A couple of questions..

[Rawze]

yeah... what those guys above said... all of it.

Don't over-srtress about the oil and fuel.. they are the things that make little to no difference unless you are actually abusing things. It is never the lubricated components that wear out in these ISX's when they do need an overhaul unless someone runs it without oil or something else stupid.

What does kill them prematurely is ...

* Liners fretting in the block (head gasket failure) from running and pushing the engine up hills, below 1500RPM its whole life. so Yeah,.. those ridiculously tall, engine killing rear ends that were not meant for hauling flowers, nonetheless 80,000 lbs are completely horrible!. That should be one of your actual investments after the purchase of a laptop and the cummins adapter you want to keep the truck long term.

Switching to a proper set of 3.90's from the garbage rear ends that you have now will also make it feel like it can actually pull good up the hills without killing the engine over time as well.

* Not doing an overhead adjustment every 250k miles will shorten the life of the cam(s). it is important to maintain that engine.. not just wait for the lights to come on before doing anything.

* ensuring that you grab a wrench or 2 and doing a thorough EGR tune-up about once a year + replacing the IMAP and other sensors as they get dirty and clogged up.. and the engine + DPF system will thank you for it. This is exactly the neglect of why 80% of so many people have after-treatment system issues, and there is no stealers$it or OEM repair shop about to do any of it for you. They are too stupid and are not trained properly for actually giving a damn about your engine and its actual long term health.

* A gallon of decent gear lube does wonders vs. that garbage pukas so it seems you already picked up on that fact.

* the biggest killer of the overhead cam and the turbo is the crank case filter. MAKE SURE that you use the maintenence-free one or gut the one you have until only the frame is left. Too many people forget about that filter and wonder why their turbo starts leaking oil or seizes up.. or why their overhead cam is chewed up. ref: http://rawze.com/forums/showthread.php?t...376#pid376

* Crank shaft damper at 500k miles unless you want to replace an expensive ECM at some point due to excess hi-frequency vibrations, etc.

* Keep it away, and do not be duped by those 'custom tuners' / 'delete' shops, etc.

90%+ of all delete/custom programs out there are absolutely harmful to these ISX's. Don't get caught up in their false promises and games. If you really need it de-mandated at some point (assuming you live in a country where that is ok to do).. then ask on here and get some proper recommendations for people that I have vettet out and reviewed their work first. That way your not replacing the head or head-gasket, or wasting way too much moneys, etc. only to have to do it all over again when you find out that the work was half-arssed.

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The list is longer than this. The emphasis here is that owning a red engine (cummins) is unlike other engines. you MUST keep after it like a red headed step child, wrench and screw driver in hand at all times ... or it will stab you in the back and cry real fast. They Like to be maintained.. and will lay down on you fast if you do not. This means that the only advantage to owning one is the fact that you can work on it yourself.

Fortunately, all the info the OEM has + engineering software, programming it, working on it, diagrams,,.. everything literally.. is out there and will benefit the person who uses those resources. This is also why there are die-hard fans of the engine out here on my forum. No other brand of engine is this open and available for the owner to learn to maintain and rebuild, etc. for themselves so easily.

Signup to quickserv.com and get access for free to all the diagrams, and other info on how to maintain and repair everything on that engine. Get a knock-off inline-6 adapter and a cheap laptop.. get set up to talk to your engine and troubleshoot it, and perform tests when needed .. BEFORE you are on the side of the road somewhere. Don't be the typical victim, endlessly chasing problems.. but become the owner of that ship, and eventually the master of what you have. these are the skills needed that make moneys out here that you can keep long term in today's modern era of trucking.