Oil Change Intervals

We would like to know what facts or fictions u used to come to this conclusion. And oil should never have to absorb dirt.

 

That would be true if one on the surface. Soot, silicon (dirt), and other particulates are measured as a ratio in an oil sample. If soot isn't building up, then oil is not "saturated". For instance, I use a bypass filter on my '06 ISX and others may use one or one of the centrifuge units. My soot levels consistently average between .1 ppm and .3 ppm after 25,000 to 30,000 miles. Silicon is consistently at < 1 ppm. And TBN (additive package) levels are well within normal limits. No matter how you look at it, that is clean oil by anyone's standards and still good.

Lunacy? I guess it depends. Your statement doesn't sound well reasoned. Oil doesn't get "saturated" but in fact is a carrier of contaminants which are measured as a percentage. Many here, like myself, have been monitoring engine oil performance in everything from small to large diesels in construction equipment, ag equipment, and trucks for several decades. I think that you would have a bit of an issue proving that these folks and myself know nothing about engines.

It would be lunacy to just extend the oil drains without having an understanding of oil samples and what to look for. Just relying on the hype put out on brochures by filter companies and such is not realistic. But sampling done by a reputable lab is the only sound way to go.

If one doesn't choose to extend their oil drains, so what? No skin off my back. I don't try to set world records in extending my drains, but I use a little common sense and rely on actual data to make an informed decision that extending my drains 2 to 3 times the OEM suggested level is realistic and not harming my engine. And the facts speak for themselves.... 1.4 million on my previous N-14 without ever being opened up except for running overhead, still averaged over 7 mpg and only used about 1 gallon each 8-10 thousand miles. It got 30,000 mile oil changes on Kendall oil with baldwin filters for its entire life. My present ISX has 630,000 miles on it and using a bypass filter, wear metal levels consistently lower than similar engines with lower miles, and soot levels that are impressive for an EGR engine. Had the oil pan off recently to replace a leaking gasket. Nice clean pan with no residue, crank/rod bearings looked clean and good. Overhead done late last year and top side was clean with not buildup. No worries.

 

The whole idea of testing oil to judge the soot buildup in the engine is pretty naive and serves mostly laboratories. All they check is the oil, not the engine... Sludge buildup is whole different story, but takes more effort to find out since you have to open the engine more or less.

I don't blame you nor anyone for being cheap or even selling BS products - it's all good as it floats your boat, all I'm saying, its dumb to save few bucks on oil only to be charged thousands for earlier rebuilt.

 

Your exactly correct. it is just the way I've always done it. when I first started trucking oil changes were sooo much cheaper. since I have had such great luck I thought I just need to keep doing what I'm doing. I am afraid as soon as I do something different, like go to 15,000 miles on oil changes, I will regret it & something bad will happen because of it. I would love to go 14-15,000 miles. I guess I change my oil like I change my tires. I dont wait until they are just at d.o.t. spec's, but before. I may try going longer, since now my inframe is broke in & I do not idle. appreciate the insight on this topic.