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 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 03-26-2010, 09:05 PM   #1
jimgmc
Registered User
 
jimgmc's Avatar
 
Join Date: Dec 2009
Location: CASTAIC, CA
Posts: 43
Question Vibration problems

For some reason i cant figure out what is going on with my truck. I rebalanced my driveline and all for wheels, but for some odd reason after going over say 25mhp i get this vibration on the truck.

Last edited by jimgmc; 03-26-2010 at 09:06 PM.
jimgmc is offline   Reply With Quote
Old 03-26-2010, 09:27 PM   #2
ChevyTech
Registered User
 
Join Date: May 2004
Location: Minnesota
Posts: 4,621
Re: Vibration problems

Tire vibration because of balance shows up most in the 55 to 60 MPH speed range.

Drive shaft balance problems usually show up around 45 MPH.

For a problem that you can feel at 25 MPH you should be looking for a bent wheel, a tire with a bulge or belt problem, or a bent axle.

What year is the vehicle?
What vehicle?
Is it a four wheel drive truck?
Have you tried running it on jack stands?
Have you checked the U joints?
ChevyTech is offline   Reply With Quote
Old 03-26-2010, 09:56 PM   #3
jimgmc
Registered User
 
jimgmc's Avatar
 
Join Date: Dec 2009
Location: CASTAIC, CA
Posts: 43
Re: Vibration problems

Its a 1999 gmc 2500 2wd 350 auto not sure on rear ratio. When i bought the truck it had steel wheels and it did the same thing. The u joints look good. Would warped discs cause that?
jimgmc is offline   Reply With Quote
Old 03-26-2010, 10:22 PM   #4
ChevyTech
Registered User
 
Join Date: May 2004
Location: Minnesota
Posts: 4,621
Re: Vibration problems

I don’t think it is the rotors.

I would put the back up on jack stands, with the truck running in neutral (NOT park), and the wheels should spin enough, and at a good speed, to see if an axle is bent. Have someone sit in the driver seat for safety.
ChevyTech is offline   Reply With Quote
Old 03-26-2010, 10:30 PM   #5
jimgmc
Registered User
 
jimgmc's Avatar
 
Join Date: Dec 2009
Location: CASTAIC, CA
Posts: 43
Re: Vibration problems

Thanx ill try that this weekend. This vibration is really getting on my nerves.

Last edited by jimgmc; 03-26-2010 at 10:31 PM.
jimgmc is offline   Reply With Quote
Old 03-27-2010, 01:34 PM   #6
ChevLoRay
Old Skool Club
 
ChevLoRay's Avatar
 
Join Date: Jun 2001
Location: Benton, AR "The Heart of Arkansas"
Posts: 10,880
Re: Vibration problems

Just to add my $.02 worth....rotors on disc brakes that have any irregularity don't necessarily show up until you are on the brakes. My personal experiences include brakes that were heated up on a downhill run. That added to the effect...a pulsating brake pedal and a shimmy in the front end that quit when I got off of the brakes. My wifes' Lexus and my '00 Tundra both had that to happen to them.

Great thing is that my GMC has not been afflicted by any brake issues....short of needing pads and the rotors turned.
__________________
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 03-29-2010, 09:53 AM   #7
GASoline71
"I ain't nobody, dork."
 
GASoline71's Avatar
 
Join Date: Sep 2007
Location: Whidbey Island, Washington
Posts: 8,961
Re: Vibration problems

Well... my 1994 GMC Sierra K1500 has developed a vibration at 40mph... and then at around 60mph. I can feel it through the steering wheel. Not bad, but annoying... and will prolly get worse.

Truck needs brakes all around. The rear brakes are starting to "surge" a little... I'm sure it's uneven drums. I was noticing this vibration about a month ago, and had the tires rebalanced and rotated. Now I can feel it through the steering wheel. So... I'm hoping it's just tires out of balance. I need to take it back to the tire shop, and have them rebalance.

I checked the front end this weekend. No worn ball joints... but one of the tie rods prolly has a little more play in it than it should. Could be contributing to the vibration I feel in the front. I checked drivelines too, and all u-joints appear to be in good shape. No slop either.

Good times... I hate chasing Gremlins... at least it's not electrical... those Gremlins are worse.



Gary
__________________
'cuz chicks dig scars...

My 1972 GMC 1500 Super Custom (Creeping Death) "long term" build thread.

The Rebuild of Creeping Death after the wreck

Quote:
Originally Posted by LONGHAIR View Post
I would never rebuild a 305.
Quote:
Originally Posted by prostreetC-10 View Post
I love using vacuum gauges as part of the carb tuning process. I hook the gauge to the inside of my garbage can and leave it there.
Quote:
Originally Posted by Marv D View Post
Remember Murphys 2nd law of mechanical relationships... "OPPOSING COMPONENTS ATTEMPTING TO OCCUPY THE SAME SPACE, AT THE SAME TIME, GENERALLY END UP OCCUPYING ADJOINING SPACE AT THE BOTTOM OF THE OIL PAN"
Quote:
Originally Posted by cableguy0 View Post
Its cheaper to listen to advice given when you ask for help than it is to ignore everyone and wait for carnage.

Last edited by GASoline71; 03-29-2010 at 09:55 AM.
GASoline71 is offline   Reply With Quote
Reply

Bookmarks

Tags
2500, 2wd, 350 vortec


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 09:19 AM.


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