The shaking 65 coronet

[65coronet440]

Alright, this has gone on for too long, i have officially wasted a summer trying to locate this issue...

Quick back ground... Slid into a ditch 2 years ago...hydroplayned.. no body damage....1 bent rim.........repaired...

Recent disc brake swap in the front.. new spindles, ball joints, tie rods, idler arm, shocks, power booster, master cylinder,drive shaft, alternator, water pump, hoses, coil....

Issue...

I have a very aggressive shudder/shake when driving.. it seems to be rpm specific....usually at about 1800 rpm to 2500 rpm... if i give it some gas during the shudder it will smooth out a little bit... When i shakes, the gas pedal vibrates, and the floor underneath my feet does as well...

I was thinking of rotating the driveshaft 180 but i didnt have this problem with the shudder last year...

Any help????

 

[Red63440]

Check the universals and I would start witrh the one in the front since it seems that where most of the vibration is coming from.

 

[Dodge33]

It sound's to me, like a driveshaft too........ but like Red said check the universal joint's first. Got a question for you? Ok............ you said you replaced the driveshaft in the car, was the reason being the original one was missing, bent, or too rusty, or?? Did you have this new shaft custom made? If you did, you may want to take it to a different drivetrain shop, and have them put it on a lathe and have it checked with a dial indicator for trueness and balance!! It just seem's like a football shaped driveshaft. I hope this help's. Good Luck! Dodge33

 

[Histoy]

You might also check the condition of the transmission mount.

 

[Ron 73]

The bent rim was repaired, have you got another just for giggles to try? This a shot in the dark here but once i had a similar problem and the short of it was I didn't have one of my wheel bearings quite tight enough.. Like i said its a shot in the dark but ya never know. More RPM it just settled the issue some because the wheel was turning faster is all, an illusion of it wobbling a bit faster to make me think it was smoother.

 

[brandon64]

This is what I have done in the past. Jack up the back end so that the back wheels are off of the ground. Make sure the car is blocked very well. start it, and put in drive and accelerate to the RPM that the vibration occurs. If it does, then your vibration issue is in the drive-train or rear wheels. if it goes away, then it's in the front. This will narrow down your search. If it's in the front it will be a shot in the dark as to what is the problem, but if its in the rear you can have someone hold the gas pedal at the RPM that the vibration occurs and crawl under the car and look and listen for something out of place. good luck.

 

[Big Jim]

Little easier way than Brandon's (not necessarily better) when you get the shudder/vibration, do you feel it in thee steering wheel or through the seat? Seat usually indicates drivetrain, steering wheel points to front end...

 

[moparsteve636]

Do you have the flange on the front of shaft?(64 & earlier) possible point of your vibration!Rebuild kits are available,not cheap though!

 

[dryheat]

If the vibration is specific to engine speed and not vehicle speed I would think that the drive shaft is not the issue.

Does it vibrate in any gear at the engine RPM's you mentioned?

 

[tommy smith]

Alright, this has gone on for too long, i have officially wasted a summer trying to locate this issue...

Quick back ground... Slid into a ditch 2 years ago...hydroplayned.. no body damage....1 bent rim.........repaired...

Recent disc brake swap in the front.. new spindles, ball joints, tie rods, idler arm, shocks, power booster, master cylinder,drive shaft, alternator, water pump, hoses, coil....

Issue...

I have a very aggressive shudder/shake when driving.. it seems to be rpm specific....usually at about 1800 rpm to 2500 rpm... if i give it some gas during the shudder it will smooth out a little bit... When i shakes, the gas pedal vibrates, and the floor underneath my feet does as well...

I was thinking of rotating the driveshaft 180 but i didnt have this problem with the shudder last year...

Any help????

i bought a nice turbo regal and knew it had q-panel damage before i purchased car. it had some viberation in it at certain speeds. i gave it to my son on h-school grad. he never noticed it. we lived in diff. state,so i never fixed or thought much about it just every once in a while. but did come to the conclusion that the axle probibly got bent,since thats all that was left to check. since you ran off road this could have happened. its worth checking if every thing else has been fixed or changed.have some one follow you and see if wheels runs true,and check and see if it runs a bit side ways. clean sides of axle flange and get magnetic base with travel indicater to check to see if axle runs true. hope this possibly helps. tommy

 

[NOSTRT980]

did you replace the tire or just have the rim repaired?

 

[bfury]

Driveshaft and more

I had a similar vibration in my '63 Fury. Heres what I found, trans mount rubber in 2 pieces, 3 bolts holding the trans to the engine, trans mount to body had the outside ears cut off and the drive shaft slip yoke was not in the tailshaft enough. The car has a '65 trans and drive shaft from something. I replaced the trans mount, replced the crossmember mount and put in the rest of the trans to engine bolts as well as replaced both universals. It's not entirely gone because I believe I still have the driveshaft length issue but it is very livable now. I guess you never know what you will find in a 48 year old car!

 

[Dodge 330]

Again, sounds like a driveline vibration.

Try a couple of hoseclamps on the driveshaft as makeshift weights and move them around to see if you can make any difference.

 

[65coronet440]

These are all great suggestions... i did another road test.. and was more aware of the vibration...it also takes place in PARK/Neutral....So that would eliminate the driveshaft and bent axle right?... I jacked up the car after i shut it off and noticed that the trans mount looked a little off.. looked to be in good shape though..

The Rim was Replaced.. for the earlier posts... not repaired...sorry.......

The driveshaft was repalced with a aftermarket one after we snapped it in 2 at the track... it took out the tailshaft of the transmission.. It was orderer, And Balanced from the manufactor apparently.. the universals still look new under neath....

 

[65coronet440]

If the vibration is specific to engine speed and not vehicle speed I would think that the drive shaft is not the issue.

Does it vibrate in any gear at the engine RPM's you mentioned?

Usually yes it is more rpm speed... i get paranoid taking it out for anything longer than 5 min to diagnois because its a bad shake...The Dash shakes my glove box open.. It is felt more in the steering wheel, dash and my floor shifter...... nothing in the brake pedal.... gas pedal yes....

 

[moperformance]

Flywheel/flex plate bolts?

 

[SirSixPack]

flywheel/flex plate bolts?

x 2

 

[splicer]

In post #14, it looks like you've said that the vibration is there in Park/Neutral.

If the car is stationary, then your problem is limited to engine-torque convertor and transmission components only...Drive shaft and rims are eliminated..

Splicer

 

[bfury]

6 pak Crank?

It's possible that you a 6 pak crank (which is externally balanced rather than internally like a forged crank)and that requires a special flex plate that you can get from B&M. It has a piece out of it to make up for balance. It is also possible that is a damper problem since a cast crank has weight added or removed to help external balance. Or you could have a combination of all these. It could also be a bent flex plate. Also a balance weight may have been on the factory converter that flew off. If the problem started after a converetr change these things should be checked. IE proper balancer / flexplate with the crank.

 

[mgriffith]

Or it could be something as simple as a faulty alignment or balljoints.