well I run pure synthetic, ive seen much better results from it and it also can go longer, im in colder climate northern Canada so in winter I find even in -40 I never had issue with tranny(synthetic) or engine starting not plugged in. now if I can only get it to heat the cab... changed front and rear and T case for synthetic so I believe in it..

if it askes for 10/30 then it was designed for that .. so it will be fine