Drivetrain vibration.

[Scarylarry]

Hey folk, I've always gotten very educated advice from you all so I hope someone can help. Got a 14/1500 2WD, 125k 5.7 Body lift 3 " Airbags in coils and 30lbs or so in them. I'm a master ASE and this one has me baffled. I first noticed when I kicked her in the but, I got a slight shudder. Didn't do that too often blew it off. Got so I could feel it under mild accel so I replaced all u joints and center bearing. NO HELP. I just got back from Tampa and had both shafts ballanced. NO HELP. It's getting steadly worse, All rear axel torque rod bushings are tight , tires are ballenced and shocks are fine. Trans output bushing is fine as is axel input, No play. Both engine and trans mounts are tight. It is felt in the steering wheel as well as the seat. Entire truck is shuddering under a load and heaven forbid ya try to tow a travel trailer, Went to Arkansas last month and shook the begeebies out of every one. I am really desperate at this point and don't believe a dealership tech can help more than an experienced Ram enthusiast. Tankz for you time.

 

[2003F350]

Any codes present, either active or stored?

Wheel bearings? Warped brake rotors? Engine misfire condition? TC bolts all tight? Flex plate balanced?

Vibrations are a devil to track down once you exhaust all the 'common' causes.

 

[Scarylarry]

N o codes, Bolts in flex plate would make noise, wheel brngs would be loose and or noisy, Foots not on brake for rotors,, flex plate HMMM, maby but vibration goes away all together no matter what speed when not trying to accelerate. Yea I grabbing at straws now also. Thanks for you feedback (2) It's greatly appreciated.

 

[2003F350]

In my experience, I have had TC bolts make no noise, I've had wheel bearings that were silent despite being bad and causing vibrations, and with a warped rotor you wouldn't necessarily need to be on the brakes - a warped rotor forcing a brake caliper back and forth will cause a vibration. However if it goes away when not accelerating I would say not brakes or bearings.

Since it goes away essentially when coasting or steady-state, I would suggest it is a misfire condition. If nothing shows up while watching live data then I guess I'm stumped as well.

 

[turkeybird56]

Here is a straw: Could you have a Loose Motor Mount/Trans Mount that is moving and shifting/torqueing when under power, getting all parts out of line and a shudder? Years ago had an ole Chevy built up, with a bad motor mount. That 396 under WOT would shift up and the poundings was bad. Stayed that way till I got a new motor mount in there, but then I was a kid and we all had no money. Just a thought from the past.

 

[Scarylarry]

In my experience, I have had TC bolts make no noise, I've had wheel bearings that were silent despite being bad and causing vibrations, and with a warped rotor you wouldn't necessarily need to be on the brakes - a warped rotor forcing a brake caliper back and forth will cause a vibration. However if it goes away when not accelerating I would say not brakes or bearings.

Since it goes away essentially when coasting or steady-state, I would suggest it is a misfire condition. If nothing shows up while watching live data then I guess I'm stumped as well.

Yea, I turned off the MDS today out of desperation......no help. Tankz.

 

[Scarylarry]

Here is a straw: Could you have a Loose Motor Mount/Trans Mount that is moving and shifting/torqueing when under power, getting all parts out of line and a shudder? Years ago had an ole Chevy built up, with a bad motor mount. That 396 under WOT would shift up and the poundings was bad. Stayed that way till I got a new motor mount in there, but then I was a kid and we all had no money. Just a thought from the past.

Yea, good thought. I put a jack under the trans and motor w/no movement. Tankz.

 

[18CrewDually]

You need a good scanner/monitor to check pending codes.
If no codes I'd monitor trans input and output speeds to see if the torque converter clutch is slipping when locked up under accel and it is shuttering.
I've also seen trucks act as you described when there is a bad coil, plug, or injector. Under heavy load the pressures can make a plug not function, the heat can make a coil break up, and poor atomization or lack of fuel from a bad injector can cause misfires that feel like shutters. But usually after it does it enough it should throw a lean or rich misfire code.

 

[Scarylarry]

haden't thought of that .so under a load ..say in 6th or 7th. The input and outputs should be EXACTLY the same or is a certain ammt of slip OK. I'm gonna set the scanner up and get some data. Is it ok to contact u. later???

 

[Scarylarry]

Out of 122 lines of data I cant find anything Trans related except Reverse soledoid????? I've got a Launch 129x. Am I missing something???