Originally Posted by oldhp
I would like to see a test with sensors showing by-pass mode time on a oil filter that goes 20K miles. Common sense says the filter would load up as used, and would go into by-pass more often.
Guess what?
They DON'T (when the oil is changed regularly)
I ran a Motorcraft FL-1A in the 1990's for 30,000 miles with regular oil changes,
and a Fram Tough Guard for 15,000 miles (2X oil changes at 7500) and it looked like brand new inside.
I recently ran a Fram Tough Guard for 50,000 miles (5x or 6x oil changes) and i haven't cut it open yet, but i guarantee you now it will look fine.
Originally Posted by TTK
According to my HS Chemistry teacher, Mr. Gilbert, oil never wears out and all you have to do is change the filter. That is all he did on his 1956 6 cylinder chevy straight drive car,
His oil filter was not a full-flow design.
Apples to bananas comparison.