Detroit vs Cummins

@x1Heavy yea the little 12L isx love 1650 or so. Once they drop below 1500 they fall right off. Same powerband as the old 855's

 

Wrench says he can inframe a Cummins in a sand storm and it will start up and run for another 600K. He said you have to do a DD in a clean room.
He has a DD15 he's parting out that is now a boat anchor because the PLASTIC oil pick up fell off and it spun a bearing in like 10 seconds. He says DD say once they spin a crank bearing, cannot be rebuilt even with a new crank, will never be right.
DD leak a lot, that I know for a fact.

 

I know two-three trucks with spun bearings because of fallen plastic oil suction manifold. DD has changed the design but it's still plastic piece of junk. O yeah they have changed oil pump design since 2012 four times. Suction plastic manifold design was changed 5 times. If you don't believe me check Detroit's eParts catalog for 472 / 92U engines.

 

Some engines cannot be rebuilt back to normal tolerances once the certain bearings you speak of get spun. I had a 88 oldsmobile that was a joy for a 4 door car (Super charged V6 which is NOT THAT exciting in terms of sporty cars... but for a big ten ton barge this was a good engine...) that eventually spun the main bearings. The only remedy was to drop a new or replacement engine into that vehicle. (Far more cost than it's worth....)

If you are going to build a engine, the good ones are those that have the ability built in to be worked on after a event casualty that might be fatal to it such as spun bearings. Otherwise what you really have is a disposable engine, one that is not expect to have any value to anyone other than the trash can at some point.

 

Reading these comments does not help. It sounds like the Detroit DD is more reliable than the IX but cost more to fix.

 

At my job we have Cummins and Detroits in our Freightliners. The Detroits are much noisier and the jake brakes are a lot louder. Plus the Detroits wind the engine up to over 2K rpms downshifting with the jake brake on, while the Cummins only go to 1400 rpms with the engine brake on. The engine winding up like that sounds like it's going to explode! There's no difference in power between the two at work. Both take the same amount of time to accelerate to a certain point that I've timed. So if you want super quiet engine with a jake brake you can have on its highest setting while in town and not make any noise, get a Cummins. If you like a loud, noisy engine with a loud jake brake and an engine that sounds like it'll explode when stopping, get a Detroit.

 

DD15 was more reliable a couple yrs ago. Anything with a Cummins or Paccar was dirt cheap on many truck lots . I'm sure others will disagree .

 

Depends on which era you are talking about. The new X15 are turning out pretty good, better than the ISX. I know someone who bought 2 of them a year and a half ago and have been trouble free themselves, cant say that for the rest of the truck which are T880s. Dont know much about the DD.

 

I've asked the mechanics at my work "which is better?" One mechanic really likes DD because they are good with warranties. He knew of a school bus that had a Cummins engine and Cummins refused to do a warranty job saying it was owner error, but the mechanic claimed it was a common problem that the bus had and should have been covered. He said Cummins doesn't want to honor their warranties because they kind of have a lock on the market and know there isn't much competition, so they can refuse warranty work more often. Now another mechanic says both DD and Cummins are million mile engines. He said neither is easier to work on than the other. DD might be easier to fix one type of issue, but Cummins might be easier to work on for different issue. So he basically said both engines are about the same and both are really good.

 

ALWAYS the Benz. I've owned 2, a 2005, and 2008, 7 series. Worst cars on the planet. Pieces of junk. The benz is much more reliable and easier to fix when it does break. The 7 is a nicer car to drive, from a performance standpoint, feel and handling. But get use to the warning light bell sound when you turn the key.