2.5CRD manual 6,500km with a noise lifting the clutch in neutral when warmed up. It mostly goes away when the clutch is right out, called 'Oh that's gearbox rollover mate, they all do that to some degree, bring it in hot and we'll have a listen'.
Just in case it was low oil level that didn't get checked on the 1,500km I took the level plug out and the level was perfect but the stuff dribbling out was less than impressive. Like warm dirty piss with a similar consistancy.
Decided to change it myself as the easier option and found almost 5L of Castrol EPX 80W/90 manual gearbox oil GL5, must have had it for 10 years.
The owners manual calls for 75W/90 hypoid GL4 as the closest brew to the Castrol.
It's in, lovely and thick compared with the crap that was in there and it shifts fine, perhaps a bit tighter on 2nd and selecting reverse. I haven't driven it to get it hot enough to check for the rollover noise but it's good to know it's got some decent oil in there.
Bottom line is, does anyone think it will cause problems, not so much the 80W instead of 75W but the GL5 instead of GL4 or GL3?
Right, GL5 contains higher sulpher levels for extreme pressure protection but is corrosive to brass and copper which may be present in the syncro rings? I'll ring Castrol on Monday and change it straight away if they say it's incompatible for that or any other reason.