Intermittent Rough Ride/Vibration

[VTMopar]

Looking for some thoughts/advice:     

We took my '70 Vert to Hemming's Car Show in Eastern Upstate NY yesterday -- almost 400 miles down & back.   Had a great ride -- and a great show -- lots of MOPARS -- and a beautiful day.   Had no problems (the Challenger was restored earlier this year) and it handles very well.  The 440 hums nicely -- although it tends to run towards the higher side of the temp range -- but not hot.   

However -- I noticed a sense of "vibration" a couple of times on the way down & back.  It was not a vibration through the steering wheel -- but sort coming from the whole car (I sensed it coming from under and or behind (we had the top down).    It happened twice over the 400 miles -- once on a bad stretch of road -- and once on a brand new road.    It's hard to describe -- it is not coming from the front (I can't feel it through the steering wheel) -- more like the whole car gets into a "rythem" where you "feel" it -- like a tire that is out of round or something.    It lasts a few miles -- then seems to dissapate.....   I also get the feeling that the engine is laboring a bit more.    It kind of reminds me of the sensation you get when you are on an old asphault road with periodic stress cracks every several feet -- you feel them -- (this is not what I was driving on -- just gave me that similar sensation).    The tires are new; lugs are tight (new studs all around); no visable issues.......  and 99% of the time, it rides smooth as glass......   

Because it is intermittent -- hard to figure out.   Any ideas?

Vermont MOPAR   

[71chmark]

Universal joint going bad is my guess.

[MEK-Dangerfield]

Is speed a factor here? What I mean is... did it only vibrate when you reached a certain speed, or was it at different speeds?


  Mike

[VTMopar]

Mike:  No, speed didn't seem to matter..... I slowed down a bit and no change.    Again, after a few miles it just kind of worked it way out of it......     

Is there a quick & easy way to check the U-Joint?   

Doug

[Chryco Psycho]

put the car in neutral , blocking the car & check to see if either joint is loose

[BIGSHCLUNK]

Check your upper ball joits. I had a wierd prob w my F150 . Truck drives/handles /stops nice, but every once in awhile for just a second or 2 felt like a contry road rumble strip. No vibration in the wheel /no wierd pattern in the tire tread. Worth a shot....   working:

[VTMopar]

Well, got the car up this afternoon and the U Joint is fine -- no play in it whatsoever.  I'm a bit disappointed -- would have been an "easy" fix......    I will take some time to check on those ball joints tomorrow.....

Vermont MOPAR

[Moparal]

Water inside one of the tires?
center section picking up old gasket material in the oil as you are running?
Pinion nut a little loose
Ubolt shakle nuts not tight
A shock going bad or the bolt is loosening up on top
Transmission mount bolt loose a bit
Brake adjuster wheel not adjusted and dragging the brakes causeing dust bumps


The road just happened to really suck in that certain spot at the time
Passenger motor mount loose
tortion bar creeping back in the hole ( hope the clips in)
Sway bar bushings not tight
Sway bar mount to frame loose
Exhaust bracket bad
Exhaust pipe touching on frame or tq rods

Im running out of ideas

[Bullitt-]

You said it & I am reminded of several experiences I have had with road noise, sometimes on older surfaces sometimes newer, where the harmonics would make you swear a tire was coming apart or something, then suddenly the sensation is gone......  I did have some rear drum brakes acting up once that would come & go giving a bad vibe occasionally...tap the brake & it would go away.

[JayBee]

I've had a couple vibration issues in the years:

1. Unbalanced driveshaft
2. Tailstock output shaft bearing

[VTMopar]

Yipes!    Now there's a menu of options to check out!       

Vermont MOPAR

[AARCuda340+6]

What JayBee said...   I had a bent driveshaft on my AAR so took it over to a shop and had it straitened & balanced.  This made a huge difference and got rid of most of my vibration.  I tried changing tires, rims and that never got rid of my vibration but when the driveshaft was repaired it smoothed out the ride.

[drewcrane]

check your rotors, drums,wheel bearings,hey i have had a bad pully on a power steering pump cause a vibration through the whole car

[Aussie Challenger]

  Definetly sounds like driveline problems, is the slip joint in far enough in the back of your gearbox/trans.
  Are the uni-joints seated properly in the diff flange or a circlip come out holding the joint in the tail shaft/slip joint.
  You may need to check to see a needle roller dropped down if you have just installed new uni-joints, they will be very hard to operate properly.     
  Has a balance weight come off of the shaft or is it bent. You may have to put some axle stands under the rear axle housing and run the car in gear and watch the shaft turn, if doing this have somebody else in the car for safety.
  Is the diff pinion angle correct. Likewise the angle of the gearbox.
   

[LAA66]

 There is a stretch of highway 101 in my area that causes my truck to do something similar. It's good AC paving and all but it happens everytime in that one section.