Light Diesel Engine Lubrication 1

[Nobrac]

I have been changing the lubrication oil and filter in my 1999 7.3liter International Powerstroke diesel (Ford f-250) at intervals of between 2,500 and 3,00 miles. I operate at 7,800 to 9,000 feet and with substantial loads on long grades. The truck is often overloaded; e.g. bumper trailer hitch could use a roller skate to keep from scoring the pavement. The oil change frequency is my uneducated effort at extending engine life for as long as possible.

My question: I have been advised that these oil changes intervals are way too frequent and that I am actually harming the engine by such practice. What say you who know?

 

[Fabrico]

About 85 of the 2,000 or so vehicles belonging to the company I work for, have Powerstrokes. Some tow and many do a lot of stop and go service. Not too much cold weather, but plenty of hot. About 90% of them are 1995 vintage and approaching 200,000 miles. Except for one that got stolen, crashed into a fence, turned on its side and abandoned while still running, none have had major engine problems. The oil change interval has always been 5,000 miles. Judging by our record so far, I would say we could stretch the oil changes to 6-6.5K miles without a problem.

Other than wearing out some threads and wasting a little money, I don't see how more frequent oil changes can hurt anything.

 

[Nobrac]

Thanks for the assurance. That was my pov too but this "expert" insists that I am doing more harm than good. I cannot imagine how but then I am not a diesel expert.

 

[patprimmer]

Changing oil to frequently does absolutely no harm to the engine. It simply wastes money and finite resources and creates extra waste for disposal.

Regards

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[Majik]

if you've got powerstrokes aproaching 200k on them you must be doing something right. powerstroke engines and rebuild kits are our bread and butter right now down in florida. changing it early shouldn't hurt anything. if fabrico's co has them rocking on at 5k intervals then I'd go with that.

 

[SMOKEY44211]

There may be something to the argument suggesting that too frequent intervals is detrimental. I did a study by taking oil samples at 1,000 mi. intervals (diesel fueled engine) and found that the greatest amount of particulate accumulation occured during the first 1,000 mi. After that it was a almost a straight line when plotted out on a graph. As a practice I fill the oil filter in applications where the filter is installed vertically thus reducing the amount of time that the engine runs with no oil pressure. This seems to have a benificial effect. In the test vehicles I found that the oil was still of acceptable quality till at least 18,000 mi. and one went as high as 24,000. There were several variables that couldn't be controlled or recorded such as climate, start up to drive warm up interval, and time left running when not driving the vehicle. Testing was done using a petroleum based oil not synthetic or reformulated. Based on tese findings I would say 7,500 mi. is a very conservative interval, with somewhere between 12,000 and 15,000 being the most economical. Most of the major manufacturers offer oil anylisis service at a very reasonable price so it might be worth investigating in your application.--------Phil

 

[drwebb]

Are you keeping an eye on the transmission fluid in those conditions? What's the OEM recommended service interval for that?

 

[Nobrac]

Good question Dr.Webb. the rest of the powertrain is often overlooked in the quest for engine life. All of our trucks ar manual trannys and change the tranny, transfer cases and both differntials ataround 15,000 miles.

BTW, all of our waste oil is reused for other purposes. This is a farming operation in the southwest and conditions are usully dusty or muddy. Waste oil is used for saturating new wooden fence posts (no more creosote)and oil buring furnaces. If we had a recylcing source that was within a reasonable distance; i.e. less than sisty miles, we would recylce it.

Smokey, that was an interesting study and duly noted. I, too, prefill vertical oil filters on all equipment and reduce the crankcase quantity by same amount for the very reasons you mentioned and documented. If you don't mind I am going to quote your study.

Thank you one and all.

 

[drwebb]

Someone in F1 once described the ideal equipment durability as when the entire car fails right after crossing the finish line. Only then would you know that you had extracted the full potential from a car that was not limited by over- or underdesign for the purpose. A bit drastic, but there is a point to be made there for all vehicle owners . . .