We have about four thousand miles on our oil and we are halfway through our crosscountry trip. Should I change the oil soon? Can it wait until I get home? Thanks.

Syn oil? If so probably no problem. Not super science but a bit of old school crude paper chromatography analysis, put a drop on a flattened paper towel and let it sit for several hours to wick out several inches. If it is nearly uniform in color from center to edge the detergent is still doing its job and all is "probably" okay. There will be a darker spot where you put the drip. A drip from the stick will suffice. When the detergent fails it generally indicates breakdown of the anti-oxidant. WWYPFI
Tim

I routinely run 8K to 10K miles between changes, been doing this for 250K miles. Using regular oils. Diesels engine oil change intervals do not have to be as often as gasoline engines.

I use chevron because the bus company that does my maintenance uses it for their fleet.

Oil is under very little stress when the engine is at temp and running under load.

Modern additives and ULSD make the oil pretty robust. I do prefer Mobil Delvac, Shell Rotella T, or Kendall Super D.

Rusty, do you prefer Shell Rotella T to Mobil 1 for a gasoline engine?


Jim

I use Mobil 1 or Kendall synthetic in gaso engines, because they're formulated for them.

quote:

Originally posted by Rusty:
... Shell Rotella T...

Rusty, I know you say synthetic is a waste of money. Shell Rotella T6 costs less than $20. per gallon with the rebates and store incentives. I have been using Shell Rotella T6 synthetic in my Caterpillar 3208 for over 5 years now. I use T6 in every liquid cooled engine I own. I have used T6 since it first came out several years ago. Our member here, Tom K suggest changing oil every 200 hours in the 3208 Cat.

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If I recall correctly, Rusty said "oil is easier to replace than metal."

quote:

Originally posted by Rusty:
Oil is under very little stress when the engine is at temp and running under load.

Modern additives and ULSD make the oil pretty robust. I do prefer Mobil Delvac, Shell Rotella T, or Kendall Super D.

I will continue to run Mobil Delvac. I buy in the 5 gallon pails and change every year. With the rebate I get it for $5 a gallon.

DBarth took 15 quarts so less than 4 gallons. I am sure my Monarch with the 8.3 will take more.

Modern engines with roller cams use modern oils. Unfortunately the modern oils do not have the EP additives they used in the past.
Older engines with flat tappet cams need those EP additives to control cam wear. I used Rotella in my old 454 for that reason. The new 454 I installed has a roller cam so I use synthetic 10W-30.