truck fleet oil samples

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I own a trucking company ordered 3 brand new glider trucks 389 peterbilts with cat reman engines (550hp) going on 3 years old now around 480k miles and I have one truck that has had high copper in the samples started out at 88ppm of copper brought truck in and dropped oil as soon as I seen that to try and clean it up didn't do anything really... now have 598ppm of copper in the oil once I seen this I pulled the pan off and rolled main bearings and rod bearings in it then installed new oil cooler, checked air compressor oil pan and it was clean, found one main bearing that was rubbed down to the copper and one rod bearing, just upset bearings should last 750k miles not 500k miles ......the sister to this truck has the same problem but instead of it being a gradual increase it just spiked from 12 ppm to 348ppm of copper in the oil, live in south Dakota, use Schafer's oil supreme 7000, sales men and lab scientists all tell me I am good to run 20k miles on there oil after seeing these bearings and going through this I am having a hard time believing in there product, we have been using it for 20 years and never had a problem sales men blamed the cat bearings well that's [censored] in my opinion I use to work at CAT was a engine specialist there and I never ever seen this before, this oil is a 50 to 50 blend of regular deo and synthetic at CAT they just use regular deo, and the oil change interval was 12,000 miles at 550 hp the more hp you run the lower the miles you run on your oil these guys are telling me that doesn't matter I am just looking for a answer on this if someone could help me figure this out I would appreciate it. Its not just the reman engines I have 4 other trucks that are starting to do the same exact thing.

thanks guys please comment If you have any ideas
 
Couple questions...Who remaned the engines CAT or some other shop? There is one rebuilder out there..popular with the glider crowd who is doing really substandard work. When did the copper spikes happen..at new..after an oil cooler replacement?
 
If you worked on Cat engines in a former life, you're much more knowledgeable than me on the subject of what's normal for bearing wear. However, if those engines weren't remanufactured by Cat, then I would suspect the problem stems from the company that did reman them. Maybe not genuine Cat bearings or could they have been improperly torqued? I've never installed bearings so....
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I have owned/operated a C15 Cat, (550hp/1850 torque) and it went nearly a million miles without any major problems, certainly no bearings wore out. I only saw high copper when it was new and leaching from the oil cooler. I started at 18k mile intervals and quickly moved to 30k mile oci. When I installed a bypass filter (FS 2500), I worked my way up to 60k miles between drains. Another C15 was purchased with near 300k miles and went to 750k miles without any major work using 30k mile oci. My trucks have always been strictly in OTR operations, no short haul or off road business, so that helps.

I've purchased a mixture of new and used trucks and when looking at the used truck ads, it was common to see trucks with only 500k-750k miles with "fresh rods and mains". I don't know how many of those were really necessary.
 
Originally Posted By: csandste
Diagram that sentence.


He nearly made it through the entire post without using a period, but then threw in an ellipsis.
 
Originally Posted By: leje0306
Originally Posted By: csandste
Diagram that sentence.


He nearly made it through the entire post without using a period, but then threw in an ellipsis.


Making fun of people is not cool guys.
 
A spike in copper on a UOA does not necessarily mean there is a problem. It can be from the oil cooler, or a particle streak. I had some Schaeffer UOA's on John Deere engines come back with 300-400 ppm of copper. We found nothing wrong mechanically and attributed the copper to leaching from the oil cooler. Both engines had high hours on them, and we put thousands more hours on them without an issue.

You found a few bearings with copper showing...was the clearance out of spec.? It sounds like some sort of assembly inconsistency (clearance not right, crankshaft not true, etc). Even so, the engines could have run a long time without changing anything.

Nice truck and engine combination by the way. A 6NZ C15 is about as good as it gets in my opinion.
 
I'm a little confused by the "rolling" rod & main bearings into it-does that mean that the crankshaft wasn't removed, measured with a micrometer, or inspected, the block wasn't checked for high spots under the mains, no Plastigage was used to check oil clearances? Sounds strange to me (but I've only rebuilt passenger car & light truck gas engines, maybe big diesels are different?).
 
The problem, as I see it, is not the oil. If the oil gets you 100,000 miles, it's good enough to go the distance. There is a mechanical issue here in each case. Too bad, but it happens.

There is a reason CAT rebuilds are more expensive than the indy's ...
 
Originally Posted By: bullwinkle
I'm a little confused by the "rolling" rod & main bearings into it-does that mean that the crankshaft wasn't removed, measured with a micrometer, or inspected, the block wasn't checked for high spots under the mains, no Plastigage was used to check oil clearances? Sounds strange to me (but I've only rebuilt passenger car & light truck gas engines, maybe big diesels are different?).


Rolling in bearings is...or was...a common practice and required maintenance on some engines. CAT on highway engines in the 70's and early 80's it was common to roll new bearings in at a specified mileage (needed or not). The process is just like it sounds, drop the oil pan, remove one bearing cap, replace the lower bearing shell, insert a special tool in the oil feed hole in the crankshaft, rotate the crank to push the old upper bearing out, install the new bearing the same way, re install the cap and move on to the next one. It sounds crude...and by today's standards it is..but it was fairly common. Oils and bearings have gotten much better. Some less than quality in-frame overhauls will do this without plastigaging anything and either just throw stock bearings back in..or worse yet..assume it needs oversize bearings and throw them in. Some lousy shops will also call this kind of inframe nonsense a "re-man" when a true re-man is a factory done out of frame complete re-manufacturing with the required measurements and reconditioning taking place (usually you swap out the engine).
 
Originally Posted By: bullwinkle
....does that mean that the crankshaft wasn't removed, measured with a micrometer, or inspected, the block wasn't checked for high spots under the mains, no Plastigage was used to check oil clearances?


Bad machine work or bad clearances by the independent shop somewhere along the line.

I used to do a lot of "Rings, bearings, and timing chain overhauls" in the 70's and 80's ($99 a kit!) and these engines often went another 100,000 miles without problems. A lot of the ones I did are still running today, 30 years later. I don't think you can get away with such cheap work on a diesel that works hard (1800 pounds foot of torque) for over 500,000 with out problems.

I will say this - if you roll in bearings, you need to look at the crank journals very closely. If you don't see a perfect surface, something wasn't measured right and the crank needs to come out an be "made right" again before it goes back in, or it'll just keep eating bearings.
 
Originally Posted By: BrocLuno
The problem, as I see it, is not the oil. If the oil gets you 100,000 miles, it's good enough to go the distance. There is a mechanical issue here in each case. Too bad, but it happens.

There is a reason CAT rebuilds are more expensive than the indy's ...


see I thought the same thing until I looked at other engines I have in the line up have another truck that's a mxs cat (twin turbo) showing the same thing and it was rebuilt 4 years ago around the same time as the gliders, everything brand new crank, piston packs, cam, head, rocker arms, jake brake housings, iva housings, wire harness, ecm, you name it I put it in.
 
Originally Posted By: Rob_Roy
A spike in copper on a UOA does not necessarily mean there is a problem. It can be from the oil cooler, or a particle streak. I had some Schaeffer UOA's on John Deere engines come back with 300-400 ppm of copper. We found nothing wrong mechanically and attributed the copper to leaching from the oil cooler. Both engines had high hours on them, and we put thousands more hours on them without an issue.

You found a few bearings with copper showing...was the clearance out of spec.? It sounds like some sort of assembly inconsistency (clearance not right, crankshaft not true, etc). Even so, the engines could have run a long time without changing anything.

Nice truck and engine combination by the way. A 6NZ C15 is about as good as it gets in my opinion.


thanks rob that's kind of what I am thinking oil samples are nice but they sure can drive a guy nuts if you study them a lot its hard enough trying to find a good driver but keeping everything in tip top shape is important to me having 6 engines go down would just take the profit out of the year for me.
 
I don't know much about big truck engines (although I drive a truck) but with a car engine if you have some copper showing it's not necessarily worn out.
 
Originally Posted By: AndrewThomass
Its not just the reman engines I have 4 other trucks that are starting to do the same exact thing.

thanks guys please comment If you have any ideas


OK, this is a clue that the reman probably isn't the issue. In my old life I ran about a hundred Cats and Mack diesels. First, I would quit mixing oil in the engine. Buy an approved CAT oil and stick to it. Don't worry about full synthetics, millions of miles are run by the big fleets on semi syn and even conventional oils. They work just fine. Second, go over the air intakes with a fine tooth comb. I worked for a fleet where I found drivers poking holes in the intake tubes so they could spray ether in closer to the engine. It makes a great place for dirt to enter. Also, look for any crankcase vents that may be missing the filter. Depending on the model of engine there may be a paper filter or a steel mesh filter in a valve cover to keep dirt out of the crankcase.

The intake is pressurized under load but at idle it usually is not (unless it's an ACERT). At idle you may be pulling dirty air through a leak.
 
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