I reckon it shifts like crap, or use Castrol Syntrans or Redline MTL. Both these cost @ $25/litre. Redline can be obtained from Coventry Auto Parts around Sydney.

Red90 has a good site here showing suitable viscosity lubes.

[mabsydney]

thanx rick, much appreciated

[mabsydney]

thanx again Rick changed it out today, I put Dextron III as the synthetic stuff is too expensive and the LR workshop told me they use Dextron........changes are heaps better now.

[red90]

Using Castrol VMX80 or Redline MTL will be better for the box in the long run. They specified ATF because, at the time, there were not any low viscosity manual transmission lubes on the market.

[rick130]

as Red90 said, your gearbox, and hip pocket, will thank you in the long run if you use a GL4 gear lube as suggested.

VMX80 isn't very expensive, being a full mineral oil, and has the correct EP and anti-wear additives for better bearing and gear tooth protection over an ATF.

With the synthetics you can safely double the drain interval, making them a lot cheaper, + they give you better long term protection. EG, Syntrans is rated for 300 000km in ZF commercial 'boxes.
ATF is also a lot thinner than these gear lubes, and I've had Redline MTL and Castrol Syntrans thin out a little too much on 40*+ days.

[itsame]

i have been told by many of the queensland box rebuilders that they will not warrant their rebuilt boxes unless you use vmx80

[Philip A]

I asked the Castrol tech line what their recommendation is for an R380.
He said that VMX80 would be OK but that he would recommend Syntrans for its higher temperature stability for use in hot conditions.

Regards Philip A