quote:
Originally posted by Chris B.:
What do you think the minimun mileage should be for extended drains? Everyone seems to run there oil at different lengths. So what should be the bare minium mileage, 5,000, 7,000, more?
Depends on many factors.
But to keep it simple, I'd say anything 10-20% (15%) higher than the factory suggestion.
Most cars can safely go 4K, a well maintained car that is not worn can probably go 5-7K depending on "driving conditions" and filter changes.
I'd say to you if you are worried then don't.
This is what I'd do to put your mind at ease.
Nex oil change, Run several hevy dose of Fuel treatment through the tank, then follow up to about 2K with treatments each fill up.
Change ALL your filters (air, Gas, Oil), and change the oil. Go about 1000 MIles and change the filter, then go another 1500-2000 miles and change filter again. Then go about another 1500-2000 miles and again change the filter and oil &
Pull a sample!
This new batch, Change filter only at about 1500
then again around 3000, then another at 4500, then by this time you shall see the results of the first run. If they look good, go another 1500 and drain/sample, if they don't drain first chance and sample.
This is the third batch:
Go about 2000-2500 then filter change, then another 2000-2500 then filter change.... etceteras.
Sooner or later you can lay a finger on the trend, and where your engine wants to have it's oil changed.
If you are worried; then DONT. I have has several cars I pushed WAY WAY farther with no testing and they survived.... Going farther than you should IMO will not hurt if it's only a time or two, but with the method or one similar to the above should get you to the milage fairly safe...
The main thing is that you wan't to keep the filter clean, and you want to monitor the oil at some stage in its life, and gradually push the limits further and further until you can see a trend of when and where the oil begins to thicken or thin out more than say 5%