The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-31-2009, 01:36 PM   #1
GOPAPA
Registered User
 
GOPAPA's Avatar
 
Join Date: Oct 2007
Location: Nampa Idaho
Posts: 7,553
Truck Vibrates And Shimmy's At 50 MPH

My sons truck

This is a before and after picture of his truck.. He drove it after we put the all colored front clip on for 6 months or so and no problems .
Now it has problems with vibrating at 50 MPH ,,pretty bad.

The wheels on it now are what he drove on it before the wreck and after .

He had the front tires balanced ..he says the wheel berrings are pretty tight ,,hardly no movement by shoving in on top of wheel and pulling out on bottom ,,while jacked up..

It has sit out side through all weathers for close to a year ..

So,, why all of a sudden after driving with no problems ,,it now has this terrible vibrating a only 50 MPH ? papa



GOPAPA is offline   Reply With Quote
Old 03-31-2009, 01:56 PM   #2
Stock72c10
classic=of recognized value
 
Stock72c10's Avatar
 
Join Date: Sep 2008
Location: Wichita, KS
Posts: 317
Re: Truck Vibrates And Shimmy's At 50 MPH

Carrier bearing going out?
Stock72c10 is offline   Reply With Quote
Old 03-31-2009, 02:06 PM   #3
El Jay
Gone to greener pastures
 
Join Date: May 2007
Location: Gateway to the Delta
Posts: 7,354
Re: Truck Vibrates And Shimmy's At 50 MPH

^ x 2 ^, PL
__________________
'69 Chevy 1/2 T LWB Stepper: Daily Beater
'72 GMC 3/4 T Fleet: Another Daily Beater
'72 Plymouth Gran Coupe: ?


"Ah women. They make the highs higher and the lows more frequent." Friedrich Nietzsche

"Never kick a fresh turd on a hot day." Harry S. Truman

GUN CONTROL: Never having to say, "I missed you."

Always fire two warning shots into your attacker's chest area before putting a bullet between his eyes. Paraphrased from Louis Awerbuck

Last edited by El Jay; 03-31-2009 at 02:06 PM.
El Jay is offline   Reply With Quote
Old 03-31-2009, 02:14 PM   #4
Andy4639
Old member
 
Andy4639's Avatar
 
Join Date: Jan 2002
Location: Liberty, & Garden City S.C. , U.S.
Posts: 19,945
Re: Truck Vibrates And Shimmy's At 50 MPH

Check the drive shaft as stated. I would check the wheel bearings and repack them also.
__________________
1971 LWB Custom, 6.0LS & 4L80E, Speedhut.com GPS speedometer & gauges with A/C. 20" Boss 338's Grey wheels 4 wheel disc brakes. My Driver
Seeing the USA in a 71


Upstate SC GM Truck Club
2013,14 and 2016 Hot Rod Pour Tour


http://upstategmtrucks.com/



Get out and drive the truck this summer and have some fun!
It sucks not being able to hear!

LWB trucks rule, if you don't think so measure your SWB!
After talking to tech support at Air Lift I have found out that the kit I need is 60811. Per the measurements I gave them. Ride height of truck inside spring and inside diameter of springs.
Andy4639 is offline   Reply With Quote
Old 03-31-2009, 02:41 PM   #5
67ChevyRedneck
Hittin E-Z Street on Mud Tires
 
67ChevyRedneck's Avatar
 
Join Date: Nov 2004
Location: Greenville, SC
Posts: 23,090
Re: Truck Vibrates And Shimmy's At 50 MPH

My wife's corolla develops this problem a couple times a year when the tire pressure gets to low, the wheel vibrates really bad, air 'em up and the vibration is gone. If it's been sitting for a long time, check the tire pressure. Could be that simple.
__________________
Jesse James
1967 C10 SWB Stepside: 350/700R4/3.73
1965 Ford Mustang: 289/T5-5spd/3.25 Trac-Loc
1968 Pontiac Firebird: Project Fire Chicken!
2015 Silverado Double Cab 5.3L Z71
2001 Jeep Wrangler Sport 4.0L 5spd
2020 Chevrolet Equinox Premium 2.0L Turbo
2011 Mustang V6 ~ Wife's ride
American Born, Country by the Grace of God
1967 CST Shop Truck Rebuild!
My 1967 C-10 Build Thread
My Vintage Air A/C Install
Project "On a Dime"
Trying my hand at Home Renovation!
1965 Mustang Modifications!

Last edited by 67ChevyRedneck; 03-31-2009 at 02:41 PM.
67ChevyRedneck is offline   Reply With Quote
Old 03-31-2009, 03:07 PM   #6
GOPAPA
Registered User
 
GOPAPA's Avatar
 
Join Date: Oct 2007
Location: Nampa Idaho
Posts: 7,553
Re: Truck Vibrates And Shimmy's At 50 MPH

My son first thought a wheel droped a wieght but when he had them balanced they were good and at that time they were checked for air loss..
He also said he got under it and shook all parts including the drive line and found no wobbles.
I suppose that the carrier bearing might not tell you this ,,and only under high speed show up..
How do you go about proving that the carrier bearing is good or bad ?
GOPAPA is offline   Reply With Quote
Old 03-31-2009, 03:22 PM   #7
El Jay
Gone to greener pastures
 
Join Date: May 2007
Location: Gateway to the Delta
Posts: 7,354
Re: Truck Vibrates And Shimmy's At 50 MPH

Larry,
You might check the U-joints too.
I'm not sure how to explain it, but I'll give it a good soldierly try.
It could be that they're "tight" and not "bending" like they're supposed to. So you may want to give them a good shot of grease & maybe that'll free 'em up, if that's the problem.
But, if they've reached that stage, they're probably junk anyhow.

Do you happen to know a drive shaft guy that could check the balance on the drive shaft?

Just some ruminations on my part.

LJ
__________________
'69 Chevy 1/2 T LWB Stepper: Daily Beater
'72 GMC 3/4 T Fleet: Another Daily Beater
'72 Plymouth Gran Coupe: ?


"Ah women. They make the highs higher and the lows more frequent." Friedrich Nietzsche

"Never kick a fresh turd on a hot day." Harry S. Truman

GUN CONTROL: Never having to say, "I missed you."

Always fire two warning shots into your attacker's chest area before putting a bullet between his eyes. Paraphrased from Louis Awerbuck
El Jay is offline   Reply With Quote
Old 03-31-2009, 03:37 PM   #8
GOPAPA
Registered User
 
GOPAPA's Avatar
 
Join Date: Oct 2007
Location: Nampa Idaho
Posts: 7,553
Re: Truck Vibrates And Shimmy's At 50 MPH

Quote:
Originally Posted by El Jay View Post
Larry,
You might check the U-joints too.
I'm not sure how to explain it, but I'll give it a good soldierly try.
It could be that they're "tight" and not "bending" like they're supposed to. So you may want to give them a good shot of grease & maybe that'll free 'em up, if that's the problem.
But, if they've reached that stage, they're probably junk anyhow.

Do you happen to know a drive shaft guy that could check the balance on the drive shaft?

Just some ruminations on my part.

LJ
thanks El Jay ,, any of those sugggestions sound plosible and I will call him and bring them up to him.. the grease in the U-Joints might be what is missing as ,, it has been sitting through a summer and fall and winter out side,,
GOPAPA is offline   Reply With Quote
Old 03-31-2009, 03:52 PM   #9
68caliRat
Need a bigger hammer..
 
Join Date: Feb 2007
Location: Escondido,CA.
Posts: 280
Re: Truck Vibrates And Shimmy's At 50 MPH

How recent was the tire balance? Before or after the shimmy and vibration. Mine did the same thing and I couldn't figure out for the life of me why. Then one day I was trying to run an errand in the truck (even with the shimmy) and BLAM! my front tire exploded. Then it all came back to me. A friends Suburban did the same thing with a rear wheel on a trip we made to Buttonwillow CA. a few years back. Bad tires on both.
__________________
1968 GMC 3/4 LWB fleetside Custom Camper
2018 Silverado High Country 2500HD Duramax 4X4
68caliRat is offline   Reply With Quote
Old 03-31-2009, 04:17 PM   #10
cdowns
Senior Member
 
cdowns's Avatar
 
Join Date: Jan 2003
Location: daytonabeach
Posts: 22,956
Re: Truck Vibrates And Shimmy's At 50 MPH

rechecking wheel balance and that lugnuts are tight on all four would b first on my list followed by inspection of monting hardware of the control arms, then checking the motor mounts ,driveshft ujoints and carrier bearing, i'd also check that the front crossmember is securly fastened to the frame, ball joints tierod ends etc
__________________
71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane

MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF

DONT BELIEVE EVERYTHING YOU THINK

TAKE MY ADVISE;I DON'T USE IT ANYWAY
cdowns is offline   Reply With Quote
Old 03-31-2009, 06:55 PM   #11
NGN
Registered User
 
NGN's Avatar
 
Join Date: Nov 2001
Location: Old Bridge,NJ
Posts: 838
Re: Truck Vibrates And Shimmy's At 50 MPH

I would also check the rear , loose u-bolts and worn perches (egg shape bolt holes ) traling arms and it's parts and all thats been mention already
NGN is offline   Reply With Quote
Old 03-31-2009, 07:11 PM   #12
cparman
sharp as a marble
 
Join Date: Jan 2007
Location: atlantic beach,florida
Posts: 1,082
Re: Truck Vibrates And Shimmy's At 50 MPH

drive the truck at the speed it shakes. Ask yourself, " where do I feel the vibration? Is it in the steering wheel? Or do I feel it in the seat of my pants. After what you have tried, I would think it is a drivetrain problem. If you replaced the whole front clip, I wonder if something is in a bind? Maybe like someone else posted is the carrier bearing shoved back?
I would think this is a trial and error thing, and when you find it, you will go " why did I not think of that first ". I would loosen up the motor mounts, and the trans mount, wiggle the motor and trans, and pay close attention to what happens when you loosen the bolts. Did the motor/trans move? Get everything where you know it should be, and then drive the truck.
YA KNOW IT KIND OF LOOKS LIKE LONGHORN MANS BURB WITH THE NEW CLIP ON IT!!!
cparman is offline   Reply With Quote
Old 03-31-2009, 07:18 PM   #13
mr48chev
Registered User
 
mr48chev's Avatar
 
Join Date: Jul 2007
Location: Toppenish, WA
Posts: 15,708
Re: Truck Vibrates And Shimmy's At 50 MPH

All good suggestions.
As he changed the front clip and it vibrates afterwards what else did he change?
Reason for changing front clip? If it got in a wreck there may be a bent piece in the suspension or steering.

As the others have said I'd check the balance on the wheels again but I would also check=
For and out of round tire or one with a broken belt.
For a gob of dirt/mud inside of one of the rims.

If he changed a drum lately, I have seen at least one drum that was so far out of balance new out of the box that it couldn't be run.

I'd try to find someone with an on the car/truck spin balancer that could spin the wheels on the truck to try and find the vibration that way.
If it doesn't have posi you can jack one rear wheel up at a time and run it up in gear to see if either of the rear wheels are the problem. You should be able to check the driveshaft at the same time too.

When I was doing front end and brake work on a daily basis I ran into more than one guy who didn't think that the rear tires could cause his vibration as they were on the rear.

Last edited by mr48chev; 03-31-2009 at 07:19 PM.
mr48chev is offline   Reply With Quote
Old 03-31-2009, 07:24 PM   #14
clos69
Its Topless Season!!!!
 
clos69's Avatar
 
Join Date: Jul 2007
Location: fort worth, tx
Posts: 1,657
Re: Truck Vibrates And Shimmy's At 50 MPH

Check you crossmember bolts that are bolted to the frame...I had the same problem until I retighten them.
__________________
-Carlos-
The of America

1967 SWB Custom C-10 (Celeste)

Join the Patina Club
clos69 is offline   Reply With Quote
Old 03-31-2009, 07:37 PM   #15
cparman
sharp as a marble
 
Join Date: Jan 2007
Location: atlantic beach,florida
Posts: 1,082
Re: Truck Vibrates And Shimmy's At 50 MPH

Mr48chevy, I used to have a spin balancer back in the day, MAN what a great piece of equipment!! Balanced everything that rotated at every corner. I still have a scar on my arm from getting too close to the tire that was spinning 60+. Wonder if you could still buy one of those -----
cparman is offline   Reply With Quote
Old 03-31-2009, 08:38 PM   #16
BluTrukker
BOHICA
 
BluTrukker's Avatar
 
Join Date: Mar 2008
Location: Stewartville, MN
Posts: 440
Re: Truck Vibrates And Shimmy's At 50 MPH

It have your answer. It isn't a cheap fix, but I would bet it is your tires. I had the exact same issue with my 91 chev. I had cheap old tires, and I let it sit for a couple months and then it developed a shimmy. The belts went bad in the tires. If you can borrow some tires from somebody for a test drive, then you can rule out bad tires.
__________________
Trying to save someone from their own stupidity is like teaching a pig to dance. It is a waste of your time, and it annoys the pig!
BluTrukker is offline   Reply With Quote
Old 03-31-2009, 08:53 PM   #17
ChevLoRay
Old Skool Club
 
ChevLoRay's Avatar
 
Join Date: Jun 2001
Location: Benton, AR "The Heart of Arkansas"
Posts: 10,880
Re: Truck Vibrates And Shimmy's At 50 MPH

If the tires have flat spots, they should go away when they get warmed up. If not, then spinning them on a balancer should allow you to look at them and see the flat spot. If you can "help" then you can hold something in a fixed position and see if there is a fluctuation as it rotates. It doesn't have to be powered, just turning slowly and checking for an out-of-round state.

As for the driveline, u-joints that have rusty bearings could be the issue. As stated earlier, a tight u-joint will cause a vibration. It doesn't take much rust to tighten up the clearances within the cross and roller.
__________________
Member Nr. 2770

'96 GMC Sportside; 4.3/SLT - Daily driven....constantly needs washed.

'69 C-10 SWB; 350/TH400 - in limbo

The older I get, the better I was.
ChevLoRay is offline   Reply With Quote
Old 04-01-2009, 06:27 AM   #18
Blazer1970
Registered User
 
Blazer1970's Avatar
 
Join Date: Dec 1999
Location: Old Mission, MI, USA
Posts: 2,507
Re: Truck Vibrates And Shimmy's At 50 MPH

Quote:
Originally Posted by BluTrukker View Post
It have your answer. It isn't a cheap fix, but I would bet it is your tires. I had the exact same issue with my 91 chev. I had cheap old tires, and I let it sit for a couple months and then it developed a shimmy. The belts went bad in the tires. If you can borrow some tires from somebody for a test drive, then you can rule out bad tires.
Good advice. This type of vibration at a certain speed is almost always a tire problem. Balancing often will not help.
__________________
Tim
Blazer1970 is offline   Reply With Quote
Old 04-01-2009, 10:48 AM   #19
special-K
Special Order

 
special-K's Avatar
 
Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,851
Re: Truck Vibrates And Shimmy's At 50 MPH

You say it was good for awhile after the accident and the tires were checked for balance.And,the balance was good?Maybe something worked loose since it`s droiven after the accident.The shimmy is felt in the steering wheel,as in more than just a transfered vibration.More like the wheel wants to rock back and forth.Did you check side to side play as well?It could be the tie rod ends.Ball joints will make it bounce and that`s how a bad or loose bearing feels,like the tire`s bouncing.
I`d try on some other tires.Can you borrow some?Try rotating and see if the vibration moves or stops.
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed"

GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project)
GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling)
Tim

"Don't call me a redneck. I'm a rough cut country gentleman"

R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~
special-K is offline   Reply With Quote
Old 04-01-2009, 07:23 PM   #20
GOPAPA
Registered User
 
GOPAPA's Avatar
 
Join Date: Oct 2007
Location: Nampa Idaho
Posts: 7,553
Re: Truck Vibrates And Shimmy's At 50 MPH

I will see him tonite and let him know all the suggestions from you all.. thanks papa
GOPAPA is offline   Reply With Quote
Old 04-01-2009, 09:43 PM   #21
norske
Registered User
 
Join Date: Dec 2008
Location: Austin, MN
Posts: 117
Re: Truck Vibrates And Shimmy's At 50 MPH

How about running it at 50 mph in a lower gear? Would that separate a tire problem from everything else ie: speed vs. rpms?
norske is offline   Reply With Quote
Old 04-01-2009, 11:16 PM   #22
72BLUZ
Registered User
 
72BLUZ's Avatar
 
Join Date: Nov 2006
Location: lafayette, ga.
Posts: 832
Re: Truck Vibrates And Shimmy's At 50 MPH

around our shop most vibrations that can be driven thru are tire related
__________________
Freedom is never more than one generation away from extinction. We didn't pass it to our children in the bloodstream.
It must be fought for, protected, and handed on for them to do the same.... Ronald Reagan
72BLUZ is offline   Reply With Quote
Old 04-02-2009, 07:53 AM   #23
A.P.
Black 72 Chevy
 
A.P.'s Avatar
 
Join Date: May 2002
Location: Los Angeles, California
Posts: 662
Re: Truck Vibrates And Shimmy's At 50 MPH

Check your shock absorbers.
__________________
72 Chevy, SWB, 350engine, TH400
A.P. is offline   Reply With Quote
Old 04-02-2009, 08:07 AM   #24
special-K
Special Order

 
special-K's Avatar
 
Join Date: Nov 2004
Location: Mt Airy, MD
Posts: 85,851
Re: Truck Vibrates And Shimmy's At 50 MPH

Definately look at the tires.Even if you don`t have another set laying around,rotating with move the problem and produce a different result.A bad tire up ront will exaggerate front end wear and will be felt in the steering wheel more than if it`s on the rear.On the rear you`ll notice the rear bed corner vibrating or hopping more than the other side.
__________________
"BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed"

GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project)
GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling)
Tim

"Don't call me a redneck. I'm a rough cut country gentleman"

R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~
special-K is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not 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

Forum Jump


All times are GMT -4. The time now is 10:27 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com