bad vibrations.

I have a 2007 Dodge 2500 with a 5.9 Cummins.
it has 129,000 miles on it. I only put the last 9000 on it.

I have worked on my own cars, truck, and Harleys.
but, this is my first diesel truck.

my truck has a vibration in it. I can't find out what it may be.
so I am hoping some one out there can help.

at 2000 rpm it starts and goes up as the rmp dose.
when I shift it goes down and starts over.

I feel it more in the floor than any where.

I don't feel it in the 4x4 shifter.

very little in the steering wheel.

It is not the drive line, or rear ends, that would go up and down with speed not RMP.

I checked my pipe to see if it was rubbing some thing, it is not(I don't think the rubber hangers can get hard)

all oil temps are running good.

I was told it may be the injectors, but it idles smooth.

I was told it mite be the fuel filter, I have all ways thought when the plugged it would shout down.

it don't smoke any more than it should.

it cant be tires, that would be speed also.

I thought it may be a motor mount, but that would make a noise when you put it in gear.

I do think it is worse when it is pulling a load.



any one got any ideas????

 

Check the U-joints; when were they last serviced/replaced?

Has the driveshaft ever been removed? It could be out of balance.

Check the driveshaft; is it the one piece or two piece? Most folks that have an RPM based vibration (goes up and down with shifts and changes in RPM) comes from the two piece driveshaft. Upgrading to the one piece shaft is the fix.





-Kris

 

Kris,
thanks for the reply.
I do have a one piece drive line and it is in good shape.
if the vibration was coming from it, it would be speed not RPM that made the vibration.
because the drive line don't slow when the rpm drops at a shift.
Gary

 

Is the vibration there with the trans in park/neutral and the truck sitting still? If the vibration is still there without the truck moving, then the prob would almost have to be engine related. Plugged fuel filter (yes it will run, just not well as the fuel can't keep up with engine demands) or ya got an injector going south.

If the vibration is only there with the truck going down the road, I'd be looking real hard at the drive-line and/or tires.

BTW. Have you actually pulled the drive-shaft(s) out and physically inspected the u-joints? When these joints fail, they usually don't get all sloppy and loose. Instead, they dry out and the bodies fuse to the caps, This keeps the joints from flexing and causes all kinds of issues from slight vibrations to destroyed transmissions/t-cases or axle pinion bearings.

 

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I changed the fuel filter today before I got your note. I was thinking as you said about it or the injectors. I have not had a chance to drive it yet.
I did not try to see if it had the vibration setting still. it only dose it at 2000 to 2500 rpm, I don't think thats to high is it? one guy did say that all diesel's have a vibration in them. but, I don't think this is the norm.
I have not pulled the drive line.
the reason I am thinking it is not drive line or the pinion bearings is that I have NO vibration in the 4x4 shifter at all. also after driving it the other day I got under it and noting was hotter than it should have been.

I ran a full set of Gauge's as well as the ones on my Bully Dog, they all show good to go.(even the fuel pressure is ok)

I don't know when or even if there has been any drive line work done on it... so I will redo the u joints any ways..
thanks for your help.
Gary

if you want to see the truck and what I have done to it, this may work... http://www.facebook.com/video/?id=100001762401076