OVERKILL
$100 Site Donor 2021
Originally Posted By: 440Magnum
Originally Posted By: Merkava_4
Originally Posted By: cchase
Unfortunately 2 data points with no comparison to other viscosities is rather meaningless. I also think you're putting too much stock in "wear metal" readings in a single pass $20 UOA and trying to make a connection to increased wear.
I've seen some fantastic UOA's, but none of them have been with 20 weight
oils. Some of the best UOA's I've seen have been BMW's with 40 weights.
Then you just haven't looked enough. There are plenty of stellar UOAs with 5w20 and 0w20 oils in the UOA section. And there are some horrendous ones with 40-weight oils, too.
I'm not a big fan of going thinner than recommended, unless the engine has been back-spec'd to a thin oil. Thin-oil engines ususally have a lot of oil pump capacity, a large oil FLOW volume, and sometimes even depend on the low viscosity of the oil to make things like timing chain sprayers work correctly. Too *thick* of an oil in those engines may in fact do more harm than good, IMO. After watching an accurate (mechanical) oil pressure gauge on my Dodge 4.7, running 0w20 in the 113-degree heat while towing a travel trailer at 70 mph last summer, I'd *never* put a thick oil in that engine. The 0w20 hot idle oil pressure *never* wavered from how it behaves just driving around town un-loaded. That engine, like the Ford Modulars, is obviously very well-tailored to a 20-wt oil.
He is also forgetting that in many BMW's, like my S62, they have alumasil blocks. So since he's basing this "evidence" on UOA's (which is a horrible idea to begin with), and those engines have very little iron in them, he's going to see his desired low iron readings. And of course nobody runs a 20-weight oil in those engines (most run 40's) so he has subsequently created the ultimate strawman.
Originally Posted By: Merkava_4
Originally Posted By: cchase
Unfortunately 2 data points with no comparison to other viscosities is rather meaningless. I also think you're putting too much stock in "wear metal" readings in a single pass $20 UOA and trying to make a connection to increased wear.
I've seen some fantastic UOA's, but none of them have been with 20 weight
oils. Some of the best UOA's I've seen have been BMW's with 40 weights.
Then you just haven't looked enough. There are plenty of stellar UOAs with 5w20 and 0w20 oils in the UOA section. And there are some horrendous ones with 40-weight oils, too.
I'm not a big fan of going thinner than recommended, unless the engine has been back-spec'd to a thin oil. Thin-oil engines ususally have a lot of oil pump capacity, a large oil FLOW volume, and sometimes even depend on the low viscosity of the oil to make things like timing chain sprayers work correctly. Too *thick* of an oil in those engines may in fact do more harm than good, IMO. After watching an accurate (mechanical) oil pressure gauge on my Dodge 4.7, running 0w20 in the 113-degree heat while towing a travel trailer at 70 mph last summer, I'd *never* put a thick oil in that engine. The 0w20 hot idle oil pressure *never* wavered from how it behaves just driving around town un-loaded. That engine, like the Ford Modulars, is obviously very well-tailored to a 20-wt oil.
He is also forgetting that in many BMW's, like my S62, they have alumasil blocks. So since he's basing this "evidence" on UOA's (which is a horrible idea to begin with), and those engines have very little iron in them, he's going to see his desired low iron readings. And of course nobody runs a 20-weight oil in those engines (most run 40's) so he has subsequently created the ultimate strawman.