Originally Posted by gcdidthis

use 5 w20 as directed on the CAP. the guys that built the motor intended it because of tolerances in the motor. there is fantastic article linked in here somewhere... i do believe there is high mileage 5w20 available. also, accept the fact you WILL burn oil and switching to heavier weight oil will not make it better...

at work we have 3 different generation fseries from 150 to 450 with different motors and without fail they require 5w20.

as for the posts, the regulars here find it easier to answer one question once. the search function can usually answer any question you can think of..