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Topic: Bad Vibrations... (Read 1017 times) previous topic - next topic

Bad Vibrations...

just new to this , so please be paitient with me...I've had an '88 Cougar LS 5.0 w/AOD since '99, got it from my Dad when he could'nt drive anymore...anyway, it's had a travelling vibration from day one for me...at Hwy speed it will run through the car from front to back/back to front...the steering wheel vibrates up and down along with the dash...i've had 4 different sets of rims & tires on it...checked and replaced every bearing...checked axles for true...it has been suggested that maybe it is Harmonic Balancer or Flywheel....HELP!! Does anyone have any thoughts??

Bad Vibrations...

Reply #1 –
If it's the harmonic balancer or flywheel you should be able to make it happen while sitting in the driveway - just rev the engine to around the same speed (RPM) the vibration happens and see if you get it.

Could be worn or seized U-Joints as well, or a bent or out of balance drive shaft (it's common for the balancing weights to fall off the drive shaft with age)
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Bad Vibrations...

Reply #2 –
Very good suggestions by ThunderChicken

Since you refer to it as a "traveling vibration" I would be checking that Driveline first. New U-Joints both ends and a rebalance. Since the joints are attached to the driveline at both ends take the whole works to a driveline shop and have them go over it. Don't think it would be that expensive.
:birdsmily:   Objects In Mirror Appear to be Loosing  :birdsmily:

Bad Vibrations...

Reply #3 –
Yeah its like $100 to balance a driveshaft.  That really sounds like your problem too.  My 88 is missing a weight on the driveshaft and it kills you to go over 50mph.
One 88

Bad Vibrations...

Reply #4 –
A little trick: If your U-joint's weight is missing and you can still see where it used to be you can reduce the imbalance by putting a large hose clamp on the driveshaft and locating it so that the screw part is where the old weight was. Won't be perfect, but it'll help
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Bad Vibrations...

Reply #5 –
Heh the weight that came off mine was about the size of 3 (American) 50 cent pieces stacked on top of each other.
One 88
 

Bad Vibrations...

Reply #6 –
Thanks for the great tips...she's going in for some exhaust work this week , will check it then!!  All u-joints have been done, just havent checked balance on it!  I do get some of the same vibration at an idle, tried shutting off the engine at hwy speed sat., but it didnt change!!