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Techical Discussions => Tech- - DRIVE TRAIN => Topic started by: Dan Cluley on April 08, 2009, 11:46:15 PM

Title: Noise/vibration from rear
Post by: Dan Cluley on April 08, 2009, 11:46:15 PM
The Dart has a little bit of a pulsing noise/vibration that I think is coming from somewhere in back.
 
My first thought was tire a little out of balance, but swapping things around with a couple of different tires and wheels doesn't seem to make a difference.
 
It's subtle enough that I 'm not 100% sure whether turns make a difference.
 
Coasting in neutral with engine off does not seem to make it better or worse.
 
It does seem to mostly go away when in reverse.
 
Any thoughts?
Title: Noise/vibration from rear
Post by: Leaburn Patey on April 09, 2009, 01:39:06 AM
Drop the drive shaft and check the u joints.Any binding of them can cause a noise/vibration.  
Title: Noise/vibration from rear
Post by: Snotty on April 09, 2009, 10:05:21 AM
I agree with the above.
 
Also, does the vibration change when you turn right or left?  You could have a rear bearing starting to go out.
Title: Noise/vibration from rear
Post by: Dan Cluley on April 09, 2009, 05:11:12 PM
U-joints are next on the list to look at. 

 
I thought maybe the goes away in reverse would mean something obvious.
 
I don't think it changes when turing either way, but as I said this is still a pretty subtle noise, so I'm not 100% sure
Title: Noise/vibration from rear
Post by: Robert Rottman on April 10, 2009, 04:44:20 AM
Dan, I just had my rear end rebuilt in my 70 Fury this week. I knew I had recently replaced u-joints (by previous owner) so I knew that wasn't the problem. Reason for the work? I had low speed growling back there...didn't seem to change when making turns...It turned out to be the pinion bearing...Expensive fix...so yes, make sure your u-joints are ok first..Steve told me too...If the noise doesn't change when you make left/right turns it could then be the pinion. My Fury has 95,000 miles on it...The good news...After $700.00 rebuild of the rear end...the car sounds like new now...
 
Bob
Title: Noise/vibration from rear
Post by: Dan Cluley on April 10, 2009, 04:57:31 PM
I'm pretty sure there's a problem with the u-joint.
 
I unbolted the clamps that hold the u-joint to the pinion yoke.  Those two bushings rotate easily on the cross piece, however I could not move the cross relative to the driveshaft yoke.
 
Those bushings should be free to swivel as well, correct?
Title: Noise/vibration from rear
Post by: Steve on April 10, 2009, 05:09:17 PM
Simple way to tell is to see if there is any rust around the cups on th einside of the joint.
Title: Noise/vibration from rear
Post by: Snotty on April 13, 2009, 09:38:21 AM
Quote from: furyfever
...After $700.00 rebuild of the rear end...the car sounds like new now...
 
 
That's a darn-good price Bob.  It's a lot cheaper than buying a new rear, or even a used one.  Good for you!
Title: Noise/vibration from rear
Post by: Robert Rottman on April 21, 2009, 10:42:00 AM
Quote from: Snotty
Quote from: furyfever
...After $700.00 rebuild of the rear end...the car sounds like new now...
 
 
 
Well Thanks Snotty...That makes feel a little better. I thought it was a bit much...especailly after a guy here at work said it should have been about 1/2 that. The mechanic that did the work explained to me what was involved...I knew it was beyond my capabilities. It was getting loud enough back there that I didn't want to take the car very far from home anymore...especially after I read a post over on C-Body Dry Dock...where a guy lost a rear axle on his 69 Monaco and it destroyed the car....He blamed it on a green wheel bearing...After I read that, I called and made an appointment...
 
Bob
 
furyfever2009-04-21 15:43:49
Title: Noise/vibration from rear
Post by: Steve on April 21, 2009, 05:46:39 PM
Gee. . .I got something right for a change.  I'll let thet crystal ball live another day I guess.

Title: Noise/vibration from rear
Post by: Dan Cluley on April 22, 2009, 01:40:01 AM
No, not yet.   Snow, rain, and a week with the flu have put a hold to projects this month.
 
 
Title: Noise/vibration from rear
Post by: Arlen Vander Hoff on April 22, 2009, 03:17:17 PM
Quote from: D Cluley
I'm pretty sure there's a problem with the u-joint.
 
I unbolted the clamps that hold the u-joint to the pinion yoke.  Those two bushings rotate easily on the cross piece, however I could not move the cross relative to the driveshaft yoke.
 
Yes Dan they both should move easily.