Commonrail Cummins reliability

Darwin

Explorer
I am in the market for a new truck and I am curious about the reliability of the newer 3rd gen Cummins trucks. I currently own a 12 valve Cummins, and I am really familiar with this motor and truck. I like the simple mechanics of it and trust myself to fix anything that goes wrong with it. However, finding a 12 valve that hasn't been beat to death, has decent paint, doesn't have tow mirrors and is priced fairly is not an easy task. This has me thinking about a newer 3rd gen commonrail. It would be nice to have something with newer interior, paint that isn't peeling, and 4 doors would be nice. I would probably be looking at a 1 ton since I am also looking at getting a slide in camper. Also, this truck would be driven south of the border so reliability is a pretty big deal to me. Any opinions/advice on what to do or look for? I have heard the 03 and 04's tend to be more reliable than the later years.

Should I stick to looking for an old mechanical 12 valve or expand and consider a commonrail?
 

Buliwyf

Viking with a Hammer
"BEEEP BEEP BEEP" [SEE DEALER NOW]
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That's the sound and error message that replaced the awesome racket of the 6BT5.9. Nowhere near as reliable as the older Dodges. It's about the same quality as the GM Duramax and Ford 7.3L if you tow heavy with it. They hate unloaded travel. Our fleet ones spaz out. And a friend of mine had one that would sit in regen forever getting a whopping 5mpg unloaded.
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Don't believe the hype and the giant "C" sticker guys. It's got as many problems as the other American diesels. But if you do your homework and use the truck appropriately, you can mitigate that risk. I just switched to gas engines until the American diesels get their acts back together.
 

Darwin

Explorer
Interesting points, I would be looking at 03 and 04 which I hear do not melt down at easily at the newer ones. I would also delete all the possible emissions equipment.
 

Buliwyf

Viking with a Hammer
We tried straight exhaust and an Edge tuner. Now his truck is really miffed. Not sure how we'll get the ECM reprogrammed to quit screaming alarms.
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I'm sure that towing, or at least some 80+mph action should keep them cleaned out ok. I have another dimmer than normal friend that bought a fully loaded '07 for his personal use. He owned a lawncare company. The truck towed heavy, but never faster than 35mph. And never, ever saw the freeway. So it was stuck in permanent regen as well. Dodge tech: "You have to use them as intended."
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Throttle tip in was also really aggressive on the Edge programmed truck. I wonder if the programmer messed that up, or if it was a bad throttle pedal. Would've been a pain in the snow. We also put the EGT sender preturbo, like it's supposed to be. Maybe the programmer was supposed to have that mounted after turbo because it prealarms at a too low EGT.
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Your best bet is to find the custom tuned Dodge guys on one of those forums. From what I've seen so far, the Cummins ECM doesn't like people messing with it or it's emmisions controls. Maks me feel better about my trusty "Chitty Chitty Rattle" Ford 5.4L.
 
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iluv83vettes

Adventurer
My roommate from college has an early 07 (no DPF) with a 6 speed. It has a little over 100k on it. He doesn't have a chip, but he does have a new intake (not just a filter, but everything pre and post turbo. He also has an aero turbo muffler but the rest of the exhaust is stock. The only thing he has replaced is the clutch and he got that done at like 95K.
 

verdesardog

Explorer
I love my 06 CTD. It did trash two injectors shortly after I got it with about 80k miles on it. I have no idea how the original owner maintained it.

I now put diesel kleen and 2 stroke oil it the tank at every fill up. 1:2 DK to oil, 1oz per gallon of fuel. No problems since. My truck is stock except for what's in my sig.....
 

plainjaneFJC

Deplorable
The newest Dodge that I owned that was good was the 06 5.9, my 07 6.7 was a pos. Now my 2011 duramax is leaking oil from the rear of the engine. I can't win.
 

Rhinopkc

New member
I have an 07.5 Mega Cab 3500 with the 6.7 diesel, I have all emissions deleted and my truck has been super reliable. This is my second reliable 6.7, the first fell victim to a rollover while parked in the desert. I spend much of my recreation time in the Arizona desert, if my truck wasn't reliable, I wouldn't bring it along.
 

Regcabguy

Oil eater.
I've got 54K on mine without a trip to the dealer aside from the K01 reflash that promptly killed my ecm. New ecm on Dodge. The owner of a Dodge garage I use just replaced his injectors and bj's at 180K on his '03 HO. Preventive maintenance,moderate power increases and extra filtration work wonders.
 

deserteagle56

Adventurer
I believe any of the 5.9 engines are very reliable. If you go to the 6.7 then you'll have to put up with the problems (as mentioned above) with the new pollution controls, regeneration, etc. Most complaints I hear from owners of the pre-6.7 vehicles are more in the line of ball joints, heater controls, things like that. No complaints about the engine. My Ram's 5.9 has had zero issues.
 

redthies

Renaissance Redneck
I assume you are mainly interested in 5.9s. The 6.7s are far more complicated, and thus problematic (dpf, regen etc). The '03 and early '04s are arguably the most reliable, and fuel efficient. The 305/555 engines found in the first year and a half of 3rd gens only have two injection events per ignition, whereas '04.5 to early '07s have a third injection event. This lowers fuel economy, and causes a hotter burn, which has on occaision, led to melted pistons. This third event is also what makes them a lot quieter. I have driven an '03 and owned an '05. There is a noticeable power difference, but if I were shopping now, I would look for a '03-'04.

Another option, would be finding a cheap 3rd gen and putting a12v in it. Best of both worlds. I saw a low mile theft recovery '08 with no drive train going for around $10k in Az. It was mint, and with a 12v, would have been awesome
 
Hi. New here. 08 Dodge 3500 6.7. Owned since new. Stock, gobs of power, gasser mileage, 10 towing, 14 highway. Deleted dpf and egr at ~36,000 km after a 6mpg tank one winter (always in regen). Lots of soot in the intake. Since then, 50% better mileage and no issues. Expect the 6.7 to far outlast the dodge transmission, body, chassis.
 

Darwin

Explorer
I assume you are mainly interested in 5.9s. The 6.7s are far more complicated, and thus problematic (dpf, regen etc). The '03 and early '04s are arguably the most reliable, and fuel efficient. The 305/555 engines found in the first year and a half of 3rd gens only have two injection events per ignition, whereas '04.5 to early '07s have a third injection event. This lowers fuel economy, and causes a hotter burn, which has on occaision, led to melted pistons. This third event is also what makes them a lot quieter. I have driven an '03 and owned an '05. There is a noticeable power difference, but if I were shopping now, I would look for a '03-'04.
I am looking at 03's and 04's for just the reasons you outlined. The thing is though the common rail makes me a little nervous, I am afraid I will be disappointed on the reliability front, spend the money only to have it break down. I know about the injectors and the prices, I dont mind buying a set of injectors if I get 100 to 150k service life out of them. Having a truck with a bit nicer interior than my 12 valve, paint that isn't fading, a dash that isn't cracked is pretty appealing. That said, I saw a 98 12 valve dually in nice condition the other day but they want the same price for it as a 2003 dually in pristine cond. with the same amount of miles. It's damn near impossible these days to find an unmolested 12 valve for a fair price. I am willing to pay a fair price, but what some people are asking is just plain crazy. I know good deals exist, but the the whole deal has me thinking about a commonrail. 305 hp in stock form with a 6 speed is pretty temping.

Another option, would be finding a cheap 3rd gen and putting a12v in it. Best of both worlds. I saw a low mile theft recovery '08 with no drive train going for around $10k in Az. It was mint, and with a 12v, would have been awesome
I have given this idea some thought too. A newer truck with the ultimate motor. What I wonder though is if I go common rail and the motor blows would I still want to stuff a 12 valve in it? Or will I be so happy with the common rail that I simply rebuild it and put it back in?
 

bknudtsen

Expedition Leader
I have given this idea some thought too. A newer truck with the ultimate motor. What I wonder though is if I go common rail and the motor blows would I still want to stuff a 12 valve in it? Or will I be so happy with the common rail that I simply rebuild it and put it back in?

In most states, putting a motor in a vehicle that is older than the model year of the vehicle is a big NO NO. Just a thought, if that kinda thing concerns you.
 

redthies

Renaissance Redneck
I know exactly what you mean. I have that very same '98 12v dually in nice condition. I find myself looking at '03-'04 duallies on Cumminsforum all the time. I absolutely love my truck, but I sometimes think a 3rd gen would be a bit less fatiguing on long hauls. My truck is very very "truck". Two weeks ago I did back to back 10 hour drives with the camper on in a huge storm (75 mph wind gusts, trees falling on rd and hitting camper etc) and found it a bit much. Mind you, I'm not sure I would have been any less tired in a brand new truck with every comfort option.
 

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