98 Ram 1500 sport vibration issue?

[slider11111]

Hey guys. I have a 98 Ram 1500 4x4 5.9 with OD tranny. The truck has about 230,000 care free miles. Most of the front end was redone last year. Ball joints, track bar,tie rod ends,bushings yada yada yada. The truck drives like new. I had new tires put on a couple months ago. The last couple weeks I have been noticing a vibration at highway speeds. It starts when the highway changes say from concrete to asphalt. The steering wheel does not vibrate. If I let off the gas and then press on the gas again the vibration stops. I can also turn off the Over Drive by pressing the button and the vibration stops. It does it either in or out of OD. What is the problem?

 

[leadrofthepak]

Could be a rear drive shaft u-joint failing.

 

[slider11111]

I took it to the driveline shop today. They checked it out and are going to replace the two rear U-joints.

 

[slider11111]

I had both rear U-joints replaced this A.M. and the vibration is still there. Today I got it to do it at 60 mph and shifted into neutral and it stops vibrating. The same as using the gas pedal or shifting out of Over Drive?

 

[dodge dude94]

Putting it in neutral takes the load off the engine so it can't allow you to see if you have a miss. I'd try it again at that speed, in D but having turned OD off.

 

[slider11111]

It does it in or out of Overdrive.

 

[dodge dude94]

So regardless of engine speed?

I re-read your original post and you stated you can turn OD off and it goes away. That indicates a misfire to me. Please confirm.

 

[slider11111]

Yes when it's vibrating in overdrive I can turn of the overdrive by pushing the button and the vibration stops.

 

[rebel89820]

I have a pinion bearing about to stb... and it kinda does the same thing... bad vibration at 40-70mph, but if I let off gas or keep a constant gentle acceleration it stops. Only reason I'm thinking pinion bearing is its had a leak forever and I forgot to fill it on last hi way trip. Filled it after about 4 Miles when vibe was more pronounced and it quit. New parts here, will install this weekend.

Sent from my DROID RAZR

 

[Merc225hp]

What DD94 posted, time for a comp and or leakdown test.

 

[dodge dude94]

Yes when it's vibrating in overdrive I can turn of the overdrive by pushing the button and the vibration stops.

that's a misfire.

What DD94 posted, time for a comp and or leakdown test.

If you haven't replaced the plugs, wires and done the wire route per the TSB....I agree with mark.

 

[slider11111]

I just checked for play in the Pinion bearing. Seems fine. I had new seals put in the rear end by the differential shop 18 months ago and they said everything else looks great. I also just pulled all the plugs (6 months old) they are all normal.

 

[slider11111]

I have never replaced the wires or done the wire route per the TSB.

 

[dodge dude94]

TSB 18-48-98

 

[slider11111]

I will replace and reroute the wires next.

 

[slider11111]

OK I replaced and rerouted the wires per the TSB. I also replaced the rotor and cap. It runs smoother and no dieseling going up a hill under hard acceleration now.The truck no longer vibrates at 40mph but it still vibrates at 60mph?

 

[slider11111]

I took a mechanic for a ride today. He says it is in the drive train somewhere? He recommended I go to a transmission shop and have the transmission and transfer case checked for metal in the pan.
I then went to a Transmission shop and they think most likely the valve body needs rebuilt. Or it might be the torque converter. They are going to drive it Friday.

 

[jbmobbs]

If all else fails.....did a friend, girlfriend, or wife leave a vibrator under your seat?

 

[slider11111]

I'll check!!!............lol

 

[slider11111]

The Transmission shop took the truck for a drive with their code reader connected today. It did show an error code although the check engine light does not come on. The error confirmed their suspicions. The valve body in the transmission needs to be rebuilt. There could also be a problem with the converter? He said either way they would rebuild the valve body in the transmission. And once that's done it's just a matter of time before the converter needs to be replaced. The cost of the valve body rebuild will be $300 to $325. I have an appointment for June 10.