5w40 vs 5w30 for 3.5 HO?

ROBERT BONNER

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Interesting thread. After reading through it, I have a couple of comments.

Relative to fuels used by the manufacturers, it's complicated. EPA certification is done with extremely expensive and difficult to obtain EPA certified "standard" fuels, those standards change over time and I'm unsure what the formulation and Octane levels are today; but, suffice it to say it is fuel either with or without certain "additives" that isn't readily available to the general public. Back in the day (still?) it came out of a single U.S. refinery in traceable lots. This was done to ensure that all vehicles were EPA certified on exactly the same fuel. That being said, there is a genuine attempt by manufacturers to ensure that fuel systems and engines are compatible with popularly available fuels. The fuzzy area always has been that the EPA holds manufacturers accountable for emissions regardless of fuel formulation....BUT THERE IS NO ATTEMPT TO CERTIFY OR EVEN CHECK THAT STANDARDS ARE MET WITH ANYTHING OTHER THAN THE CERTIFIED FUEL. Manufacturers make their own standards relative to performance or durability associated with certain fuels (read alcohol type and level) True story: in the early 2000's when E85 was becoming popular and the government was handing out Fuel Economy credits for "flex fuel" vehicles that could handle E85, Ford had a durability spec that stated that all flex fuel vehicles (regardless of fuel tank capacity) had to be able to burn (3) consecutive tanks of E85 without experiencing a fuel related failure...it wasn't easy. Popularly available fuel pumps weren't reliable enough; so, ford installed fuel pumps that would live, at a significant cost ~$100/vehicle. The durability people pointed out that GM and Chrysler were selling flex fuel vehicles with standard fuel pumps at a $100/vehicle cost savings.....and that their trucks with high capacity fuel tanks couldn't handle one single full tank of E85 without fuel pump failures....The proposal was for Ford to revert to standard pumps because "no customers" were burning E85 other than in a few select midwestern states and we would upgrade their failed pumps with better pumps after failure under warranty - which is what GM and Chrysler were reportedly doing. We didn't make the change and eventually all vehicles had to be upgraded as the use of alcohol increased.

Motor oils: One of the most important things mentioned above was the question about any typical or unique engine failures due to motor oil choices. And none of us can think of any. I believe that what you're buying with frequent changes of high quality proper viscosity oils and filters is longer long term durability and maybe performance. I have only anecdotal proof of that. It would be interesting to run stats on it; but, bottom line is no one really cares to know enough to run the survey's and stats to understand the relationship. One thing is for sure with these compressed motors: Blowby and increased contamination/dilution of oil is a simple fact with these motors compared with uncompressed motors. When you run an extra atmosphere over the rings before the compression stroke, you're going to blow more fuel, carbon, combustion gases, etc. past the rings than with a naturally aspirated motor. The question is what to do about it. Separators are probably a good idea. I don't have one; but, I've been looking. The next thing is to change the oil and that silly little filter more frequently. I put fresh M1 and M1 filters on every 5K even though the computer says I could go twice as long....If nothing else, it makes me feel better, lol.
 

LokiWolf

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Interesting thread. After reading through it, I have a couple of comments.

Relative to fuels used by the manufacturers, it's complicated. EPA certification is done with extremely expensive and difficult to obtain EPA certified "standard" fuels, those standards change over time and I'm unsure what the formulation and Octane levels are today; but, suffice it to say it is fuel either with or without certain "additives" that isn't readily available to the general public. Back in the day (still?) it came out of a single U.S. refinery in traceable lots. This was done to ensure that all vehicles were EPA certified on exactly the same fuel. That being said, there is a genuine attempt by manufacturers to ensure that fuel systems and engines are compatible with popularly available fuels. The fuzzy area always has been that the EPA holds manufacturers accountable for emissions regardless of fuel formulation....BUT THERE IS NO ATTEMPT TO CERTIFY OR EVEN CHECK THAT STANDARDS ARE MET WITH ANYTHING OTHER THAN THE CERTIFIED FUEL. Manufacturers make their own standards relative to performance or durability associated with certain fuels (read alcohol type and level) True story: in the early 2000's when E85 was becoming popular and the government was handing out Fuel Economy credits for "flex fuel" vehicles that could handle E85, Ford had a durability spec that stated that all flex fuel vehicles (regardless of fuel tank capacity) had to be able to burn (3) consecutive tanks of E85 without experiencing a fuel related failure...it wasn't easy. Popularly available fuel pumps weren't reliable enough; so, ford installed fuel pumps that would live, at a significant cost ~$100/vehicle. The durability people pointed out that GM and Chrysler were selling flex fuel vehicles with standard fuel pumps at a $100/vehicle cost savings.....and that their trucks with high capacity fuel tanks couldn't handle one single full tank of E85 without fuel pump failures....The proposal was for Ford to revert to standard pumps because "no customers" were burning E85 other than in a few select midwestern states and we would upgrade their failed pumps with better pumps after failure under warranty - which is what GM and Chrysler were reportedly doing. We didn't make the change and eventually all vehicles had to be upgraded as the use of alcohol increased.

Motor oils: One of the most important things mentioned above was the question about any typical or unique engine failures due to motor oil choices. And none of us can think of any. I believe that what you're buying with frequent changes of high quality proper viscosity oils and filters is longer long term durability and maybe performance. I have only anecdotal proof of that. It would be interesting to run stats on it; but, bottom line is no one really cares to know enough to run the survey's and stats to understand the relationship. One thing is for sure with these compressed motors: Blowby and increased contamination/dilution of oil is a simple fact with these motors compared with uncompressed motors. When you run an extra atmosphere over the rings before the compression stroke, you're going to blow more fuel, carbon, combustion gases, etc. past the rings than with a naturally aspirated motor. The question is what to do about it. Separators are probably a good idea. I don't have one; but, I've been looking. The next thing is to change the oil and that silly little filter more frequently. I put fresh M1 and M1 filters on every 5K even though the computer says I could go twice as long....If nothing else, it makes me feel better, lol.
Excellent points.

Yeah, those early E85 invoked pump failures are always used in the argument against E85. I can say for a fact they don't have that issue anymore, but man people bring it up, and the fuel lines not being compatible too. Annoys the crap out of me.

Based on the tuners I know who have had their tunes EPA certified in the past year, they say the standard fuel is CRAP. It was getting KR's and pulling timing. They said it was crap for getting power, but that didn't matter because all that mattered is that they passed the emissions test.
 
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