Re: what grade oil for my 151c 4cyl
Yes, but only if it's a synthetic.
Non-synthetic 10W40 has the highest amount of VI improvers compared to the others (10w30, 5w20, etc)
For that reason FOMOCO said they would VOID the warranty if it was used in my 86 6.9L diesel. (the owners manual indicated that it "may cause engine damage")
In the 90's Consumer reports indicated that 10w40 should not be used because it didn't stay in grade as well as the others.
(
synthetic 0w40, 5w40, 10w40, 20w40 doesn't count since they don't use VI improvers [the entire oil is a "vi-improver"]......that's one of the advantages of using synthetic oil)
In fact, if you compare [SYN]0w30 and straight SAE 30, the viscosity at 100*C
IS THE SAME. That's where it counts! not at cold temps. ...........(does anyone boat in -30F weather where you would need a synthetic multigrade oil?..........wouldn't the block be frozen solid?.....
jeeze, wouldn't the whole frakken lake be frozen SOLID?
)
Now, having said all of the above, every oil known to Man (& Women
) has been used successfully.
Use whatever is on sale at Wallyworld. (I wouldn't use "Non-Syn" 10w40 in ANYTHING!
)
Cheers,
Rick
