Vibration

Mudeblue

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1965 Sport Fury - Have a chronic vibration for several years sometimes slightly at low speeds which disappears between 30 - 75. At 70 and up, terrible vibration and have to reduce speed. Can't identify exact source.

Over the years, I have had the transmission rebuilt5, which was relooked at, straightened the drive shaft, which repair shop said was bent, replaced both back axles which again two different repair shops claimed were bent on different occasions and I just had different rims and brand new tires put on car, yesterday. Even had the motor mounts checked along the way.

I am now at the point that there might be a possibility that I may have a fly wheel or torque converter out of balance. However, this should have been identified during the transmission rebuild and recheck.

I am lost and would appreciate any ideas.
 
what about suspension in the front? any bushings or ball joint work?

Alignment?
 
1965 Sport Fury - Have a chronic vibration for several years sometimes slightly at low speeds which disappears between 30 - 75. At 70 and up, terrible vibration and have to reduce speed. Can't identify exact source.

Over the years, I have had the transmission rebuilt5, which was relooked at, straightened the drive shaft, which repair shop said was bent, replaced both back axles which again two different repair shops claimed were bent on different occasions and I just had different rims and brand new tires put on car, yesterday. Even had the motor mounts checked along the way.

I am now at the point that there might be a possibility that I may have a fly wheel or torque converter out of balance. However, this should have been identified during the transmission rebuild and recheck.

I am lost and would appreciate any ideas.
i would get a second opinion on the driveshaft. any good shop doing drivelines would have made a new shaft and balanced it. never heard of straightening one with any success. but that doesn't mean it cant be done i guess. just my thought. best of luck to you .
 
what about suspension in the front? any bushings or ball joint work?

Alignment?
All replaced when I bought the car in 1989 and have less than 10,000 miles ITD. However, when they were replaced, I caught the mechanic pounding on the torsion bars with a sledge hammer which came to an abrupt stop!
 
i would get a second opinion on the driveshaft. any good shop doing drivelines would have made a new shaft and balanced it. never heard of straightening one with any success. but that doesn't mean it cant be done i guess. just my thought. best of luck to you .
Just had new disc brakes put in by Arizona Differential, who also put in one of the two new axles, but it is worth a try.
Thanks
 
All replaced when I bought the car in 1989 and have less than 10,000 miles ITD. However, when they were replaced, I caught the mechanic pounding on the torsion bars with a sledge hammer which came to an abrupt stop!
Yikes!
I know that some are hard to remove and there's a Mopar tool for that but I have never had to pound them out..
 
All replaced when I bought the car in 1989 and have less than 10,000 miles ITD. However, when they were replaced, I caught the mechanic pounding on the torsion bars with a sledge hammer which came to an abrupt stop!


What about the lower bushings? I've heard this is an often overlooked part..
 
What about the lower bushings? I've heard this is an often overlooked part..
I will give it a shot but I believe that these were also replaced in 1989. That was almost 30 years ago and my mind can't remember all the details! May have to take the car in and have the whole front end re-inspected!
 
1965 Sport Fury - Have a chronic vibration for several years sometimes slightly at low speeds which disappears between 30 - 75. At 70 and up, terrible vibration and have to reduce speed. Can't identify exact source.

Over the years, I have had the transmission rebuilt5, which was relooked at, straightened the drive shaft, which repair shop said was bent, replaced both back axles which again two different repair shops claimed were bent on different occasions and I just had different rims and brand new tires put on car, yesterday. Even had the motor mounts checked along the way.

I am now at the point that there might be a possibility that I may have a fly wheel or torque converter out of balance. However, this should have been identified during the transmission rebuild and recheck.

I am lost and would appreciate any ideas.
Does this happen under acceleration. Shift into neutral when this occurs does it change or stop. Does it come from the front or rear. Do you feel it in the steering wheel or floor pan. Appears to be speed sensitive to speed. Check drive shaft for run out and stiff u joints. If found correct first. Check tires for irregular wear, shape and balance. Inspect front K member for cracks and worn or loose mounts and bolts. Lastly check all steering linkage ball joints and control arm bushings. Report what you find.
 
My brother's '73 Plymouth had a pronounced vibration at certain higher speeds after rebuilding the engine/driveline. Did a lot of web surfing and one of the things often mentioned is the relationship angle between the driveshaft and the back of the trans and the driveshaft angle and the rear-end pinion. If these are not correct, it will give you a vibration at certain speeds.

With my brother's car, it was found that I had somehow flipped the transmission mount or installed it backwards or something. It was corrected and most of the vibrations was taken out.

He has yet to have the driveshaft checked - which it may be, or it could be the pinion angle as I installed a rear axle assembly and rear sway bar out of a 1977 car. He says its not too bad now and only occurs at a certain speed, so he has not done any more with it. I never checked the pinion angle, nor knew about this, but they do make shims that can be installed under the axle pads where your U-bolts are found and this can tilt the pinion up just a few degrees. So driveshaft & pinion angle can produce a vibration as certain speeds if it is way off from spec.

I don't recall what the factory angles call for and maybe some one here might be able to chime in better on this than me.
 
Back in the late '80's bought a '66 Satellite Vert with a 440/4 speed(original 361/4 speed)and had a terrible vibration. Local shop tried to balance it to no avail. Finally figured it out on my own, drive shaft was too short. had a new one made and problem solved. Changed the seal in the tail shaft as the drive shaft was beating around.
 
1965 Sport Fury - Have a chronic vibration for several years sometimes slightly at low speeds which disappears between 30 - 75. At 70 and up, terrible vibration and have to reduce speed. Can't identify exact source.

Over the years, I have had the transmission rebuilt5, which was relooked at, straightened the drive shaft, which repair shop said was bent, replaced both back axles which again two different repair shops claimed were bent on different occasions and I just had different rims and brand new tires put on car, yesterday. Even had the motor mounts checked along the way.

I am now at the point that there might be a possibility that I may have a fly wheel or torque converter out of balance. However, this should have been identified during the transmission rebuild and recheck.

I am lost and would appreciate any ideas.
Left out rear trans mount. Have found many w/ rubber breaking down and sagging.
 
1965 Sport Fury - Have a chronic vibration for several years sometimes slightly at low speeds which disappears between 30 - 75. At 70 and up, terrible vibration and have to reduce speed. Can't identify exact source.

Over the years, I have had the transmission rebuilt5, which was relooked at, straightened the drive shaft, which repair shop said was bent, replaced both back axles which again two different repair shops claimed were bent on different occasions and I just had different rims and brand new tires put on car, yesterday. Even had the motor mounts checked along the way.

I am now at the point that there might be a possibility that I may have a fly wheel or torque converter out of balance. However, this should have been identified during the transmission rebuild and recheck.

I am lost and would appreciate any ideas.

If you have a flywheel or torque converter that is out of balance, it will vibrate regardless of whether the car is in gear or not. Try running the engine up to about 3000 rpm, do you have a vibration? Frequent cause of severe vibration is the installation of a weighted torque convertor on an application that does not require it. Do you know if this engine was ever rebuilt? Some forged steel crankshafts have weighted convertors, cast steel cranks do not. (Internal vs external balancing) Check you oil filter for metal shavings, bearing material in the oil filter is indicative of a main line vibration, possibly from a badly balanced engine due to mismatched components, failing crankshaft or a bad harmonic balancer. Check your flex plate for cracks by removing the inspection cover.

Check your harmonic balancer, if you can move the outer ring of the balancer side to side or back and forth by hand, the rubber holding it together is shot; the unit is defective and needs to be replaced/rebuilt. Try disconnecting belt driven components to see if that effects the vibration, a bent water pump shaft can raise all kinds of hell.

Try jacking up the rear of the car, block the front wheels and run the car in drive to see if you can duplicate the the vibration you feel on the road. You could have a bent or failing cone in the differential carrier. Look for any signs of drive line hopping or other signs of misalignment. Drive train components to the rear of the engine that are vibrating will usually have noise associated with whatever is causing the problem, while the rear wheels are up listen for strange noises with the car in gear.

Dave
 
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If you have a flywheel or torque converter that is out of balance, it will vibrate regardless of whether the car is in gear or not. Try running the engine up to about 3000 rpm, do you have a vibration? Frequent cause of severe vibration is the installation of a weighted torque convertor on an application that does not require it. Do you know if this engine was ever rebuilt? Some forged steel crankshafts have weighted convertors, cast steel cranks do not. (Internal vs external balancing) Check you oil filter for metal shavings, bearing material in the oil filter is indicative of a main line vibration, possibly from a badly balanced engine due to mismatched components, failing crankshaft or a bad harmonic balancer. Checkyour flex plate for cracks by removing the inspection cover.

Check your harmonic balancer, if you can move the outer ring of the balancer side to side or back and forth by hand, the rubber holding it together is shot; the unit is defective and needs to be replaced/rebuilt. Try disconnecting belt driven components to see if that effects the vibration, a bent water pump shaft can raise all kinds of hell.

Try jacking up the rear of the car, block the front wheels and run the car in drive to see if you can duplicate the the vibration you feel on the road. You could have a bent or failing cone in the differential carrier. Look for any signs of drive line hopping or other signs of misalignment. Drive train components to the rear of the engine that are vibrating will usually have noise associated with whatever is causing the problem, while the rear wheels are up listen for strange noises with the car in gear.

Dave
Dave: Run the engine up to 4,000 RPM in neutral and park with no vibration. Has to be from the tranny back? Think I will get the drive shaft and differential checked as a start.
 
Dave: Run the engine up to 4,000 RPM in neutral and park with no vibration. Has to be from the tranny back?

Very likely. When you were driving the car, did you feel vibration on the steering wheel or on your butt from the seat? Steering wheel vibration would indicate front suspension components causing the issue. Vibration felt coming from the seat usually indicates a transmission, drive line or rear end problem. Try doing the other tests with the car jacked up.

Dave
 
Very likely. When you were driving the car, did you feel vibration on the steering wheel or on your butt from the seat? Steering wheel vibration would indicate front suspension components causing the issue. Vibration felt coming from the seat usually indicates a transmission, drive line or rear end problem. Try doing the other tests with the car jacked up.

Dave
All over "Shake it up baby" so to speak! Feels like something is about to fly apart.
 
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