1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

mysterious 35mph death wobble

Thread Tools
 
Search this Thread
 
Old 10-12-06, 05:05 PM
  #1  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
mysterious 35mph death wobble

as th4e title says my car has a death wobble at 35mph. Car shakes pretty hard in all gears at 35mph, even nutral. slower then 35 and faster then 35 I can still feel it although it is liveable.

Where to start looking ?
Old 10-12-06, 05:18 PM
  #2  
Senior Member

 
speedracer_not's Avatar
 
Join Date: Dec 2004
Location: alabamer
Posts: 502
Likes: 0
Received 1 Like on 1 Post
front wheels, lift them off the ground, and shake them with your steering wheel ignition locked.

hands on each side to tire, try to move back and forth, if it moves you have a pitman arm bushing, or tie rod end problem, there will be about 1/4 inch movement which translates to steering wheel.

hands on top and bottom, try to move back and forth, if it moves you have a wheel bearing problem.

Also your wheel lug nuts might be loose. but they would have come loose by now, wheel would have fallen off, and you'd be dead.
Old 10-12-06, 05:20 PM
  #3  
JDGJr

 
JDGJr85GSLSE's Avatar
 
Join Date: Aug 2004
Location: 7400 ft plus jack stands
Posts: 141
Likes: 0
Received 0 Likes on 0 Posts
less likely, but possible - check that you have all the bolts @ the rear of the drive shaft. Or possibly your shaft is bent.
Old 10-12-06, 05:55 PM
  #4  
Lives on the Forum

 
Kentetsu's Avatar
 
Join Date: Jun 2004
Location: Grand Rapids Michigan
Posts: 11,359
Received 14 Likes on 11 Posts
Bad tire?
Old 10-12-06, 07:16 PM
  #5  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by speedracer_not
front wheels, lift them off the ground, and shake them with your steering wheel ignition locked.

hands on each side to tire, try to move back and forth, if it moves you have a pitman arm bushing, or tie rod end problem, there will be about 1/4 inch movement which translates to steering wheel.

hands on top and bottom, try to move back and forth, if it moves you have a wheel bearing problem.

Also your wheel lug nuts might be loose. but they would have come loose by now, wheel would have fallen off, and you'd be dead.
new tie rods about three weeks ago and they are good still
new wheel barrings about two weeks ago and they are good still
rotated the tires a few mins ago
Old 10-12-06, 07:17 PM
  #6  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by JDGJr85GSLSE
less likely, but possible - check that you have all the bolts @ the rear of the drive shaft. Or possibly your shaft is bent.
checked the driveshaft and its cool
Old 10-12-06, 07:18 PM
  #7  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by Kentetsu
Bad tire?
nah checked the tires when I rotated them a few mins ago
Old 10-12-06, 07:27 PM
  #8  
GSSL-SE

iTrader: (1)
 
1badFB's Avatar
 
Join Date: Aug 2003
Location: Canada
Posts: 1,332
Received 165 Likes on 86 Posts
If it only happens at a certain speed, not reliant on the engine RPM, It is most likely something to do with your driveshaft, rear end, or wheels. It could have to do with the rear part of your transmission but thats unlikely... It seems like you did some repairs not too long ago...when did the problem begin?
There are lots of possibilities for problems even though everything "looks fine" so pinpointing what was worked on and when the problem started is key.
Old 10-12-06, 07:30 PM
  #9  
GSSL-SE

iTrader: (1)
 
1badFB's Avatar
 
Join Date: Aug 2003
Location: Canada
Posts: 1,332
Received 165 Likes on 86 Posts
Also, if you dont feel it any more in the steering wheel than the whole car overall, chances are its somewhere from the transmission back.. And if you do feel it in the steering wheel, then its most likely a problem in the front suspension/wheels.
Old 10-12-06, 07:56 PM
  #10  
Leave A Message

 
GavinJuice's Avatar
 
Join Date: Sep 2003
Location: MN
Posts: 1,454
Likes: 0
Received 1 Like on 1 Post
Originally Posted by notveryhappyjack
even nutral.
drive speed shouldn't be a factor then, or the driveshaft or axle wheel etc.
Old 10-12-06, 08:04 PM
  #11  
GSSL-SE

iTrader: (1)
 
1badFB's Avatar
 
Join Date: Aug 2003
Location: Canada
Posts: 1,332
Received 165 Likes on 86 Posts
Originally Posted by GavinJuice
drive speed shouldn't be a factor then, or the driveshaft or axle wheel etc.
I assumed he just meant coasting at 35 mph in neutral...unless the car shakes in neutral when the car is stopped its irrelevant.
Old 10-12-06, 08:46 PM
  #12  
Thunder from downunder

iTrader: (1)
 
aussiesmg's Avatar
 
Join Date: Mar 2001
Location: Convoy, Ohio, USA
Posts: 3,843
Likes: 0
Received 1 Like on 1 Post
Sounds like wheel balance problem to me. Check all lugs are correctly secured also.
Old 10-12-06, 08:48 PM
  #13  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
i don't think that the problem is tranny/engine/clutch related for the fact that the shaking happends in 2nd at 35, 3rd at 35, 4th at 35 and even in neutral at 35.

I just went for a test drive after rotating the tires and checking the steering/undercarige and it seemed to shake less, I'm not really sure. I have a feeling that one of the wheel balance weights might have fallen off on my 150 mile road trip I made last weekend.

I will be getting an allignment (needed anyways) and I will have them re-balance the tires (last time they were balanced was about three years ago by previous owner) and see if that helps out.
Old 10-12-06, 08:49 PM
  #14  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Is there a weight balance on the drive-shaft that could have come loose ?

What about engine mounts/ transmission mounts <--could they be the cause of the shaking ?
Old 10-12-06, 08:50 PM
  #15  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by aussiesmg
Sounds like wheel balance problem to me. Check all lugs are correctly secured also.
yeah thats what I'm hopeng lol
Old 10-12-06, 08:50 PM
  #16  
Senior Member

 
speedracer_not's Avatar
 
Join Date: Dec 2004
Location: alabamer
Posts: 502
Likes: 0
Received 1 Like on 1 Post
as my drive shaft u joints went out, there was an intermittant banging noise. It didn't shake the car, it made a lot of noise. I'd put the clutch in, coast, and then it would stop, release the clutch, and it would not return.

Your mentioning the specific speed points to the drive shaft, differrential, or rear/front wheel assembly.

Interesting problem though, let us know how it turns out.
Old 10-12-06, 08:50 PM
  #17  
Josh

 
Rotererer's Avatar
 
Join Date: Mar 2005
Location: New Zealand
Posts: 55
Likes: 0
Received 0 Likes on 0 Posts
When you rotated the tyres one of the balance weights might have been knocked off. That happened to me and i got the vibration at a slower speed. It can cause a pretty bad wobble when they're out of balance. Its pretty cheap to get them balanced and its a good place to start before changing driveshafts around
Old 10-12-06, 08:51 PM
  #18  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by Gen1onr
I assumed he just meant coasting at 35 mph in neutral...unless the car shakes in neutral when the car is stopped its irrelevant.
yes coasting, nothing ab-normal happends while stopped in neutral
Old 10-12-06, 08:54 PM
  #19  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
another question, the car is a 85GS, the driveshaft/rear unit is a 82 GSL. I forget from my swap if the u-joints can be replaced on the 82 or on the 85.

Which year is it because one of the years cannot be replace and one can ?
thanks for all the help everyone
Old 10-13-06, 08:38 AM
  #20  
Waffles - hmmm good

iTrader: (1)
 
t_g_farrell's Avatar
 
Join Date: Jul 2004
Location: Lake Wylie, N.C.
Posts: 8,783
Received 282 Likes on 232 Posts
83 and up have non servicable ujoints according to Mazdatrix site. I've heard of folks replacing the ujoints on these drive shafts but I think they had a tranny shop do them. You may be lucky if its really an 82, because then they are like 20 bucks for each ujoint and pretty easy to replace. Didn't you do this when the new rear end went in ? Tsk tsk.

BTW, my best guesses are engine/tranny mounts, ujoints, or bent rear axle. If it was a wheel balance issue it would follow the wheel around and you'd be able to feel which corner was wobbling.
Old 10-13-06, 09:36 AM
  #21  
Rotor Power Rules

iTrader: (5)
 
Bruceman's Avatar
 
Join Date: Jul 2001
Location: Rochester Hills, MI
Posts: 525
Received 2 Likes on 1 Post
1) Remove driveshaft
2) Get it balenced
3) Reinstall driveshaft

If you don't do this you are just pissing into the wind
Old 10-13-06, 11:31 AM
  #22  
unregistered rex offender

 
bstrange99's Avatar
 
Join Date: Oct 2003
Location: Spokane, Washington
Posts: 1,644
Likes: 0
Received 0 Likes on 0 Posts
I'd start by checking the idler arm bushings. They're easy to check, and chances are they need replaced anyway. It's definately a good investment at $30 bucks, and 10 minutes.
Old 10-13-06, 05:26 PM
  #23  
Lives on the Forum

 
Kentetsu's Avatar
 
Join Date: Jun 2004
Location: Grand Rapids Michigan
Posts: 11,359
Received 14 Likes on 11 Posts
In my opinion, the fact that it changed when you rotated the tires pretty much narrows it down to a tire/wheel issue...
Old 10-13-06, 05:35 PM
  #24  
Retired Moderator, RIP

iTrader: (142)
 
misterstyx69's Avatar
 
Join Date: Sep 2005
Location: Smiths Falls.(near Ottawa!.Mapquest IT!)
Posts: 25,581
Likes: 0
Received 131 Likes on 114 Posts
+1 with Kentetsu..I'd try Checking/Rotating Tires Again (It's FREE)..checking Wheel nuts.you could have just Put on a Wheel a little ****-eyed.(you know,when you tighten up the wheel nuts and they all "seem Tight" but the Wheel is still not Flush on )..
Old 10-13-06, 06:42 PM
  #25  
1 bar boost

Thread Starter
iTrader: (4)
 
notveryhappyjack's Avatar
 
Join Date: Jun 2005
Location: Seattle, Washington
Posts: 2,753
Received 5 Likes on 3 Posts
Originally Posted by t_g_farrell
83 and up have non servicable ujoints according to Mazdatrix site. I've heard of folks replacing the ujoints on these drive shafts but I think they had a tranny shop do them. You may be lucky if its really an 82, because then they are like 20 bucks for each ujoint and pretty easy to replace. Didn't you do this when the new rear end went in ? Tsk tsk.

BTW, my best guesses are engine/tranny mounts, ujoints, or bent rear axle. If it was a wheel balance issue it would follow the wheel around and you'd be able to feel which corner was wobbling.
yeah its a for sure 82 gsl rear end, I remember now that the 82's had replacible u-joints. No I did not replace the u-joints, lol that prolly would have been the correct way to do it but I just pulled the driveshaft off a junk yard car and put it in to mine.
Wheel barrings are pretty new -within the last year I had then both serviced in the last month cause they were becoming loose.


Quick Reply: mysterious 35mph death wobble



All times are GMT -5. The time now is 07:14 PM.