2004 Cummins

[crashz]

Some punk kids threw a rock through my windshield on Saturday, stranding me at my parents. I left my truck at my parents this week and borrowed my fathers new Dodge 2500 CTD. This thing is great! Its a 4x4, Laramie,Off Road package. You name it!

My question for you Cummins gurus is this: The truck runs beautiful and very smooth. But often I hear what sounds like valve clatter and around 65 -70 mph it vibrates pretty significantly. Any reason for concern?

BTW - its the newer 600 ft-lb version. Only 4500 miles.

[scfall]

I just drove my buddies new 3500 CTD home from the UP and noticed the same vibe, He said he never really noticed it till I questioned it. His only has 3100 miles on it. Also what kind of milage is your dad getting? his is running around 15.


Scott:burnout

[crashz]

Yea - 15 mpg is the norm so far. I assume it will get better when it breaks in. Rumor has it that the Cummins doesn't really break in until about 20,000 miles.

Do the valves need adjusting? The more I pay attention to it, the more concerned I'm getting. Also, its more noticable when the truck is warmed up to temp. When cold it is still present, but muffled.

[wyldman]

It probably needs a reflash.There is an update available to fix the mileage problems,and the symptoms you describe.It's an injection timing issue.The mileage will continue to get better over time,even well past 20,000.

No need to adjust the valves.

[TLS]

Sure it's not driveline vibration?

There are several cases of this on the new 555 and 600 Dodges.

[John DiMartino]

In addition to what Wyldman said, pulling a trailer (esp a heavy one)really helps speed up the break in time. If you dont pull a trailer it could easily take over 50000 miles to fully break the cummins in. I got my 2000 used at 48000 and it hadnt ever towed,the mileage wasnt great.After 7000 miles are hard use,and heavy towing you could feel the engine got stronger.picked up some MPG,and the blowby bottle wasnt nearly as full of oil. The Cummins is of a very heavy duty design and was meant to work under a heavy load ,more than our empty pickups can put on them,thats why the trailer helps so much.

[cat320]

OK so now we know they are all not perfect:) I have a cummings in one of my machines good engine well i had all three untill i sold my chevy lol

[crashz]

Thanks for the good info guys! I'm glad its nothing to serious.

The vibration is definately driveline related. Feels like the 4wd is always engaged. But up to 55mph and after 75 its nice and smooth.

Gonna miss this thing when I give it back. :( But when I do I 'll have my father take it to his dealer for the reflash and vibration issue. Thanks again!

[wyldman]

The reflash has solved the vibration on some trucks.The current injection sequence causes a shudder that can be felt right through the drivetrain.Do the reflash first,and then have them look at the vibration if the reflash doesn't solve it.

[scfall]

I'll have to tell my friend about the reflash also. Funny the dealer does'nt do that automaticly before they sell them. He's very loyal to this dealer and has bought 7 Cummings from them in the last 2 years.

Scott:burnout

[crashz]

Update:

The dealer that sold the truck and in fact all the dealers in Berkshire County deny any knowledge of the TSB. So I took the truck for the week and brought it to Burlington Dodge for the TSB reflash. They quickly took care of it and the tech even showed me how they did it. Gotta recommend these guys for any service, they are great to deal with.

The tech took it for a test drive and found the vibration. He feels its either an unbalanced shaft or a bad u joint in the frontend. The truck will go back in on Friday for that.

But as for the reflash: The truck is like a big diesel corvette now! Wicked smooth, no clatter at all, and even more powerful. So much more quiet and responsive.

If anyone has a similar model and has any doubts about the performance, have it checked and reflashed if applicable.

[wyldman]

When they look at it for the vibration,just have them pull the front driveshaft (from TC to diff),and test drive.It will probably be gone.They had some problems with bad front driveshafts.

[crashz]

Thanks Chris!

The service tech hinted that it was probably a driveshaft issue, but I thought the driveshaft won't turn unless the axle disconnect is engaged. Right?

Does the front shaft always turn?

[wyldman]

They no longer use a CAD on the front axle,so it turns all the time.

[Joey D]

Wasn't there another vibration coming from the power steering pump hose? I recall an issue with it which they solved with a fitting over the hose.

[Lawngodfather]

Originally posted by John DiMartino
In addition to what Wyldman said, pulling a trailer (esp a heavy one)really helps speed up the break in time. If you dont pull a trailer it could easily take over 50000 miles to fully break the cummins in. I got my 2000 used at 48000 and it hadnt ever towed,the mileage wasnt great.After 7000 miles are hard use,and heavy towing you could feel the engine got stronger.picked up some MPG,and the blowby bottle wasnt nearly as full of oil. The Cummins is of a very heavy duty design and was meant to work under a heavy load ,more than our empty pickups can put on them,thats why the trailer helps so much. I took Johns advice, drive mine hard and towed some heavy trailers plus plowed many times with it, also drove 200 miles with plow and spreader late Dec.

The truck only gets better. Got about 27,000 miles right now. MPG went up 1.3 points I am over 18mpg in the city with 4:10

Hauling, the thing is a monster, better keep a good watch on the speedo on the highway, many times I cought myself hitting 80mph with a 8-10,000 trailer behind it.

[John DiMartino]

Theres a new TSB out this week on the front axle vibration.It involves balancing the front driveshaft on affected trucks.