Neither. I change my oil and filter in ALL my vehicles every 5,000 miles. Much easier to keep track of with a simple glance at the odometer (5,000/10,000/15,000/etc).Brian said:The manual says your first should be at 7500 for normal use and 3750 for severe use. How many people follow the severe route and change their oil every 3750 instead of 7500?
This is an "old wives tale", or as close as you get in the automotive world.pjb3 said:MG Pilot
Oil may be better than in the past but modern engines put a greater demand on the oil also.
I would disagree. All of your points deal with contamination which I agree have been reduced. What about oxidation of the base stock and depletion of additives? Many modern engines have DOHC with increased bearing surfaces, tighter tolerances, higher operating temperatures, and higher specific output increasing loads on bearings.N_Jay said:
This is an "old wives tale", or as close as you get in the automotive world.
Modern engines are much easier on oil, it is the oil that has changed little in the past 30 years.
1) Less Blow-by, less combustion contamination
2) Leaner burning, less fuel dilution
3) Better materials and machining, Less contamination from wear products
4) Better temperature control, less excessive heating of the oil
5) Sealed crankcase, less moisture contamination
6) Lead free gas, less heavy metal contamination
N_Jay said:
1) Less Blow-by, less combustion contamination
2) Leaner burning, less fuel dilution
3) Better materials and machining, Less contamination from wear products
4) Better temperature control, less excessive heating of the oil
5) Sealed crankcase, less moisture contamination
6) Lead free gas, less heavy metal contamination
OK, OK, you got me. Not sealed completly, but well sealed, and typically using intake manafold vacume to maintain a slight negative pressure.AlH said:
Name one engine, with a sealed crankcase.![]()
Perhaps you meant that they are no longer vented to the atmosphere, but they aren't sealed. .