Outer Limits 4x4 Board

Need some advice on my gearbox in the Patrol. (TD42)

The 5th gear syncro is grinding when going into gear.
However this is only after the car has been driven for 30 - 40 minutes or more (ie when the oil heats up and thins out a bit). I have put the redline MT90 into it and it is still the same.

When its cold and before the 1/2 hr there is no dramas getting it into gear at all.

I have heard of another bloke using mobilfluid 424. It's a tractor gearbox oil and is very thick. Anybody else heard of or tried this as a solution.....

thomo.in.a.gq wrote:
I have heard of another bloke using mobilfluid 424. It's a tractor gearbox oil and is very thick. Anybody else heard of or tried this as a solution.....

I'd say the baulking ring on 5th is rooted ,no "snake oil" type fixes here time to pull it down & fix it properly .
we use 424 or donax td in all our transmissions from patrol to truck through to steiger tractor good oil but it's NOT thick, actually not much heavier than ATF.

i use atf in al my manual boxes as it helps the synchros

try running an 80w oil, your oil is definately getting way too thin at operating temp.

However days will still be numbered on 5th gear synchro. Its going to wear out sooner or later.