I never said any of that. I said things like ideal bearing clearance gaps today aren't any tighter than they were many years ago. Production tolerances, meaning variation from ideal, has gotten better but that's largely a different topic.
People keep saying "tighter tolerances" but they clearly don't understand the definition of the term.
We aren't talking about your 2009 Ram, we're talking about a Toyota Tundra. Toyota gives no similar warning about using heavier oil, and you might note that even Chrysler doesn't say it's going to damage the engine.
I responded to this posting of yours:
"Originally Posted by GManBart View Post
Further, the whole "tight tolerances" thing is largely hogwash."
Speaks for itself.
Then there's this you posted:
"We aren't talking about your 2009 Ram, we're talking about a Toyota Tundra. Toyota gives no similar warning about using heavier oil, and you might note that even Chrysler doesn't say it's going to damage the engine."
Agree RAM says:
"My 2009 Ram Hemi P/U's owner's manual specifically said that the oil pump in the engine was designed for 5W-20 and that if you used a heavier oil it could impede the ability of the engine to do the cylinder drop economy function."
Yes that's not admitting to damage but to potential non-functioning of a benefit of current engine technology which is in high demand when fuel prices skyrocket like was the case back then, and could cause unnecessary, frivolous warranty claims.
However, it doesn't take a rocket scientist to figure that thin oil saves on wear and tear on initial startup which is advertised to be the #1 cause of engine wear....aka engine damage!
And this from you:
"People keep saying "tighter tolerances" but they clearly don't understand the definition of the term."
Scuse me? I think the difference between 0.001" and 0.0001" is easy enough for the average Joe/Jane to recognize as 10x tighter tolerancing.