Cummins in a semi....problems???

[AndrewGray]

Hi all. We are looking to buy another semi for our cattle operation. It will be use commercially for trucking. We have been looking at a few but have it narrowed down to 2 frieghtliners. Both are 2001 or 2002 . One has the cat, but Im not sure what model of engine , not really interested in the cat. The other has a cummins. The dealer said it is the ISX or ISM series engine. Im not sure if he is right if those are the ones in OTR trucks. He said that the cummins spin the main bearings and ruin the cranks at about 300,000 miles . He said every one he has got in has had that problem. I would love to get the cummins but if this is a known and common problem then I will look harder at the cat or a detroit. Our other truck has a detroit with 500,000 miles on it and no problems. I would like to know on this soon as the truck will sell early next week Thanks for any help.

 

[AKaiser]

JMHO: If the CAT is a 3406 (or a 3176,) buy it if it's in good shape. Many OTR Owner-Operators swear by Cats and Peterbuilts.

 

[Dl5treez]

For what it's worth, we've had more problems with the pre-EGR Series 60 Detroits in our fleet than the pre-EGR Cummins ISX series.



The Cummins with the EGR system have given us trouble, mostly with the EGR valves.



Can't help you with the main bearing thing, as I haven't come across it yet in our shop.

 

[bmoeller]

I'm partial to Cat in trucks, but the boss bought me a '03 KW with a 500hp ISX (15L) Cummins. It pulls HARD. The Jake works GREAT. Mileage in the mid 5's with a bullrack. From talking to other drivers with a 475 Cat, pulling a bullrack with 379 Petes, they can't hardly get over 4. 7mpg with their trucks. Not sure if that is all road miles or idle time sleeping included. Even if I leave the truck running while I sleep, I can still get 5. 2+.



It does use an electric pump (ECM controlled) to prime the system before starting and when changing the fuel filters because of the dual overhead cams. It has a cam driven mechanical pump on the top side of the engine that is used during operation. Weird, but it works.



Does have a few quirks, though. Not sure what is up yet. Dealer did replace the ECM shortly after we got it. It took a dump right before I was to leave on a run. Might have been litghtning, though. Not sure. Ran fine the day before it happened. Had a couple of blown fuses. 31k miles later, still fine there.



It does idle goofy and shakes a bit on the top-end (and makes the boost gauge shake). Not sure if it is an injector, or what. Dealer siad they were fine, though.



Truck has over 400k on the truck.



From what I've been told, the '01-'02 ISX engines have the fewest problems. Ours is a '02 build. '03- up have EGR.

 

[AndrewGray]

I guess we have been lucky with the detroit. I just wonder why he he said that the cummins was having those problems. I never heard of that before but he is a very reputable dealer. The have a dealership and have a used parts business and he said he buys trucks from fleets and he ran across the crank problem a lot. I sure would like to have the cummins but has me leary. Still pndering tho.

 

[bmoeller]

I'm guessing the trucks he gets to part out haven't been taken care of very well.



Really don't know what to say bout it. This is the first big Cummins we've had since the BC 855 in the old cabover. Other than the quirks, I really like the engine. If we could get it tip-top, I'd be happy.



Have a 430hp C12 in another truck. It pulls hard (albeit not quite as strong as the ISX), too, and can get mid 6's with it, with the same loads.

 

[JFaulkner]

Ive got an '01 and an '02 C15 Cat with absolutely no problems from either. As I've said before, don't look at the engine brand to determine fuel milage. The driver has FAR more to do with milage than the brand of engine ever could. I know a guy that has an '03 ISX and other than a rash of sensor problems it's been realitively problem free. It did have a problem with the seal at the bottom of the wet sleve and started burning water, which was fixed under warranty and I'm sure was just a case of bad luck. Not sure on fuel milage since the loads average 90k net, so good fuel milage is a distant dream.

 

[DMcPherson]

Thats a load. I doubt that it is an ism, as that is an 11 liter. it could be but probably an isx. neither enigne or any engine that Cummins makes for that matter has a problem spinning bearings. especially main bearings. I would try and drive both and see what you like,but working for cummins I would say that the ISX is a better enigne,

 

[AndrewGray]

I feel better reading the replys here. I will give the cummins a better look. I have asked around here at diesel shops and they were not aware of or have seen a cummins with that problem. I think you are right that is trucks he is getting in from small fleets or something where they are neglected. I know the cummins will do a little better in mileage than a cat but it all depends on the driver. I run the truck we got with the detroit and i consistantly run a little over 6 mpg with it and it does have some idle time but not a lot. Im goin to look at the cummins and the cat and see how I like them. I wouldnt mind gettin them in a KW or Pete but their turning radius is too much for our needs. I haul a lot of cattle from the back roads and yards and need the power and the short wheel base. Our trailers are tri-ax and so is the truck . I have had my belly full of cab - overs..... never again! Thanks for the help all.

 

[Andersonville]

If I was going to buy a used truck I would look for a Crete or Schneider or Walmart used tractor. It will have about 400k miles BUT the engine will have been run with synthetic fluids and been serviced on schedule. My truck driving O/O buddy tells me Cats and Cummins are 500k engines and Detroits are 1 million k engines. Aerodynamic trucks are harder to work on but easier on fuel. Long nose Petes and W900's etc are easier to work on but hard on fuel. No aerodynamics. You can feel the wind wave they are pushing when they pass you going either way. The best riding quietest truck for me was a Volvo,the best fuel mileage I ever got was a cabover Pete! 8mpg at 62mph empty or loaded! It had a 425 Detroit with a 10 speed and 5. 33 rears! Getting in and out of it was a real pain. Cats are real prickly about fuel quality and maintenance. When you see a used fuel filter on the side of the road,most of them will say CAT on them. Just my . 02. Good Luck

 

[bmoeller]

If I was going to buy a used truck I would look for a Crete or Schneider or Walmart used tractor.

TMC usually trades at 3-400K. Their stuff seems to be taken care of pretty well. I know the drivers get bonuses for good mileage and keeping the trucks clean. Have a neighbor that is running one of their old trucks. Never had any problems with it, that I'm aware of. He takes good care of his trucks, too. Almost show-n-shine shape. I'm more partial to his W900L or his T-800. His T8 did throw a rod out thru the block though. Don't know why. I suspect EGT issues. Ruined piston.



Driving habits seem to be less of an issue anymore. Any of the trucks we have, I usually get the best mileage out of them as apposed to some of the others that have run them. I don't hot-rod shift them, but do generally run with the hammer down. Not so much as speeding, but usually the first at the top of a hill, or that lots of guys (mostly company drivers) won't run the 65-75mph speed limits, but I do. Whether I drive easy or not, it seems to have neglible effect on mileage. Fuel quality and headwinds are the biggest factors I see with mileage, of having to run with 55mph speed limits in hills.



The '95 Mack w/ E7 350 & 4. 17 gears/ tall 24. 5 rubber gets 6. 1, daycab T8 w/ 430hp C12 gets 6. 2-6. 6, and the new one gets mid 5's with the same loads. Both KWs have the 3. 90s. All driven the same. That is on summer fuel, though. Usually lose . 75-1. 5mpg on all of them with winter blend and no additives (Howes).



With 2 of the trucks having 3. 90 gears and tall 22. 5 rubber, 15-1600 RPMs seems to be a sweet spot.

 

[EricBu12]

i drive for Fed-ex and we have Volvo trucks and the new ones have the ISX Cummins in them,... So far, it seems the cummins is using less oil, pulls great, the 6 position jake is wonderfull and the milage is good... Cant go wrong with either engine...

 

[DMcPherson]

if you wanted a pete yo uwould have to go either 377 or 378, I think they would suit your turning needs, and remember that the resale on a pete or Kw is way higher than any other truck out there. Volvos are dirt cheap, you cant get a pete twice as old for what you can buy a volvo for, or FL for that matter. and yes Im biased I work for Cummins and came from peterbilt.

 

[AndrewGray]

The truck we are runnin now is a 2000 volvo with the detroit. I like the truck cause it turns short about like a cab-over and rides great, but its gettin close to 500,000 on it so its time for a different one. We are looking for used but with under 200,000 hopefully closer to 100,000. We are even thinkin of tryin the auto. We found a couple with the autos and may take them on a load or two and see how they work. I have talked to a few guys that have them and they said they wouldnt go back to gear jammin. We pull heavy loads throught hills so want to be sure they hold up. The mechanic we use said they work well. Matter of fact he is the one that told us we should at least try one out. So that may happen too.

 

[Dl5treez]

Ya know... . I got to thinkin' tonight at work--bad idea I know--but maybe the truck sales dude has got the ISX series confused with the N14 when it comes to main bearing issues.



The N14s had/have a very well-known fretting issue, and Cummins has issued quite the in-depth service bulletin about it.



Just a thought...



Dan-

 

[bmoeller]

The KW trucks (at least the T8 and T-6 trucks) turn really good.