by geeves » Fri Sep 11, 2015 10:44 am
Modern engine oils have friction modifiers that are great for bearings and rings but they coat synchro rings making then nice and slippery which isnt what you want.
I saw an advertising display that quoted Total as having the best friction modifiers.
3 options for gearboxes
Isuzu quote same grade oil as engine But use the cheapest oil you can find The $10 special will work better than the $60 synthetic
ATF is excelent option but can cause leaks
Several cos make oil for 5 speed boxes Dont worry about the fact that it says 70/90 or similar. They are gl4 oils and use a different viscosity scale
Sanding your knuckles before starting work can help. That way you cant skin them