RowJ

Problem - Oil gets black w/i 50 miles of changing it.
Solution - Simple Flush!
(I've never really thought it was a serious problem but many have questioned it on this site)

With todays tighter diesel engines, it never made sense to me that it is just "the nature of the beast" that new oil should get black soon after oil change .

I tried an experiment. I let the oil drain for about 1/2 hr...as always. Then I left the plug out and added 1 qt clean oil. What came out was dirty oil. Added a second qt clean oil. Half way through second qt...oil coming out was new and clean. Inserted plug and filled sump.

After 150 miles (130 on hwy at 70 mph)... oil on dip stick is clear! This includes one test run at the track.

Conclusion, Oil drain hole is not the lowest point in the pan. Well over 1 qt of old oil remains during an oil change. This 'flush' also seems to clean out the used oil left under the valve cover. Is this 'flush' needed or recommended? Certainly not critical.... just nice to know my engine is as clean as I thought it was.

Note: My Cummins has 135,000 miles on it.

RJ

1-2-3

Just get better oil filters. Try Geno's. Great place to get them. Stay as far away from Fram and other off the shelf Walmart/Autozone filters a you can get.

nickg

Just dumping new oil thru the valve cover, is not going to flush the left over old oil out, the old stuff hides in all the nooks and crannies, you would be better off, dumping in a can of engine flush, I perfer the Amsoil stuff. and use a good quality filter, there is a link on the web about the Amsoil Ea filter, actually making the oil cleaner AFTER it was run thru an engine! I'll try to find it.
FWIW mine goes about 500kms before going dark, I have 333,000Kms(around 200,000Miles I think), also by your sig, more fuel equals, dirtier oil quicker

RowJ

I have always used Fleetguard Stratopore.

RJ

RowJ

I assumed the same thing. But was amazed how clear my oil was after some hard miles??
Just reporting my findings.... for anyone interested.

RJ

yfz450guy

good findings at that. i often thought about doing an oil change and driving for a week then do another oil change. kinda like i do with the trans.

bnold

I was there after 150miles and when I read the dipstick I had to turn away or towards the sun to find the oil on the dipstick it was really that clean!! I'll be trying it on my next change... And I'm running Amsoil dual-bypass so I think my filtering is more than adequate... His oil was very impressive, curious to see how long it lasts!!

I found out the bung in the oil pan is not the lowest part and leaves a good amount of oil in the pan... Also there is a fair amount of oil left on top of the head after a normal drain.... Now I'm sure there is still probably and extra half to a full quart of oil oil left after the 'flush' in oil galleys, oil pump, whatever, but the 2 quarts of oil really cleaned out a lot of it.... I was really shocked I mean the oil was crystal clear

johnh

when these engines last so long without rebuilding, there is NO problem with black oil..... if my oil doesn't get black righ away, i get worried

dj_souvlaki

my oil is always clean. even after 5000 km it always looks fresh.

Valv

Last year I bought a '97 CTD with 197,000 miles as a project truck..
It had what I thought was a blown head gasket. When I removed valve covers all the components were in perfect clean shape. Same for pushrods, etc.
It blew my mind how such a high mile motor was so clean inside.
And all cylinders still had factory crosshatch.
All my trucks (5 so far) oil always has been clear to a point, even after 5000miles. I never seen real black contaminated lubricant since I had a Chevy 6.5l