Originally Posted By: LargeCarManX2
Fluid specs are just that,,,, specs.....
Redline 5W20 cST@100 = 8.58
Mobil 1 0W30 = 10.2
O'Reily Syn brand 5W20 = 9.9 and 5W30 = 11.0
Were not talking huge differences. If a fluid is close to 5W20 specs....go for it.
Although, I would use Redline 5W20 in that engine
Quoting the KV100 spec's (and btw they are all wrong) while ignoring the much more relevant HTHS vis' couldn't be more misleading.
Companies such as Chrysler, Ford, Toyota, Honda, etc that specify a 20wt oil are specifying an oil with a HTHS vis of 2.6cP.
RL 5W-20 is a very unique oil with a HTHS vis of 3.3cP which means it is actually heavier than most 30wt's.
M1 0W-30 has a HTHS vis' of 3.06cP which is fairly light for a 30wt but is still much heavier than any typical 5W-20 oil at all temp's above -20C.
The OP