UOAs from 1990 or even earlier?

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I have read that a lot of the problem with engine wear in earlier generations was that the oil wasn't protecting the engine properly in the first minute of operation, but that thinner grades now are doing a much better job at startup.

Has anyone seen UOAs of engines from 1990 or before, that presumably would have much higher levels of wear metals, than those with modern oils? I know that seeing a dozen from before that time would be a hopelessly small sample, but still, it would be nice.
 
Thin oil is all about CAFE. The thin oils do help as the temperatures drop to freezing and below. The time it takes for the oil to flow from the oil sump to the oil pump is important.
 
Originally Posted By: CT8
Thin oil is all about CAFE. The thin oils do help as the temperatures drop to freezing and below. The time it takes for the oil to flow from the oil sump to the oil pump is important.


At one point yes corporate average fuel economy was why thinner grades were specified because automakers had to pay based on these numbers.
Today it's not quite that simple. Thinner oils do have some advantages and in an engine that doesn't experience high oil temps there's no reason not to use it(depending on clearances). They dissipate heat better. Use less fuel during warm up which not only helps cafe numbers but can save the owner money. The engine experiences less drag which means more power to the wheel. It's not a lot but it's something.
The pentastar has a 2 speed oil pump. So at high rpm it swtiches gears reducing oil volume/pressure helping power to the wheel as well.
So for engines designed with a 20 grade in mind there is no penalty in using them. Older engines or higher output harder working engines still need something thicker because oil temps can get very high,thinning the oil to the point it can equal a 20 grade.
So yes in the beginning it was CAFE. Today it's not so simple. And let's be serious here,who doesn't want to use less fuel knowing its cost monetarily and to our environment.
 
No it all about cafe and emissions plain and simple. Meeting the long emission warranties is simply amazing to how the engine building has changed.
 
Originally Posted By: CT8
No it all about cafe and emissions plain and simple. Meeting the long emission warranties is simply amazing to how the engine building has changed.


Smarten up.


For example. An accord and a Camry. If one uses thicker oil and mileage is less people buy the accord.
The market is dictating the fuel economy now anD the primary driver,CAFE doesn't matter. If a vehicle doesn't sell what does it matter.

Why does anyone even talk to you. You are so bullheaded you can't see the forest for the trees.
Believe what you want. I couldn't care less.
Evolve or go extinct. You'd be smart to remember that.
 
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Sorry that I spent my life working in the industry and been through factory training classes emissions and Cafe push. Rather that thinking I know. I have been there. Point you finger at me and there are more pointing to you. I guess I am not a carpenter ans a week end racer.
 
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