Vibration @ 60mph - Chevelle Tech
Brakes, Suspension & Steering Conversion questions & more.

 15Likes
Reply
 
LinkBack Thread Tools Search this Thread Display Modes
post #1 of 25 (permalink) Old Dec 20th, 19, 2:09 PM Thread Starter
Tech Team
Tony
 
Join Date: Jan 2014
Location: Lucas, TX
Posts: 53
Vibration @ 60mph

Hey everyone,

I just finished a complete, ground-up rebuild on a '68 coupe. Here are the highlights:
  • 496 BBC
  • T-56 Magnum
  • Strange Dana S60
  • 3.5" steel driveshaft with 1350 joints
  • Tubular upper and lower rear control arms (uppers adjustable)

I'm getting a vibration around 55-60mph that seems to be occurring at driveshaft speed. I plan to take the driveshaft out and have the balance checked, but it's brand new (like everything else). I called the shop that made it, and they're willing to look at it but said it's likely to be something else.

I've had a similar issue in the past with a previous project and ended up just buying a carbon fiber driveshaft because I could never get it fixed. Knowing a bit about pinion angles as a result, I took out the driveshaft and confirmed the following:
  • The pinion yoke is parallel with the output shaft of the transmission
  • The pinion-to-driveshaft angle is about 1.7 degrees (nose down)
  • There is no slop in the joint sitting in the yoke. Both are new, so it's very tight.

It's possible that I'm underestimating the speed at which the tires are spinning at that speed and it's actually a wheel balance issue. I plan to check that, but I don't have high hopes. Any other things I should check or consider?
Gauge is offline  
Sponsored Links
Advertisement
 
post #2 of 25 (permalink) Old Dec 20th, 19, 5:16 PM
Senior Tech Team
Eric
 
Join Date: Aug 2011
Location: Poteau, Ok
Posts: 4,579
Re: Vibration @ 60mph

Tires and balance, wheels, and axle flanges.

Your just jealous because you can't hear the voices!

1967 Olds Cutlass 468 BBC/T400
1963 Plymouth Fury 440/Torqueflite
2007 Ford Mustang GT (momma's car)
oldcutlass is offline  
post #3 of 25 (permalink) Old Dec 20th, 19, 6:04 PM
Senior Tech Team
 
Join Date: Nov 2008
Location: Chevelle land USA
Posts: 1,868
Re: Vibration @ 60mph

Quote:
Originally Posted by Gauge View Post
Hey everyone,

I just finished a complete, ground-up rebuild on a '68 coupe. Here are the highlights:
  • 496 BBC
  • T-56 Magnum
  • Strange Dana S60
  • 3.5" steel driveshaft with 1350 joints
  • Tubular upper and lower rear control arms (uppers adjustable)

I'm getting a vibration around 55-60mph that seems to be occurring at driveshaft speed. I plan to take the driveshaft out and have the balance checked, but it's brand new (like everything else). I called the shop that made it, and they're willing to look at it but said it's likely to be something else.

I've had a similar issue in the past with a previous project and ended up just buying a carbon fiber driveshaft because I could never get it fixed. Knowing a bit about pinion angles as a result, I took out the driveshaft and confirmed the following:
  • The pinion yoke is parallel with the output shaft of the transmission
  • The pinion-to-driveshaft angle is about 1.7 degrees (nose down)
  • There is no slop in the joint sitting in the yoke. Both are new, so it's very tight.

It's possible that I'm underestimating the speed at which the tires are spinning at that speed and it's actually a wheel balance issue. I plan to check that, but I don't have high hopes. Any other things I should check or consider?
Correct me if Im wrong but shouldn't angle of DS at trans output be equal and opposite of angle of DS at the pinion? If its -1.7 at pinion shouldn't it be +1.7 at trans output
427L88 likes this.

Marc S


71 SS 454 ELCO
Edelbrock Proflo4
TKO600
Strange 12bolt w/4.10
1971ss454Elco is offline  
 
post #4 of 25 (permalink) Old Dec 21st, 19, 3:09 AM
Senior Tech Team
Chris
 
Join Date: Aug 2002
Location: Alberta, Canada
Posts: 6,097
Re: Vibration @ 60mph

I would double check the operating angles of your driveshaft. Tremec makes a nifty free app that is really easy to use.

You probably know this, but the angles should be checked with the vehicle at ride height and full weight on the suspension. It does not have to be perfectly level.

1971 Chevelle SS454, T56 Magnum 6 speed, 3.31 Posi

Youtube Channel.
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Instagram:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Twitter:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
-SS454- is online now  
post #5 of 25 (permalink) Old Dec 21st, 19, 11:16 AM
Tech Team
Jay
 
Join Date: Aug 2015
Location: Florida
Posts: 114
Re: Vibration @ 60mph

Quote:
Originally Posted by Gauge View Post
Hey everyone,

I just finished a complete, ground-up rebuild on a '68 coupe. Here are the highlights:
  • 496 BBC
  • T-56 Magnum
  • Strange Dana S60
  • 3.5" steel driveshaft with 1350 joints
  • Tubular upper and lower rear control arms (uppers adjustable)

I'm getting a vibration around 55-60mph that seems to be occurring at driveshaft speed. I plan to take the driveshaft out and have the balance checked, but it's brand new (like everything else). I called the shop that made it, and they're willing to look at it but said it's likely to be something else.

I've had a similar issue in the past with a previous project and ended up just buying a carbon fiber driveshaft because I could never get it fixed. Knowing a bit about pinion angles as a result, I took out the driveshaft and confirmed the following:
  • The pinion yoke is parallel with the output shaft of the transmission
  • The pinion-to-driveshaft angle is about 1.7 degrees (nose down)
  • There is no slop in the joint sitting in the yoke. Both are new, so it's very tight.

It's possible that I'm underestimating the speed at which the tires are spinning at that speed and it's actually a wheel balance issue. I plan to check that, but I don't have high hopes. Any other things I should check or consider?
I had a similar issue with my 1970 Chevelle SS when driving at speeds of 60 mph and above causing vibration. I checked the driveshaft for balance, trans, driveshaft & pinion angles which turned out to be all okay. I checked the rims and tires for balance and all were okay as well. However, while checking the rims and tires for balance I noticed some of the rims were out of round both lateral and radial. I pulled the tires off all 4 rims and all four rims were out of round. Turns out the 4 rims were reproduction rims purchased from the previous car owner. If you have reproduction rims on your 68 Chevelle I would check the rims to determine if the rims are running true and not out of alignment laterally and radially.
NickeyChevelle likes this.

Jay

1970 Chevelle SS L-34
jjr158 is offline  
post #6 of 25 (permalink) Old Dec 21st, 19, 11:38 AM
Lifetime Premium Member
 
Join Date: Oct 2005
Location: CT,USA
Posts: 12,844
Re: Vibration @ 60mph

Back in 2003-2006 I had a a pump gas, low 12 second daily driver. I had a [email protected] MPH that drove me crazy after replacing the factory driveshaft, installing a new $700 torque converter, and performing two ring and pinion gear swaps myself, (the reason for the gear swaps being that I went from 3:55, to 4.10, to 4.56 rear gear ratio) and after three tire/wheel balances, a guy told me about something called a "road force" tire/wheel balnce.

It wasn't cheap because not all places have the equipment to perform a road force tire balance. I found a local dealer which had the equipment, and back in 2006 they charged me $320 to do it on all four wheels, but it took away the vibration for good. Problem was solved. So for me it was worth every penny of the $320 I spent. The road force balance machine has a computer with an electronic key pad which requires the operator/mechanic to type in the make and model of vehicle, and I believe also the VIN, and the tire wheel combo gets mounted onto a hydraulic arm of the road force balance machine, which uses hydraulics in the arm to press the tire up against a rolling pad while it's being balanced to simulate the actual vehicle weight that is on the tire while it's on your car as you're driving. It's a more accurate way of tire balancing.

I found a list of the nearest places that had road force balancing machines by going onto the Hunter road force balancing equipment website, and punching in my zipcode. I believe that Hunter is just one of the brands that are used. I hope this helps you.
Kirk's67SS likes this.

70 Chevelle SS clone (632 CI powered).
BillyGman is offline  
post #7 of 25 (permalink) Old Dec 21st, 19, 1:27 PM
Senior Tech Team
Eric
 
Join Date: Aug 2011
Location: Poteau, Ok
Posts: 4,579
Re: Vibration @ 60mph

Any Discount tire can do a road force balance.

Your just jealous because you can't hear the voices!

1967 Olds Cutlass 468 BBC/T400
1963 Plymouth Fury 440/Torqueflite
2007 Ford Mustang GT (momma's car)
oldcutlass is offline  
post #8 of 25 (permalink) Old Dec 23rd, 19, 10:40 AM Thread Starter
Tech Team
Tony
 
Join Date: Jan 2014
Location: Lucas, TX
Posts: 53
Re: Vibration @ 60mph

Thanks for all the replies. I've been dealing with some other issues, so I haven't done much to tackle this yet. I did the math, and at 55mph my wheels should be spinning ~11 revolutions per second. I could be convinced that my vibration is at 11Hz, so it's definitely possible that it's the wheels. I remember the guy at the shop who mounted my tires saying that the wheels were not balanced well and that it was hard to balance them after putting on the tires, so that's a likely culprit.

I put the car on jack stands and put it in put it in gear and got out to look. The tread tracked straight and everything looked somewhat alright. We'll see what they say when I try to get it balanced again. I'll keep this thread updated for posterity's sake.
davewho1 likes this.
Gauge is offline  
post #9 of 25 (permalink) Old Dec 23rd, 19, 2:10 PM
Gold Member
Gene
 
Join Date: Sep 2000
Location: Buffalo NY
Posts: 14,769
Re: Vibration @ 60mph

my oem SS rims where this way. The issue only went away with a new set of Torque Thrusts.

Gene
ACES 3112/Team Chevelle Gold #62
Be big, be a 'builder'!
427L88 is offline  
post #10 of 25 (permalink) Old Dec 23rd, 19, 2:56 PM
Super Mod
Mr Bill
 
Join Date: Aug 1998
Location: Waldorf Md. USA
Posts: 12,108
Re: Vibration @ 60mph

Anthony,
Depending on what Smartphone you have there are a couple of vibration sensing apps available. Not sure how accurate they are. I imagine it depends on the accuracy of your phones sensor.

Also, a lot of better auto repair shops will have one. Maybe you could find someone that will do a check for you ?

Just a thought,

Bill Koustenis
Advanced Automotive Machine
Waldorf Md


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


1971 Heavy Chevy - original owner
1984 Buick Riviera - original owner (Wife's car)
Team Chevelle #100
BillK is online now  
post #11 of 25 (permalink) Old Dec 23rd, 19, 3:12 PM
Senior Tech Team
Jeff
 
Join Date: Jun 2009
Location: Pittsburgh, Pa.
Posts: 2,414
Re: Vibration @ 60mph

I only use the road force balancer. That's easy, the issue comes from finding a tech who knows how to run it.. I have one about 20 miles from me on rt 228 called Fleming Tire service. They are top notch..

Any time I ever had vibration issues, after replacing a bunch of parts it always ended up being the tires...
hydro462 is offline  
post #12 of 25 (permalink) Old Dec 24th, 19, 12:14 AM
Tech Team
Dennis
 
Join Date: Sep 2000
Location: Walnut Creek, CA
Posts: 754
Garage
Re: Vibration @ 60mph

If your tire guy says he has a tire thatís difficult to balance or if you have a wheel/tire with a ton of weights, ask them to break the bead and rotate the tire 90 or 180 degrees on the rim and try it again. Sometime a heavy spot on a rim an a heavy spot on a tire get lined up and it takes a ton of weights to offset.
BillyGman likes this.

66 Chevelle hardtop - LFX 3.6 liter V6/6L50 6 speed auto trans, 3.07 10 bolt, full Hotchkis suspension, Wilwood 4 wheel discs, white with red interior, cowl hood.
67_LS1 is offline  
post #13 of 25 (permalink) Old Jan 20th, 20, 8:12 PM Thread Starter
Tech Team
Tony
 
Join Date: Jan 2014
Location: Lucas, TX
Posts: 53
Re: Vibration @ 60mph

I haven't messed with this much, but today I took the wheels/tires somewhere else to balance. They complained about the one tire a bit but said they were able to get it zeroed out. They used less than 2oz of weight to do it.

When I got home, I jacked the car up by the differential and put it in 5th and got it up to 60mph. I could feel the vibration. I took off the supposedly problematic wheel and tried again. I could still feel it. I took off the other wheel, and no change. So, this is not a wheel/tire problem.

I called the guy who built the driveshaft asking if I could take it to him and have him check it, and he agreed. However, he insisted I was barking up the wrong tree because if it was out, he'd have seen it when he built it. I see the logic. I'm going to bring it to him, but likely in vain.

All this leaves, in my mind, is driveshaft angles (which I've been very diligent about from the start as I've had these problems before) or something with the rear end (which is brand new) or possibly even the rear brakes. I got no other ideas. I'm so frustrated I'm just sick to my stomach about it.

1968 Chevelle 2-door coupe restomod... 496ci BBC, Holley 950, T-56 Magnum, Dana S60, and an idle that shakes the ground.
Gauge is offline  
post #14 of 25 (permalink) Old Jan 20th, 20, 9:07 PM
Senior Tech Team
Steve
 
Join Date: Sep 2015
Location: Central MA
Posts: 1,417
Re: Vibration @ 60mph

What kind of rear brakes do you have on it?

Iíve seen bad drums cause problems like this before, either out of round or out of balance. And Iíve seen brand new drums that were out of round and/or out of balance, so even if they are new, they could be a problem.

1972 Chevelle, 454, 200-4r non-lockup, 12 bolt 3.73
1981 Camaro Z28, 355, TH350, 3.73
lucifershammer is offline  
post #15 of 25 (permalink) Old Jan 20th, 20, 9:33 PM
Tech Team
Stan
 
Join Date: Jan 2004
Location: Alberta, Canada
Posts: 501
Re: Vibration @ 60mph

Have you tried quickly stabbing in the clutch when vibration at its worse?
stanski is offline  
Sponsored Links
Advertisement
 
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Chevelle Tech forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
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. Note, you will be sent a confirmation request to this address.

Email Address:
OR

Log-in










Thread Tools Search this Thread
Show Printable Version Show Printable Version
Email this Page Email this Page
Search this Thread:

Advanced Search
Display Modes
Linear Mode Linear Mode



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

 
For the best viewing experience please update your browser to Google Chrome