I am contemplating using an FS 2500 oil bypass filter because we go on long camping trips of 7500 + miles every summer. I like to change my oil every 5k. With a bypass oil I may be able to extend the interval to 7500-10,000 miles.

I am not looking to extend to 25,000 miles and beyond.

 

 

Related to oil shearing... the oil in our engines has to serve as a hydraulic power fluid (to fire the injectors), and as such the oil in our specific engines is subjected to 60 times more pressure than the engine oil in other engines, including other diesel engines. As our oil, at pressures measured in the thousands, not just the tens, is squirting through small orifices and scraping past hard edges inside the injector galleries, it stands to reason that our oil would be subjected to more shear.

But that isn't the only issue with our oil serving as a hydraulic fluid. We also have to worry about oil aeration from churning. Bubbles of air in a hydraulic fluid are pockets for poor and jumpy hydraulic performance. The Caterpillar, Navistar, and Ford diesel engine oil specifications (the only three vehicle manufacturers that had diesels using engine oil as a hydraulic power fluid for the injectors) all call for anti aeration additives or a formulation that resists oil aeration. These additives deplete themselves, or become less effective, with use.

Therefore, even if your fancy FS-2500 kept your engine oil soot free and as clean and clear as baby oil, the issue becomes how good is the oil as a hydraulic fluid? How much air becomes entrained in the oil during the last 2,500 miles of your 7,500 mile interval? How broken down is the oil from high pressure pushing duty actuating the injectors? How much degradation in fuel injection and power performance will you experience in that last 2,500 miles with aerated and shear broken oil, that is otherwise still clean and lubricating adequately?

If you need to change the oil at a tighter interval (per Ford and Navistar's recommendation) anyway, then is the extra cost, extra leak points, and challenging packaging constraints in an E Series van worth it? Only you can decide... but these are some of the things I would weigh in the decision.

 

I haven't towed anything heavy in a long time, so my experience is basically driving without a load, and more highway miles than in-town miles. I will tow 5k pounds periodically, but that's about it. No big hills in this area either. Just remember, Ford is quick to tell you that if you work your engine hard, you should change the fluids and filters more frequently.

That said, I have seen no ill effects going 7500 miles on my oil. I use Mobil Delvac 1 or Mobil 1 TDT oil. I get it on sale and with rebates at $15 a gallon (or even less occasionally). I do not have additional oil filtration.

Not all oils shear at the same rate. From what I have seen the PAO oils will shear more slowly. The oils that have held up the best for me (with regards to shear) are Schaeffer 9000 (I never went over 5k miles with this oil though), Mobil Delvac 1, and Mobil 1 TDT - in that order. With the Mobil Delvac 1, I would drop just below the 40 wt point at 7.5k miles. I know people have used, and even towed, w/ 10W30 and seen no issues with it, but I haven't ever used that oil.

I have very little desire to try 10k miles. My injectors are all still original at 200k miles and I am not anxious to accelerate the development of stiction. It seems to me that it is a situation of diminishing returns after going to 7.5k mile OCI's. Even so, I can see why some folks would want to push it to 10k. I stopped at 7.5k due to that being Fords recommended max interval. Just my personal choice, nothing more. I do know that a few folks here have gone to 10k miles, maybe beyond (I just can't recall). There is one on the Org claiming 20k mile OCI's. Trouble is that you don't claim success with that decision unless you have 100k+ miles (maybe even 200k miles) operating like that. There is potentially a lot at stake for this "experimentation".

 

What's your average hour count over a 5000 mile OCI? What I'm getting at here is that the time-based interval is 200 hours; if you're spending the majority of your time moving at 70mph with no trailer and the oil heated up versus frequent cold starts and slow/idle use, the originally specified non-heavy use 7500 mile OCIs aren't really a problem to me.

Looking at my list, over the last 200 hours I drove 10,376 miles. If I was running either a 15W-40 or using Schaeffers again I might go back to 7500 mile OCIs, but since I only average about 10k a year I do 5k changes about every six months with Delo 400LE or T6.

 

I last used Delo 400LE. My driving is mostly freeways and highways @55-70 mph with a little city driving getting to the freeway or highway. I change the oil every 5-6k.

I pulled an oil sample today and am sending it to Blackstone tomorrow for analysis.

Compared to anything else on the 6.0, $100 oil changes is chump change. I can change the oil on the road as I have the Fumato valve for easy draining. Properly disposing of the spent oil can be as easy as going to one of those wax and oil chains that offer free recycling.

I have never checked engine hours and not sure where I can find this unless the ScanGauge tracks engine hours.

If it were not for the problem of oil shearing, the bypass filter would be a good idea for keeping the oil cleaner.

 

Here is the Delvac 1 $10 rebate. I want to make it to 7500 miles before I change the oil at my parents in Minnesota. Our trip starts in the San Francisco Bay area going to Great Smoky Mountain National Park and back to California.