CM871 Oil sample help

[Rawze]

(01-31-2024 )Aussie Steve Wrote:  ...
I sample oils and change them based on HRS only
...
The X15 we have can push the oil change to 500 hrs but is changed at 250. I feel this is cheap insurance.

Just adding to the conversation here ...

Oil sampling is a good troubleshooting tool to identify issues, but it should not be relied on for determining oil change intervals. Doing an oil sample at every oil change and sending it off can be a bit of a waste of moneys unless they tracking some specific trends or using the data for some reason, like how a particular brand of oil is performing, etc.

I.E.> Its useful info, but don't believe all you see with that oil sampling. Here is why ...

Oil sampling alone will not show separation and a few other things. I see a lot of people get caught up in that false game of "change it based on sampling alone" for the purpose of trying to save moneys on oil changes.

Someone should NEVER rely solely on oil sampling for oil change intervals. That is a quick way to shorten the life of the engine.

Believe me.. I have seen it way too many times over the 30+ years of my career, and again with these engines, of people doing this and ending up with lots of expensive problems.

As far as vehicles and the engine oil goes, the best someone can get for oil change intervals (balancing longevity vs. cost of oil changes) is going to be doing so based on average fuel mileage (or fuel consumed per hour for engines that PTO a lot, etc.). This is because there is a direct correlation between how hard you work your engine vs. how long the oil lasts and/or separates, etc.

What I mean by balancing longevity vs. costs is that there is an optimum point where changing oil more often does not mean you get any more life from the engine as a whole.

Change oil too often, and it simply costs someone more without any engine longevity benefits.
.. or ..
Don't change it often enough vs. its fuel consumption, and the little moneys someone saved in the long run is far less than its now costing them to pull that engine apart sooner than it should have.


Its a balancing act where there is an actual optimum, so that operating costs, and/ or effort is not wasted.

For an ISX ... including that X15, here are the numbers...

Quote:If your average fuel mileage every 10,000 miles is ...

less than 5 MG -- Change your oil every 8,000 miles or so.

5 - 6 MPG -- Change your oil every 10,000 - 12,000 miles or so.

6 - 7 MPG -- Change your oil every 12,000 - 15,000 miles or so.

7 - 8 MPG -- Change your oil every 15,000 - 18,000 miles or so.

8 - 9 MPG -- Change your oil every 18,000 - 22,000 miles or so.

above 9 MPG -- Change your oil every 22,000 - 28,000 miles or so.

ref: http://rawze.com/forums/showthread.php?t...617#pid617

.. So... This means that the 500 hour interval (that is close to what the factory would recommends to make the mega-fleets happy) is absolutely ridiculous!>.. and would only be for a bobtail truck not hauling any freight!.

And ...NO ... Using synthetic oils does not extend this at all.


===

All that aside, .. even so ... The most well cared for ISX's (not abused, and all care + all preventative maintenance done correctly) will always end up needing an inframe due to non-lubricated components any ways.
here are some more words on this: http://rawze.com/forums/showthread.php?t...5#pid76425