Whoops . . . I've Done It AGAIN!! Clean oil 2 days and counting!!! - PeachParts Mercedes-Benz Forum

EDBSO · #1 06-19-2011, 06:26 PM

Well it has been 62 days, 16,240km, 10,500 miles since my last oil and filter change. I normally don't let it go that long but I was relying on the Flexible Service System (FSS) and it was still showing 4,800km, 3,000 miles to my next service. I only added 1/2 of a quart during this period.

The good news is that 2 days after the change and the Rotella T6 5W40 is still clean. You may recall that I posted that my last oil change stayed clean on the dipstick for over 10 days.

I used the same drain procedures this time but I measured the extra oil that came out. I drained the oil normally and put the drain plug back in after the oil stopped dripping. I then using a large 3 ton jack raised the driver's side (North American drive) up as high as the jack would go. Both wheels were off the ground. After lowering I drained and measured the extra oil that came out and I got over 3/4 of a quart of oil that would normally be left in the engine.

I think this extra 3/4 of a quart of oil removed is the principal reason that the oil stays clean on the dipstick days after an oil change. Previous to this jacking routine my oil would be black as tar after driving to the end of the driveway.

I thought that the previous oil change might have been a fluke but now I am 100% certain that I am draining more dirty oil out of the engine that before. Refilling took all of 2 full gallons and leaves the oil level midway between full and add oil on the dip stick.

I am draining more oil out and adding more back. It is a bit of extra work but for me it is worth the effort.

Now where is the oil coming from? My belief is that it is oil left on the head that drains when tilted. It could also be that I am draining the oil cooler. Or it could be that I am doing a bit of each. I don't know but I do like the result and would encourage others to try the same.