Intersting link here. [LINK]

 

That is interesting & I'm sure its true if a vehicle is not over abused, towing too heavy. The way we all monitor our trucks anyway we're probably fine at 5-6k between changes with dino. I think I'll try 6k this time & do a blackstone oa, see how it looks.

 

I read that article some time ago. That info coupled with all the oil analysis I have seen reported on this site convinced me to go to 10k intervals. I am at the end of my first 10k interval in the next month, and I will be sending a sample off for my first analysis on the X If it weren't for the leaky turbo pedestal, I wouldn't have even needed to add oil on this cycle. Oh well, that pedestal's days are numbered...EBPV and actuator are getting deleted at the end of the month!

 

oil sampling have a lot to do with my oil change intervals.run engine oil about 10k with mostly highway miles.and 7500 mix town & highway on quality synthetics ,should work your way up to extended oil changes to establish trends with samples.

 

A guy that I recently helped out, with some low power issues, performed the first oil change on this 03 at 147,000 miles fresh oil did not change sound or power. Needless to say I was amazed on an HEUI injected motor.

Now this was not with oil analysis, or any special filtering or treatment this was sheer neglect...

 

Good Lord!!!! On the issue, let's look at trucks that get worked hard and their oil change interval and oil capacity. The Cummins ISX15 liter engine holds about 10 gallons and Cummins recommends a normal oil change at 30,000 mile intervals with NON-SYNTHETIC OIL. We have 4 gallon capacity so that is about 40% of the oil capacity of the ISX15. Our engines are slightly less than 50% their size (in liters) and I am sure we don't work our engines nearly as hard as an over-the-road truck. So just using capacities and work load we should be able to go 40% of 30,000 miles or 12,000 mile change intervals. I remember a few issues back in Fleet Owner, Chevron claiming 50,000 mile change intervals for their Delo 400 15w-40. My 2 liter VW TDI has an oil change interval of 10,000 miles.

 

I thought OTR trucks had more advanced filtration and coolers than our semi-semis.

 

I said the same Neal...

And I mistakenly mentioned the year, it was an '04.

I had told him I would not try to diagnose his low power issue without at a minimum of the oil and filter changes with genuine motorcraft parts. Even though his recent issue pointed towards a sticking turbo and EGR valve. I was surprised though that after cleaning the turbo and EGR the "power" that he had was as good as he and I thought it should be, and the oil change didn't appear to "help" any with his low power issue...Makes me wonder how long he would have neglected that truck if he didn't have a larger issue.

 

Here is the page for the Donaldson filter for ISX15...Some guys add Luber-finers and supplemental filtering, but just stock it is this filter (17 micron). I'm not sure what you mean by "more advanced oil coolers" though. Oil temperature is about the same on all the trucks I drive...after thoroughly warmed up and worked, it is about the same as coolant temperature...210 or so.

 

I'm willing to bet that neglect will bite him in the butt in the next 10k miles. My 6.0l had some spotty maintenance before I got it, but never anything that bad, and I've been constantly chasing oil induced issues since I got it...

 

Dang, i'm sitting on 7k since last change with t6 and it bugs the crap out of me. I guess I need to relax...

 

Yep. You could probably double that mileage.

 

Yes, get a cold beer and dont worry about it. Just so you know, with my bypass filtration setup, here is a thread on my last oil change. I was doing 7500-10k mile changes before my bypass filter with no ill effects.

 

Many of us, including myself, are guilty of going beyond the recommended oil change intervals. While most won't notice any problems, it doesn't mean that there isn't an issue developing. These recommendations by the manufacturers are there to promote the longest life possible out of these engines. So while extending your oil change intervals beyond the OEM recommendations might not show immediate damage or problems, doing so continuously could eventually catch up to you in the long run.

I would never once consider going any interval recommended by an oil company. Those recommendations factor in only the oil life on the average engine, and does not reflect the specific needs of certain motors, such as the 7.3L PSD that utilize a high pressure oil-driven injection system.

Furthermore, an oil analysis may help or hurt, depending on how the end user interprets and understands the data. What information is reflected in an oil analysis is the typical values for that particular oil group, but does not necessarily reflect what is "normal" for a specific engine type. In other words, an oil analysis does not necessarily reflect what are the acceptable values by the engine manufacturer. So while an analysis may show the oil as having more life up to "X" miles remaining, it doesn't always mean that those are acceptable values for a specific engine or recommended by the OEM manufacturer.

As for filtration bypass systems and other oil system modifications, those should be treated as precautionary safeguards rather than systems to extend oil change intervals.

With that said, I tend to change my oil every 5,000 miles, even though my truck endures "severe" rather than "normal" driving conditions most of the time. Given the design of the engine and the utilization of the high pressure oil pump, I personally would not endorse extended oil changes on these engines. For most other engines it wouldn't be as much of a problem, but engine oil in the 7.3L's endures much more punishment thanks to the HPOP. Even the most robust oils will shear and break down.

 

I have worked with a diesel mechanic for IH and said with the new oils such as Shell Rotella 15-40. You can go 10,000 with no problems. Thats what I do with my 2001 7.3.