Drivetrain vibration

[Scooter]

Picked the wrong weekend to pull the Challenger apart... it's going to be near 70 and sunny today!! Have had a slight drivetrain vibration since I bought the car. It changes as I get on and off the throttle but is always there to some degree. Thought it might be u-joints so I dropped the driveshaft last night intending to replace them. Got the shaft on the bench and the u-joints actually seem fine. Move freely and no slop I can feel. Replacing them anyway as I already have the parts and tools on hand. Might have the driveline balanced just to be sure next week.

One thing I did notice was there seems to be a lot of "play" in the yoke before the rear wheels turn. Thinking maybe the ring & pinion might be out of adjustment or worn. Is there a rule of thumb for how many degrees you should be able to turn the yoke before the wheels engage?

[jordan]

I bought a pretty beat challenger in the mid 90s.  It had a horrible vibration.  Shake the whole car kind of vibration.  I took the drive shaft in for new u-joints and a balance.  The guys there said the shaft was bent and need straightening.   That's what put it out of balance.  Best $100 spent on a car.  I would take it in for a balance at least for piece of mind. 

[Chryco Psycho]

If there is no noise the Ring & Pinion are ok but the axle gears inside could be worn out .
Vibrations can be hard to trace , it could be anything , bad tires are common especially if they are BFGarbage , even when balanced they can be badly out of round .

[Scooter]

^^^ Well I got the u-joints done and just drove it prolly 80 miles. Vibration is near entirely gone.. better by 90% easy. The rest could be coming from other source. Odd tho.. the u-joints I pulled off did not look or feel bad. I do have an old set of BFG radials on it... they are probably next to go. 

[Racer57]

I had a vibration that took me 2 years to track down. The tranny output shaft bearing/bushing (forgot which it was) was shot.

[dodj]

My vibration a few years ago was pinion coming loose. Which led to the pinion gear walking back until it started to chew on the diff. Which led to a $1K rebuild...

The out of balance/round comment reminded me of an SUV I went by on the hwy a few days ago. He was going slow in the fast lane (like all the slow drivers around here) and as I went past him, the passenger side rear tire was visibly bouncing up and down a couple inches. We were going 110kmh. I figured a ride in that SUV must feel like you are in a paint shaker.
Also made me wonder what was more at fault...tire balance or shock or out of round?

[docmel]

I went thru the whole thing myself on my 71.   I would replace a thing  at a time  (Rims, shocks, tires, rubber bushings, balance drive shaf, u joints), and it would get a little bit better, but at about 60-70 MPH, I would still have a vibration.    Turned out the real culprit was the rear end.  Needed rebuilding.  Once that was done, smooth as glass.   

Remember, your rear dif is at least 50 years old, and no one likes to rebuild a rear end.  Its labor intensive and can be expensive

I went to a dif rebuilder in my area and we did a direct swap for my rear end for a complete rear axle and pumpkin, same gear ratio,  that he had rebuilt

That meant not only was the rear end rebuilt, so were all the axle related parts  (bearings, seals, etc), axle was repainted , for $1000 out the door.   

Check your yellow pages for rear end services


Ill bet money its in your rear end, or rear end related, period

[Scooter]

I'm starting to suspect some rear end vibration. I'm running the stock 2.76 open and it's never been touched as far as I can tell. The axle bearings and seals were replaced about 10 years ago.

[Scooter]

Just uploaded a quick video.... is this amount of play in the yoke typical?

[Chryco Psycho]

Billy Squire !
It doesn't look excessive , as i said the gears run quiet correct so the play is more likely in the spider & axle gears , do you have a sure grip & do you know what type if so ?

[Scooter]

Billy Squire !
It doesn't look excessive , as i said the gears run quiet correct so the play is more likely in the spider & axle gears , do you have a sure grip & do you know what type if so ?

Gotta do the stroke... 

2.76 open.. highway geared. if you think that's fine I'll look elsewhere.. maybe service it for good measure.

[Chryco Psycho]

If the gears run quiet & the pinion has zero movement in & out I believe the problem is elsewhere 
if it make noise while cornering that would be the spider & Axle gears talking to you .