Oil changes...

The mains and rod bearings absorb little bits of trash floating around in the oil, remember the oil filter only collects pieces over 30 micron, I have changed many bearings, they are rough, feel like a fine sand paper. If a mechanic ever told me that after removing the oil pan, separator plate and oil pump that the bearings were OK I would fire him. The bearings are cheap, the labour to get to them is the expense, especially on a CAT C15. The thrusts should be tested, for wear. The oil pump, I always change the regulator spring, and inspect the pump taking special care on the regulator spool valve, I polish it and the bore. I always change the "O" rings and file the outlet pipe to block surface.
There is a big difference between being a mechanic and a parts changer.
Doing a bearing change first I use to get the driver to add a gallon of ATF Dex 3 to the oil 1/2 hour driving time before He gets to the shop. I wash the front 1/2 of the truck, especially the inside of the springs and the front axle, with the engine running at 1200 RPM, When it is immaculate I put it in the bay, Drain the oil, I remove the oil pressure guage hose, and install a regulator and put in 50 lbs air. I Lift the engine up, and install 2 inch square tubes, spacers to keep the engine higher from the axle. I remove 3/4 of the bolts from the oil pan, I reduce the preasure on the air to about 10 lbs, and punch a hole in the filter. When it is drained I raise the preasure to full shop air, that blows all the oil out of the unit. I remove the air line and reconnect the hose. I then do the bearing roll in, Looking for bent oil nozzles, anything out of the normal, On assembly I put the oil in the unit thru the oil galley plug to preasure lube the system.
Just a thought!

 

That's what I'm saying. Why push something that isn't that big of a expense. 15k Mobil with 1 gal of lucas oil stabilizer, an new oil filters. Fuel filters every 10k firing it up with a injector cleaner straight out of filter. Greased and adjustments every 7500 on frame and brakes.

Oil breaks down so much over extreme temperatures. On these newer motors where the oil temps are extremely high, there is no way I would run them over 15k

 

That would be true, but spun bearings happen even with those that change oils more frequently. It is not always due to the oil or the change interval. Sometimes quality control on the component itself may be lacking. If changing oil every 10,000 to 15,000 miles was any kind of a guarantee, then no one would have any problems over the course of million miles. But things do happen, and they can happen to anyone. I am not sure that, when broken down, that the percentage of problems is higher for those that extend the drains a little compared to those that don't. it makes one feel good that they perceive they are protecting their engine better, but I have not seen any documented evidence, either way, that it really is.

Now, Detroit states that my pre-egr Series 60 should have oil changed at 15,000 miles. No problem. But if one digs into the official lube and maintenance manual from Detroit, they state that if I use a Detroit 93K218 rated engine oil (most modern oils are rated at that), they show oil changes for 22,500 miles. I run a bypass unit, run the oil out to 25,000, change the bypass filter in the middle and at the oil change. I could go much longer based on the oil sample results, but I am comfortable with that. I have no desire to set any kind of record oil change interval. Extending the drains over 50% above the old recommend 15,000 mile interval is a comfortable level for me. A little bit of fresh oil gets put in when I change out the bypass filter.

Whatever floats a person's boat.

 

As a curiosity, what is it about Lucas Oil Stabilizer that impresses you? Do you think that the Mobil is unstable? What is in LOS that makes you think that it can do a better job than the oil itself?

 

The little marketing gizmo with the gears you turn by hand while watching through the plexiglass get a lot of folks thinking that Lucas stuff is awesome...

 

Motorkote uses chlorinated paraffin.

http://www.opieoils.co.uk/pdfs/Beware-miracle-additives.doc

 

And you know that the oil is breaking down before 15K how? Show us some oil sample tests confirming that the oil is breaking down after 15K. I have dozens and dozens of used oil sample test results and my oil must have never gotten the memo that it was supposed to break down before 15k. That is all the oil I have used since 1995. My oil changes have always been 20-30,000 mile intervals. Not a spun bearing, failed turbo, etc. All the oil samples show the oil was still within viscosity specs and all wear metals well below tolerance levels and additive package of the oil had not depleted below change limits.

It is interesting how people who couldn't tell you what makes up the formulation of the particular motor oil they are using seem to know more than the folks who built the motor and make the motor oil on how often it should be changed. They won't trust the OEM on what they recommend for oil change intervals on the motor they spent millions of dollars in R&D developing, and they won't trust the motor oil company that they can make a oil that will protect the motor as long as the OEM says. And they base that mistrust on what? Years and years of experience as tribologists and analyzing thousands of test results? Nope. Just on what they heard over a lunch counter and the marketing genius of someone like Forrest Lucas.

 

And make no mistake; Forrest Lucas IS a master salesman. Not a bad guy; or anything of the sort. But he could sell sizzle and smell and make you think it's steak.

 

Hours are a better measure than Miles!
Different applications and operators can greatly change how long it runs compared to how far it's driven!!
Oil Analysis is a good thing when done well.. (not contaminated and have a history of them to see trends)

Different engines have different needs, Read their suggestions.

Know of a fleet that was once all Mack (old school) 237's , 300's , 300+'s They took a sample and swapped the filters between 25k and 30k miles, then changed oil at 100k miles, yes 100k miles, all OTR. and that waste oil with 100k on it got dumped into the fleet's bulk diesel fuel tank and burned in the trucks!! that fleet would avg. an inframe near the 800k to 1 million mark and had several trucks with 2 plus million when retired.
Now their first series 60 detriot was JUNK at about 700k when the timing gear lost it's teeth. they learned the hard way not all engines can handle the same treatment!!

 

And that is true! I monitor both miles and hours. All good points!