My 1968 Plymouth Sport fury

[1968 fury3 man:-)]

Hi guys I have a few questions for guys that have a car like mine I have a weird shake / vibration that comes in at 70 mph is this normal I've replaced everything under the sun if you name it I've replaced it can't figure it out all the front suspension is brand new universal joints are all brand new I can't pin it down but also I'm looking for seats bucket seats and I'm looking for console and shifter linkage and rods if anybody can help me be gratefully appreciated

 

[Boydsdodge]

Pinion angle comes to mind. How is your car lifted?

 

[Pax2001]

agree with Boydsdodge, but have you altered or replaced the drive shaft? Is it balanced correctly?
I'm going to skip the obvious wheel balance thing.
Higher speeds affect different things than higher rpm's do.

 

[Boydsdodge]

Hi guys I have a few questions for guys that have a car like mine I have a weird shake / vibration that comes in at 70 mph is this normal I've replaced everything under the sun if you name it I've replaced it can't figure it out all the front suspension is brand new universal joints are all brand new I can't pin it down but also I'm looking for seats bucket seats and I'm looking for console and shifter linkage and rods if anybody can help me be gratefully appreciatedView attachment 457409 View attachment 457409

What type of vibration are you feeling? Seat, steering wheel, throttle pedal, can't see out the rear view mirror?

 

[mrfury68]

Transmission mount? BTW Love the color of your formal top. That was the same color as my dad's '68 Fury III sedan that I grew up in.

 

[HWYCRZR]

Likely driveshaft out of balance or one of your yokes bent from an aggressive hammer. My vibration was at 80 mph.
I had a couple of dings in it. They straightened it and balanced plus straighten the yoke. No vibration up to 110.
I get a little carried away with perfection sometimes but here is the thread.
Drive Line Angle will drive you crazy

 

[CBODY67]

I'm suspecting the pinion angle for that elevated ride height. There are some shims in the aftermarket to reposition/tilt the rear axle on the leaf springs.

 

[69PHOENIX]

I think the term is Phasing.
Look up the Term Tail Shaft Phasing, Might be Helpful.
Also Interesting!
Tony.M

 

[57fury440]

Make sure the transmission bolts are all tight. Is the engine smooth when you rev it up?

 

[1968 fury3 man:-)]

Thanks guys I just seen every one's posts and I am thinking drive shaft pinion angle also I have air shocks with extensions

 

[1968 fury3 man:-)]

Yes engine is smooth

 

[1968 fury3 man:-)]

It feels like a vibration that I can fill in my seat and steering wheel

 

[1968 fury3 man:-)]

I replaced up and lower control arm bushings upper and lower ball joints front wheel bearings the drive shaft seems to be a two-piece before the rear universal joint looks to be like the drive shaft is pressed into itself with rubber Cushing dampener or something like that it couldn't be that right

 

[MarkLevi]

Another suggestion if you don't find it elsewhere: Check that your steering sector is "tight" to the frame - those mount bolts can loosen....

Thanks
Mark