I'm running an all stock suspension on my truck, with non-aggressive M&S Cooper tires for the snow and the stock Michelin's for the summer. I have experienced a vibration that I can feel across the floor board and it resonates right up the gas pedal. Have taken the issue up with the local dealer a couple of times and they can't seem to find anything they say is "out of the ordinary". They did re-adjust the exhaust one time (it was touching the cross member) and said that should take care of it, ....it didn't.
This is my first cummins and I don't know if a slight vibration is normal???? I have had the same issue on both my summer tires and my winter tires.
Anyone else have vibration issues??? It's an 04 with 30k miles.

 

I just read an earlier thread, I don't think it is u-joint issue since I noticed it and it first went to the dealer with less than 10,000 miles. I don't feel it through the steering wheel, just through the floor and gas pedal.

 

At what speed? My '03 has a vibration at 69-73mph. Mine is definately speed related, not rpm.

The dealer says "they all do that"

 

Could be your front Hub Bearings or front axle u-joints going out. Could also be your tires not being balance properly or installed in the same directional location when they are changed out. Or are the tires on separate rims and marked prior to removal?

I notice you said it has been going on since the truck had 10,000 miles on it and do not believe it could be a u-joint. Believe me, it might still be a bad u-joint.
I have over 32,000 miles on mine and just had my truck's center carrier bearing u-joint go out on a trip to South Dakota. Although, all my other trucks did not have their first u-joint problems until well over 100,000 miles on the odometer. Which brings me to the conclusion that Dodge is using cheap imported Chinese parts, which fail earlier than expected. If you do not believe me then do I search on these boards and on other forums. I would crawl under your truck and look for any slack in any joint and keep an eye on it.

Could also be your carrier bearing. I just do not remember, but I thought I saw a TSB out for the 2004 to have the carrier bearing shimed. I will have to look.

Shawn

 

Check out this tread on this forum. He went to the works to find the shake and still had the problem. It ended up being bad U-joints that felt fine when inspecting them, but were toasted when he pull the drive line.

https://www.dieseltruckresource.com/...d.php?t=148181

Shawn

 

Sometimes there is mud and other crap in your rims, gets really bad on the stock rims, that builds up and you take it to the car wash and dont get it all out. Then you shake all the way down the road!!! Imbalances the wheels really bad. I drive through mud all day and have to take a screwdriver in there to get it all out.
This might be a little obvious, but thought I would through it in.

 

I have alays had a slight vibration that occurs right when taking off from a stop. It wiggles a little bit from about 3 -5 mph, and then goes away. I have tried to get the dealership to fix it, but they also said "they all do that" beacuse of such a long driveshaft. (3500 DRW quad cab, long bed)
I can see the carrier bearing wiggle from looking between the bed and cab, but the dealership can't see it??

 

Read through all of this and I'm sure its what you have going on with your truck. I finally talked with a Dodge mech just last week that told me what the problem is.
https://www.dieseltruckresource.com/...0mph+vibration