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This is to everyone that figures the Cummin's is the most reliable engine.
My boss has an 2007 Dodge Cummin's, cant remember if its the 6.7 or the 5.9, but the truck doesnt even have 80k on it. Anyhow, he took the truck to the dealer to get looked at (Towed to dealer) and they found that a rod had gone completely through the block :rof. Truck had absolutely no mods done to it either.

Second is my dad's old company truck. Truck was an 2005 Dodge Cummin's 5.9 and the truck had 75k on it. One day it started blowing smoke and had no power and CEL was on. Towed it to the dealership and all six injectors had gone out:eek:at the same time.:confused: Truck was also completely stock since day one.

Third was a buddy of mine. 2004 Dodge 5.9 Cummin's. Truck had 100k on it, and was not stock by no means. Two chips (Not sure which ones), exhaust, CAI, and it was lifted and everything to. He was driving it home one day and the motor had locked up on him. This one had spun a rod bearing and i cant remember exact details of what happened. He ended up rebuilding it himself (.030 over-bore) with new injectors, bigger turbo, same chips and all that.:rockin

For everyone that figures the Cummin's is the most reliable engine out there, i completely beg to differ. Only engine i have seen to date that can handle the abuse (so far) is the DMax:D
 

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On the two that had rod issues. Hey it happens. I've had stokers and d-maxes fail at low miles and stock. All engine builders buid a bad one here and there.

For the one that had the injectors fail. I personaly dought all six where bad at once. It sounds more like the dealer was lazy and didn't want to pinpoint the issue. And injectors just like the d-max are not built by cummins they run very similar bosch injectors as the lly+ engines have.
 

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cummis reliability

my dads 03 ham tough dropped the fan pulley-thru the rad it should have been warranty but cause he was in Az (we are from Alberta Canada) the local (Parker Arizony) stealer told him he was s.o.l. $1500 repair
 

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common rail cummins will get you in the end. don't do it.
 

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Really? Look it doesn't matter all engines are going to have trouble it doesnt matter how well built they are when you build a hundred thousand of them there are bound to be some bad apples in the group. Look at the Dmax 01-04 some of these engines ate injectors like a fat kid on twinkies, Mine has almost 130K on stock injectors knock on wood. My uncles 05 powerstroke has over 150K on it and has never had an injector job or anything major wrong to where it had to be towed it was leaking diesel at one point but that was the shop he took it to on the flip side our ag truck at school which is the same year powerstroke had 6 injectors go out in 4 months with only about 50 thousand on it. The point is all mass produced engines or any engine for that matter is going to have problems in isolated cases not every engine built will have the problem but there will be problems in isolated cases. I call your friends and dads cummins problems bad luck. :rant
 

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I completely agree that there are a few bad ones and what not here and there. Every truck is different just like people. Some are great, some are ok, and some are just trouble. Doesn't matter if its duramax, powerstroke, or cummins. Agree with everyone sayin that.
 

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Like others have said, Each company has had a few misfits. They are all great engines, it just comes down to personal preference. To help the cummin's guys what about the million mile cummin's in DP? i know its a 12v but still.
And somewhere i read about a CR5.9 with 400k and lots of go fast parts still running strong so they cant all be terrible.. lol Just my .02
 

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This is to everyone that figures the Cummin's is the most reliable engine.
My boss has an 2007 Dodge Cummin's, cant remember if its the 6.7 or the 5.9, but the truck doesnt even have 80k on it. Anyhow, he took the truck to the dealer to get looked at (Towed to dealer) and they found that a rod had gone completely through the block :rof. Truck had absolutely no mods done to it either.

Second is my dad's old company truck. Truck was an 2005 Dodge Cummin's 5.9 and the truck had 75k on it. One day it started blowing smoke and had no power and CEL was on. Towed it to the dealership and all six injectors had gone out:eek:at the same time.:confused: Truck was also completely stock since day one.

Third was a buddy of mine. 2004 Dodge 5.9 Cummin's. Truck had 100k on it, and was not stock by no means. Two chips (Not sure which ones), exhaust, CAI, and it was lifted and everything to. He was driving it home one day and the motor had locked up on him. This one had spun a rod bearing and i cant remember exact details of what happened. He ended up rebuilding it himself (.030 over-bore) with new injectors, bigger turbo, same chips and all that.:rockin

For everyone that figures the Cummin's is the most reliable engine out there, i completely beg to differ. Only engine i have seen to date that can handle the abuse (so far) is the DMax:D
The two issues dealing with rods and injectors can happen with any brand I don't care which it is, duramax, powerstroke, cummins. I'm curious also as to how the engines have been treated.

As for your buddy with the 04 that blew his engine? You say he had two chips? That's the likely culprit. I'm assuming he had a programmer and then had a chip stacked with it. I believe most of the programmers for the cummins increase rail pressure. And seeing as how most chips for it as well increase the rail pressure, it's pretty obvious that a blown engine will result seeing as how rail pressures can be well above 28k with stacking.

Each of the big 3 diesel engines have their batch of bad engines so we could literally sit here all day and exchange stories of how and why one is better than the other. I don't think cummins is the most reliable, but rather it's one of three competing diesel engines on the pickup market that is rather appealing to me. Parts are generally cheaper. Inline engine so it's naturally balanced. Two less cylinders than either powerstroke or duramax, yet the power ratings are comparable. The block is stiff as nails, having 7 main bearings. The stock bottom end in a 5.9 is easily capable of 4k rpms. It's a good idea however to get some aftermarket valve springs when trying to turn those high rpms with a cummins. The support base is there for cummins. Christ I can literally drive 40 miles from my house and there's four shops off the top of my head that are cummins distributors. One is the dodge dealer, one is a machine shop, and the other two are trucking shops. If it's on the engine, the trucking shops usually can get you better deals than the dealer or machine shop. Cummins is fairly easy to work on. Air enters through the turbo, flows through the intercooler, which then enters the intake manifold, etc. It's easy to follow air flow through the engine making it easier to diagnose air problems.

And to be fair about this I, in no way, know everything there is to know about anything lol. There is a lot for me to learn. Now with that said Lets talk about reliability here. I was having an electrical issue with the tach in cab on my 01 dodge. Almost the same day that issue started my oil pressure gauge stopped working. I figured it was electrical. Well long story short i really had lost oil pressure. And had been running that way for two weeks before the engine decided to spin a bearing. And when I mean no oil pressure, I mean it had no oil pressure due to there being less than two quarts in the pan. I'm baffled as to how the top end of the engine was even going.
Literally the only damage I did was chewing up number 6 rod bearing, while starting to score number 5. no damage whatsoever to the main caps, no scored cylinder walls. The damage was contained to just the crank and the back two rods. Don't sit there and tell me about reliability when I same as run a that cummins same as without oil for two weeks, start knocking, and find that damage was very little in my opinion. I just won't believe you:) Of course it wouldn't have knocked if I wasn't being a dumbazz at the time.:rolleyes::rolleyes::rolleyes:

Then lets sit and talk about what's wrong with the engine. The fact that it gets power to the ground with a transmission that is basically a carryover from the gassers. An inline design isn't really conservative on space, it's long, so it is definitely more challenging to fit. The engine itself fully dressed is approximately 1150 pounds, so one will see issues with the front end more so than the duramax. Then the engine is enclosed around a body that isn't high end by any means. And let's not forget that the ecm coding is copyright protected so the "efi live" tuning in the cummins world won't happen anytime soon so we're limited to canned tunes. Unless on the newer common rail cummins one has the cash to drop on a stand alone ecm which are just coming to market, then we finally get full control of the engine. Still not nearly as affordable as efi live.

I don't mind any of the things that are considered "wrong" by some. I figure it's the nature of the beast, and thus grow to like it even more lol.

Oh and I must poke some fun at your boss because I don't think many people like their bosses no matter what their particular job is. Lets assume that the tale is true of the rod going through the block. The huge oil puddle resulting wasn't an indication? I'm quite the doofus but I've seen a rod come out of a block. Oil gushes everywhere, almost like water. I'm willing to bet though since you said your bosses pickup I'm assuming it to be the company pickup, in which case I can fully understand why something like that could happen. Nobody ever takes care of the company pickup. Gets even worse when it's a pickup that the employees like.

Well posting this was quite fun. I killed some time. yeehaw :D
 

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04 dodge 380k unknown life now is a towtruck for my dads company and now has a superchips programmer on tow weights injectors are shot and need replaced

05 rollback 480k had around 400k on it when we got it in late 07 it had a banks power package on it when it was fairly new they used it as a rodeo truck towing a big horse trailer, we converted it into a rollback towtruck and put a edge juice with att for the safty features it makes a 400mi round trip towing 1-2 cars/truck one on the bed and one on the trailer it also gets used locally we put injectors in it about 10-20k ago and had something minor fixed in the transmission when we got it 6th gear would grind going in and its due for some balljoints for the first time since we have owned it.I guess there a common problem with balljoints on the newer dodges but we have not had an issue till now and if you live in montana you know how our roads are smooth as glass:rof trying to talk my dad into puting twins on it cuz egts are pretty high with a big load on it well the truck weighs 11500 by itself

when my dad first started his towing/salvage/repair buisness he bought a brandnew 1990reg cab cummins put a wrecker unit on it and went to work the truck now has over a 1.3million on it, it dont get driven much anymore except on recoverys because it dont matter beating on it up mountian roads cheap and easy to fix. its on its origional engine its had a ton of other replacement parts. the difference between this truck and say a commuter truck this truck weighs 10k+lbs and it tows a car/truck atleast 1 way or bothways there and back so this truck was actually worked its whole life and if you saw the truck you would agree:gearjamin we call it the 90 its the founder of my dads company and it will never leave the family.this truck is the most powerfull stock ve pump truck ive ever driven and ive driven alot of them between our dealership and salvage yard we have had alot of them.
The injectors are woreout and its smokes pretty good at wot because of it and the motor turns over pretty fast when starting it because of the miles and for some reason it has always reved really fast for a cummins

replace parts


turbo
2 headgaskets
couple transmission
couple frontends
couple rearends
2 drivers side doors
fenders hood hit a deer
frame welded a couple times
turbo



the cummins is great i will never own anything differnt i was also born into a mopar family. the dmax is a great engine i give credit where it is due but nothing works like a good ol cummins
 

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My freinds 6.7 blew a head gasket. haha, I think that all the diesels are good engines each have their goods and bads. I like all of them to a extent but im a D-Max guy!!
 

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Honestly as good as the DMAX is, I don't think I would put down the Cummins for reliability. And bringing up cummins injector issues is kinda silly considering the first couple years of the dmax and the insane trouble they had?!

The Dmax is solid, makes lots of power easy etc., the Allison stomps all the RE trannies, and the truck itself is probably better quality... but the Cummins overall does have a solid record, and for good reason, and it IS easier to work on which is nice... They are both very good no doubt...
 

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ive had both, an 03 cumapart and i have a 03 dmax. the dmax by far is a better truck an motor!!!!!!! my buddy 07 5.9 cummins went out at 39,xxx miles an cost him @ 10,000 = junk
 

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ive had both, an 03 cumapart and i have a 03 dmax. the dmax by far is a better truck an motor!!!!!!! my buddy 07 5.9 cummins went out at 39,xxx miles an cost him @ 10,000 = junk
my buddys bent a rod sooooo? ive never seen a cummins bend a rod, as far as true work trucks go ive never seen a d-max towtruck not because of the engine and transmission its, the suspension is junk. And the transmissions in the ram and chevy are junk they dont hold much power stock compared to fords!. There are guys with the 68rfe that are makeing 450+hp with more than 20k+mi holding up fine to me thats pretty good comeing from dodge:D.They all have problems dodges make good work trucks and chevys make good race trucks, ecept for arron nicks 6.7 cummins with s480 single flux 3.5s stg2 d-max cp3 with stocker and built trans and thats it ran 11.6 defueling he left speed limiter on 120mph and its virtually smokeless it puts out a puff of smoke when it takes off. the video posted below is arrons truck vs blacksdiesel race truck same setup except sidemount intake ported head and cam and its a 5.9 to me i would say the 6.7s have passed the 5.9s in power up to a certian exstent just need more time.


left is 5.9 right is 6.7 look at how they smoke

 

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My ears! The music! My ears!:eek:

Thank goodness for loud ass Cummins to drown out that music at the end.

Since the rods/pistons are so much bigger in an I-6 diesel, I would think the inertial energy from an overspeed situation (very high rpm) would spin bearings, break wrist pins, exit blocks, etc much more so than in a V8 configuration. On that same token, and could see an I-6 (see 12valve) running all day, every day within normal rpm range, and running much more efficiently than a V8. In fact, they do.

It's all in what you want and do. You take an Allison trans, a Cummins 5.9 12v and the Ford interior/tow mirrors and put it on whatever platform you want. That equals a very efficient, reliable and comfortable truck. Wouldn't try drag racing it, but could tow for many miles and be happy.
 
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