Car shakes in rear? - Page 2 - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Transmission - Rearend
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #16 (permalink)  
Old 01-27-2013, 05:40 PM
Registered User
 
Join Date: Aug 2012
Posts: 50
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Thanks, I had the driveshaft checked, it was out, so they balanced it, I also re-adjusted the pinion angle for -2, the trans mount is good also, none of this changed the way the car reacts from before, I also installed non-adjustable upper arms from UMI, I then installed lower "adjustables" to currect the pinion agle & side too side tracking, still does the same thing, It really feels like a slightly bent driveshaft to me, but they showed me it on the machine as it was spinning with the dial indicator, The rear joint should be fine as it is new, its a combination joint, its sitting in the saddle good & snug from the looks of it.

I do know that the 9" sites off to one side on the pinion then the factory rear, could this cause a problem at a side angle? It still looks like the driveshaft is going fairly straight back in the tunnel.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #17 (permalink)  
Old 01-27-2013, 06:21 PM
Registered User
 
Last photo:
Join Date: Jul 2011
Location: Wentzville,MO
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
I fought a buzzing vibration like that on a Chevelle with narrowed 9". Turned out the big tires and wheels needed load balanced on a Hunter machine.
Reply With Quote Quick reply to this message
  #18 (permalink)  
Old 01-27-2013, 06:51 PM
Registered User
 
Join Date: Aug 2012
Posts: 50
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by Blown496 View Post
I fought a buzzing vibration like that on a Chevelle with narrowed 9". Turned out the big tires and wheels needed load balanced on a Hunter machine.
I run 2 sets of tires/rims with the same problem, so i'm thinking i need to rule that out. But who knows. Is this type of balancing done on like dyno machines??

275/60/15 Coopers & 26x11.5 MT ET Street bias ply.
Reply With Quote Quick reply to this message
  #19 (permalink)  
Old 01-27-2013, 08:01 PM
prostreet6t9's Avatar
Differential/Driveline
 
Last photo:
Join Date: Sep 2008
Location: oregon
Age: 51
Posts: 1,718
Wiki Edits: 0

Thanks: 5
Thanked 40 Times in 37 Posts
Quote:
Originally Posted by LJM97Z View Post
Thanks, I had the driveshaft checked, it was out, so they balanced it, I also re-adjusted the pinion angle for -2, the trans mount is good also, none of this changed the way the car reacts from before, I also installed non-adjustable upper arms from UMI, I then installed lower "adjustables" to currect the pinion agle & side too side tracking, still does the same thing, It really feels like a slightly bent driveshaft to me, but they showed me it on the machine as it was spinning with the dial indicator, The rear joint should be fine as it is new, its a combination joint, its sitting in the saddle good & snug from the looks of it.

I do know that the 9" sites off to one side on the pinion then the factory rear, could this cause a problem at a side angle? It still looks like the driveshaft is going fairly straight back in the tunnel.
Where on the driveline did they show you it was straight? On the ends? or? Do they have a balancer to fine tune it?
Reply With Quote Quick reply to this message
  #20 (permalink)  
Old 01-27-2013, 09:43 PM
Registered User
 
Last wiki edit: General Motors transmissions Last photo:
Join Date: Mar 2006
Location: near Yellowstone park
Posts: 4,209
Wiki Edits: 27

Thanks: 11
Thanked 233 Times in 219 Posts
side angle

Spicer, U joints have a web site that has charts on how to compute the actual working angle, using the horizontal and verticle off sets. up and down and side to side. Normally the trans output-crank shaft is down and the pinion angle should be UP, both angles paralled at load position. If your suspension components have a large difference in length the pinion angle will change a corresponding larger arc swing. The 2003 Ford GT, modern version of the old GT40, has the rear half shafts running at an angle. It looks strange when I was used to looking at a Jag or Corvette rear suspension. We had links a few months ago when someone else was having drive shaft problems
Reply With Quote Quick reply to this message
  #21 (permalink)  
Old 01-27-2013, 09:57 PM
Registered User
 
Last wiki edit: General Motors transmissions Last photo:
Join Date: Mar 2006
Location: near Yellowstone park
Posts: 4,209
Wiki Edits: 27

Thanks: 11
Thanked 233 Times in 219 Posts
spicer info

I searched spicer drive line installation guide. http://www2.dana.com/pdf/J3311-1-DSSP.pdf The trig to calculate working angles is a couple pages and complicated. the above link is 19 pages n good info .
Reply With Quote Quick reply to this message
  #22 (permalink)  
Old 01-28-2013, 05:20 AM
Registered User
 
Last photo:
Join Date: Jul 2011
Location: Wentzville,MO
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Quote:
Originally Posted by LJM97Z View Post
I run 2 sets of tires/rims with the same problem, so i'm thinking i need to rule that out. But who knows. Is this type of balancing done on like dyno machines??

275/60/15 Coopers & 26x11.5 MT ET Street bias ply.
I could not get it to vibrate off the ground. Finally stumbles into a tire store that does a lot of big drag tire stuff and he tole me I needed an experienced operator to force balance them. Here is a link for locating the nearest shop.
Hunter GSP9700 Wheel vibration Control System solves wheel vibration and tire pull problems that balancers and aligners can't fix
Reply With Quote Quick reply to this message
  #23 (permalink)  
Old 01-28-2013, 06:59 PM
Registered User
 
Join Date: Aug 2012
Posts: 50
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by Blown496 View Post
I could not get it to vibrate off the ground. Finally stumbles into a tire store that does a lot of big drag tire stuff and he tole me I needed an experienced operator to force balance them. Here is a link for locating the nearest shop.
Hunter GSP9700 Wheel vibration Control System solves wheel vibration and tire pull problems that balancers and aligners can't fix
I too put mine on stands, the drivetrain was very smooth, Now i do have one of the rims taking over 9 onces of weight, could this cause a problem even though it balanced out?

What exactly is force balance?
Reply With Quote Quick reply to this message
  #24 (permalink)  
Old 01-28-2013, 07:19 PM
Registered User
 
Last wiki edit: General Motors transmissions Last photo:
Join Date: Mar 2006
Location: near Yellowstone park
Posts: 4,209
Wiki Edits: 27

Thanks: 11
Thanked 233 Times in 219 Posts
dynamic balance

I have an old BEAR brand Balancer. It does both static balance and dynamic balance. static balance is like balancing a bicycle tire. It is free to turn by it's self and the heavy spot goes to the bottom. You wrap some wire around spokes on the light side until it doesn't turn. from any position on the clock That is how I balance the wire wheels on my 22 T antique racer. Dynamid balance is spin balancing. If you tie a lug nut on a 16 in piece of string and and slowly start spinning it horizontal, the string will NOT be horizontal at slow speeds. when you get it up to speed it will spin with the string horizontal. When the heavy spot on a tire is not centered but on either the inside or outside of the tire, at speed it will try to move that spot towards the center line giving you a wobble force. I don't remember what the factory spec was on wheel weights but I try to keep them under 6 oz. More than that and the tire will go on one of the farm trailers. or equipment for field use
Reply With Quote Quick reply to this message
  #25 (permalink)  
Old 01-29-2013, 10:05 AM
Registered User
 
Last photo:
Join Date: Jul 2011
Location: Wentzville,MO
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Look up that Hunter equipment or use the locator page and call one of them. They are very popular in the tire world. The machine uses a roller to simulate the tire on the ground under load. One of my tires had to be rotated to balance the heavy spots. I replaced the tires, yoke, all the bearings, new housing, new drums, new drive shaft and jacked the pinion angle up and down 1/2 degree at a time from 3 up to 3 down and the vib was always the same. I did runouts on wheels and axles and drive shaft and all was okay. I spent a lot of time and money before this $24 fix. I would guess that one of the Weld wheels is heavy on one side and the 29x18 wide Mickey radials don't help.
Reply With Quote Quick reply to this message
  #26 (permalink)  
Old 01-29-2013, 07:01 PM
prostreet6t9's Avatar
Differential/Driveline
 
Last photo:
Join Date: Sep 2008
Location: oregon
Age: 51
Posts: 1,718
Wiki Edits: 0

Thanks: 5
Thanked 40 Times in 37 Posts
Quote:
Originally Posted by LJM97Z View Post
Thanks, I had the driveshaft checked, it was out, so they balanced it, I also re-adjusted the pinion angle for -2, the trans mount is good also, none of this changed the way the car reacts from before, I also installed non-adjustable upper arms from UMI, I then installed lower "adjustables" to currect the pinion agle & side too side tracking, still does the same thing, It really feels like a slightly bent driveshaft to me, but they showed me it on the machine as it was spinning with the dial indicator, The rear joint should be fine as it is new, its a combination joint, its sitting in the saddle good & snug from the looks of it.

I do know that the 9" sites off to one side on the pinion then the factory rear, could this cause a problem at a side angle? It still looks like the driveshaft is going fairly straight back in the tunnel.
Was the shaft straight all the way down the shaft? Did they Balance the shaft on a machine?
Reply With Quote Quick reply to this message
  #27 (permalink)  
Old 01-29-2013, 07:52 PM
Registered User
 
Join Date: Aug 2012
Posts: 50
Wiki Edits: 0

Thanks: 0
Thanked 1 Time in 1 Post
Quote:
Originally Posted by prostreet6t9 View Post
Was the shaft straight all the way down the shaft? Did they Balance the shaft on a machine?
Yes it was balanced on a machine.
Reply With Quote Quick reply to this message
  #28 (permalink)  
Old 01-30-2013, 04:07 AM
Registered User
 
Last photo:
Join Date: Jul 2011
Location: Wentzville,MO
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
Have you talked to Brydon Papenburg? I assume that is who you bought the 9" from. GM is usually 1/2" offset. He can tell you how he built it.
Reply With Quote Quick reply to this message
  #29 (permalink)  
Old 01-30-2013, 04:10 AM
Registered User
 
Last photo:
Join Date: Jul 2011
Location: Wentzville,MO
Posts: 183
Wiki Edits: 0

Thanks: 0
Thanked 2 Times in 2 Posts
I will also add that the pinion angle should be opposite the engine angle. If engine is 3 degrees down pinion should be 3 degrees up. Parallel and opposite is the key.
Reply With Quote Quick reply to this message
  #30 (permalink)  
Old 01-30-2013, 09:44 AM
prostreet6t9's Avatar
Differential/Driveline
 
Last photo:
Join Date: Sep 2008
Location: oregon
Age: 51
Posts: 1,718
Wiki Edits: 0

Thanks: 5
Thanked 40 Times in 37 Posts
Quote:
Originally Posted by LJM97Z View Post
Yes it was balanced on a machine.
And the tube was straight all the day down the tube?
Reply With Quote Quick reply to this message

Recent Transmission - Rearend posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Whole car shakes? HotRodMan Engine 6 02-26-2008 07:19 AM
car shakes at idle and is fine during acceleration.. 84Z Engine 2 11-17-2007 07:33 PM
Got the shakes m-hauler Suspension - Brakes - Steering 5 09-17-2004 10:13 PM
car shakes when i shut it off! please help calimstng66 Engine 12 05-16-2004 11:30 PM
car shakes at 70mph fordracing Engine 6 04-03-2003 10:29 PM


All times are GMT -6. The time now is 10:17 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.