Ok so those familiar with this engine know Ford narrowed the oil passages on the VCT's and roller rockers to supposedly increase flow to other parts of the engine. At the same time, the consensus is to go to 5W30 on this engine, particularly if you've needed timing and/or valvetrain parts.
My curiosity is, is 5W30 the best choice given the smaller passages, particularly in the rockers? The holes in the rockers are I'd say half the size of the original design. If 5w20 was spec'd for the original parts, albeit the engine had oil flow problems BUT that was blamed on weak oil pump and tensioners, then shouldn't one stick with 5w20 especially with the new smaller passage VCT's and rockers?
Now I know there are plenty of guys out there with 300k on engines they claim to have run 40 and 50 oils in, and also those with high miles claimed to have run on a 20 so I know of the cases for either way. I just wonder what ya'll think.
My curiosity is, is 5W30 the best choice given the smaller passages, particularly in the rockers? The holes in the rockers are I'd say half the size of the original design. If 5w20 was spec'd for the original parts, albeit the engine had oil flow problems BUT that was blamed on weak oil pump and tensioners, then shouldn't one stick with 5w20 especially with the new smaller passage VCT's and rockers?
Now I know there are plenty of guys out there with 300k on engines they claim to have run 40 and 50 oils in, and also those with high miles claimed to have run on a 20 so I know of the cases for either way. I just wonder what ya'll think.