6.7L Engine Problems??

[HBarlow]

After a brief rush of problems reported in the TDR forums 2 or 3 months ago I've not read or heard of anyone having any problems with the new 6. 7L engines, '07. 5 or '08.



Are the problems corrected? If so, we are seeing amazing results from Cummins and Dodge. This is a completely new engine and automatic transmission combination introduced along with the equipment required to meet very restrictive new '07 federal emissions requirements AND, software and hardware changes to meet the 2010 emissions requirements and we've seen very few problems.



The problems we've seen reported with early '07. 5 Rams have been very few on a percentage of units sold and operating basis and I have not seen even one reported problem with an '08.



Can anyone dispute this? Is anyone experiencing problems?



My own '08 cab and chassis has 1200 miles on it. I put 400 highway miles on it the day I bought it early in March and since then it has acquired another 800 miles of short trips, start and stop driving around town. I have no idea if it has ever performed a regeneration cycle and have seen no codes. My overhead shows 14. 5 mpg driving around town.



Please post if you have problems to report.

 

[Dan Simmonds]

My '07. 5 with 6-speed manual has been upwards of 15-16 MPG now that the software recall was done & turbo & oxygen sensor replaced. This mileage was unheard of on my truck a few months back.



Pulling my 14,000 LB flatbed will bring it down to 12-13 MPG, but even so, the towing mileage has also improved 4-5 MPG over what it was.



Just flipped to 28,000 miles last week.



The stalling has also gone away it seems - truck used to stall for no reason just at idle when the truck was new.



On a different subject, the oil still becomes jet black just 10 miles after an oil change. So I change the oil about every 5,000 because of it.

 

[AllianceDiesel]

the biggest problem with the 6. 7l is people idleing it and causing the cylinder temps to drop which doesn't allow the fuel to completly burn and that fuel goes into the emmissions b. s.



On your oil, its gonna do that no matter what, the color of the oil has nothing to do with the condition of the oil

 

[HBarlow]

the biggest problem with the 6. 7l is people idleing it and causing the cylinder temps to drop which doesn't allow the fuel to completly burn and that fuel goes into the emmissions b. s.



On your oil, its gonna do that no matter what, the color of the oil has nothing to do with the condition of the oil

I agree with MOPARTECH. Both of my previous Dodge-Cummins immediately blackened the oil after a fresh oil change. I ran both of them on a 10,000 mile oil change interval using basic old Shell Rotella and Fleetguard filters purchased from Genos. The '01, with 343,000 miles belongs to my son-in-law now and is used by new-hire job superintendents in his construction company. The '06 was recently traded with 228,000 miles for a new one.

 

[Dan Simmonds]

Yes, understood on both counts mopartech & Harvey.



I was comparing the oil color to that in my '07 5. 9L - which will go much longer than the 6. 7 before the oil turns a hard black. Just an observation I've made between the two stock engines.



If the idle time is really that much of an issue now with the 6. 7, I would have to think an addendum is in order for the owner's book that is supplied with the truck, to announce this to those who are accustomed to prolonged idle time with their Cummins pickup.



It's really for the benefit of the owners as well as the dealers, DC, etc to broadcast this issue of idle time right at the dealer level without having to have owners rely on feedback from other owners to learn this from once a problem has resulted because of it.

 

[AllianceDiesel]

its says not to idle your truck for prolonged times in your owners manual and there is suppose to be a dvd out that talks about it, that all the 6. 7l owners should get

 

[Dan Simmonds]

You're right - the CD / DVD does make it very clear about the effects of prolonged idle time - I had forgotten about the CD.



My CD / DVD came in the mail about a month ago.



Unfortunatly though, for a lot of guys like me, it was a matter of "too little too late".



This sort of info needs to be in the buyers hands and/or eyesight, etc before the purchase is made, so they know exactly what they are getting into.

 

[AllianceDiesel]

yep I completly agree but salesman aren't smart enough to even know what idle time is, if you do idle your truck, every once in a while drive it like you stole it, high idle times are hard on all common rail trucks not just the 6. 7

 

[gmonroe]

My 07. 5 6. 7 idles a long time, up to 1. 5 hours on some emergency calls. However, running it at 105 to calls 2-3 times a week seems to keep it clean... . never saw any warning of any kind. At work it runs around 115 acre campus at 5-15 mph all day, but running home at 75 for 10 minutes seems to keep it clear as well.

 

[jtwcummins]

The problem is what is 'prolonged period'. I never idled my 97 more than a few minutes, less than 5, unless I reved to about 1200 rpm. Even then about 5 min tops. Do the same with 08 except set high idle using cruise control.



So how long would be considered to long?

 

[Dan Simmonds]

I too am curious where the line is drawn regarding acceptable idle and extended idle.



This makes me remember when I would idle a newer 3406E Cat engine for 6-8 hours at a time on the road, it was always recommended to adjust the in-cab electronic idle control (set using the cruise control) up to 1000 RPM or so for the duration of the idle, which gave increased oil pressure, etc. On a pickup, there isn't an easy way to do this without a mod.



Dan

 

[HBarlow]

I too am curious where the line is drawn regarding acceptable idle and extended idle.



This makes me remember when I would idle a newer 3406E Cat engine for 6-8 hours at a time on the road, it was always recommended to adjust the in-cab electronic idle control (set using the cruise control) up to 1000 RPM or so for the duration of the idle, which gave increased oil pressure, etc. On a pickup, there isn't an easy way to do this without a mod.



Dan

Your signature doesn't identify what year Dodge-Cummins you own so I can't say for sure your truck has the feature but all the trucks of the last several years with OEM cruise control, '05 and up for sure, are programmed from the factory for in cab adjustable fast idle just like the Cat engine you described above. All it takes is for the dealer to attach a scan tool and enable the fast idle.

 

[Dan Simmonds]

I see my signature disappeared from earlier posts...



I've got two company trucks now... an '07 6. 7 (with no cruise) and an '07 5. 9 (with cruise). Both are dually 6-speed manuals.



The 6. 7L has 28,000 miles and is totally stock - the 5. 9L has under 50 miles on it, and the only addition so far is the Pacbrake & the B&W turnover gooseneck ball.



Heck - I didn't even know the cruise control equipped trucks had the adjustable idle already there. I wonder if it can be turned on with the Smarty programmer as well?

 

[RideSlow2004]

running it at 105 to calls 2-3 times a week seems to keep it clean.....

Just have to ask, RPM at that speed?



I have just 4,900 miles, have not had a chance to stretch the legs on this one yet.

 

[hwebster]

08 6.7l

Well 8,000+ miles and touch wood no issues...



Just took a 900 mile trip and heading out the computer was ~13mpg, but over the next 400 miles or so it creeped up to 16+! Very pleased...



DPF was getting close to 30% based on my insight, dropped to 12!



So Far So Good... . and I love climbing big hills!!!



H

 

[AllianceDiesel]

Like I said earlier it is only bad to idle the common rail trucks, it has to do something with the engine is so efficient at cooling the cylinder at idle that the fuel doesn't completly burn, thats why they have the high idle feature on the auto's only (too much liability on the manuals)

 

[JimLarsen]

My 07. 5 has 12000 miles now. I have had one 400 mile run that returned 18. 4 miles to the gallon, I was WOWED. Most times I run about 13 to 15 mpg. Love the truck so far. What about fuel additives? I am using Standyne now? Should I keep using it? Have heard both ways, Yes use it. No don't use it.

 

[AllianceDiesel]

yep standyne is one of the best ones out there, I know some people run a good quality 2-stroke oil but don't know if anybody is running them in the 6. 7's yet.

 

[JimLarsen]

Thanks for the reply Mopartech. Has the magazine had any write up on if should be using a fuel additive? I have just ordered the Turbo Register Diesel so I don't know if anyone has written about additives.

 

[gmonroe]

105 on a six speed manual runs right at 3,000, I will check what rear end I have... .