Bad vibrations...

[Dave145]

Hi everybody,

So my 64 Polara had had a wonderful vibration since I bought it. It's felt in both the steering wheel and front floor, and at all speeds between 40-75, while accelerating, cruising, decelerating, or braking. At 75 the car feels like it's going to explode with how bad the vibration is.

First I replaced the rear u-joint and rebuilt the ball and trunion joint. No change.

Then I changed the 4 year old tires out to tires that are a year old with 1,000 miles on them. No change.

Then I replaced all 4 front bearings and the 2 outer rear bearings. I also rebuilt the brakes at this time. No change.

I then replaced all 4 balljoints. Again, no change.

The shocks are newer (installed by PO and have no receipt but they are shiny). They appear to be el cheapo Monroes.

The tires are balanced with balancing beads. The car they came off of was my '76 Dodge Dart. That car shimmied at 75 also, but the rims had a bit of run-out to them. That car DID NOT vibrate as much as this one does.

So...I'm at a crossroads. What do you think it is? Steering feels tight. Tie rods feel a little notchy if you try to rotate them by hand, but I can't imagine that's setting up a whole car vibration.

Perhaps these rims are junk and seriously bent?

Tension bar bushings? Torsion bar bushings? Control arm bushings?

I don't think it's the rear end or axle, as while cruising I can drop the car into neutral and it still vibrates.

 

[mopar73dge]

What rims are you using?, take the 4 tires and rims to a shop that has a road force balance machine, which puts 1200 to 1400 lbs of force with a wheel on the spinning tire to simulate the on car down force. they will tell you if they are far off balance and bring them in hopefully to the 8lb max of (road force) that is acceptable.
I have four magnum 500 rims new, from wheel vintiques, no one could balance them, they said the rims are bent!, I had vibration after 60 mph, I took them to C& R Auto in Sturbridge MA where I live close to. They said all the tires were way off balance, . Two rims are now at 1 lb force and two at 7lb force. I just did this yeaterday! I put the 7lb rims in the rear and the 1 lb in the front. I drove the car on the highway its perfect! up to 80 mph with no Vibration. Its like a new car... Finally back to how it was when I had the original factory magnum rims..

 

[Dave145]

Currently I'm running the stock steel wheels on it. I know the shop we use to put tires on has a spin balancer, but I don't believe it's a road force balancer.

It seems as if this car was extremely neglected and also lived on some kind of dirt/gravel road, so it wouldn't surprise me if it had a shot rim or two.

 

[mopar73dge]

The road force balancing is the only way to go and the best there is. you will know if it is the rims or a bad belt in a tire... use the process of elimination this would be one test you have not done yet!

 

[furyus]

My question is, does it vibrate sitting still, trans in park, or neutral. By checking it while not moving, eliminates the driveline, tires, etc

 

[Dave145]

It does not vibrate at all while sitting still. That old 318 poly idles smooth as glass! At around 55-65 there is no/minimal vibration as well. But anything outside of that speed range vibrates. At slower speeds, the vibration is only in the wheel and is minor. But as the car speeds up, the vibration does too. You begin to feel it in the floor around 50, then it goes away 55-65, and returns ferociously at 70.

 

[mopar73dge]

out of balance, go to the shop with a road force balance machine

 

[khryslerkid]

Bent or out of balance drive shaft?

 

[furyus]

A wheel, or tire is a shake. Driveline is more of an oscillating rumble. I agree with others. Try to have the tires balanced with a road force balancer. They will need to remove the balancing beads.

 

[MW 413]

I would bet either a bent wheel or out of round tire. Both will show ok balance on a tire balance machine but beat the hell out of you on the road. Driving in and out of the vibration at different highway speeds for either is not unusual.

 

[Dave145]

Sounds like a likely consensus then for rim/tire issue. Now to find a shop with a roadforce balancer!

 

[bschomske]

How about something simple like tranny mount?

 

[Bill Monk]

Sounds like a likely consensus then for rim/tire issue. Now to find a shop with a roadforce balancer!

most dealers have one, most tire stores don't but there is no doubt, that's the way to find or eliminate a tire or wheel issue

 

[Dave145]

I was able to find a shop with a balancer. They are going to look at and balance the tires Saturday.

If that doesn't fix the issue, where would you guys check next? Tie rods?

 

[Jcharger]

Have you ruled out the driveshaft/ mount issues suggested above? I threw a driveshaft weight once and it felt like I was riding on washboards when I hit 60 mph. Also had tire and wheel balance issues, so I can see eliminating those first.

 

[Dave145]

Nowhere on the driveshaft does it look like I lost a weight. I have no reason to believe it to be bent either. I don't think it's mounts, because both motor mounts and the tranny mount look good, plus when revved, the motor does not move upward (had motor mounts let loose in an old truck of mine...engine would jump out at you if you had the hood open and revved the gas). The tranny mount appears solid, and I can pretty much swing myself on the tranny and it doesn't move more than 1/8" Max.

 

[Thunderlugs]

Bring her over..... we can throw her up on the lift ,and have a looksee!!

 

[MW 413]

If all else fails look at the brake drums and make sure you haven't lost a brake drum balance weight. They were spot welded on some drums to get in balance when made new.

 

[Dave145]

Thunderlugs, where are you located? Wouldn't mind having another set of eyes besides my dad's and mine look her over underneath.

Saturday it is set that I will get the wheel Roadforce balanced at a local shop here in town. Hopefully the beads will be the problem and they will be just fine afterward. How common is a bent rim? I know they're made of steel and do flex a little on turns, but how often do they get bent so bad they cause this?

 

[Thunderlugs]

Thunderlugs, where are you located? Wouldn't mind having another set of eyes besides my dad's and mine look her over underneath.

Saturday it is set that I will get the wheel Roadforce balanced at a local shop here in town. Hopefully the beads will be the problem and they will be just fine afterward. How common is a bent rim? I know they're made of steel and do flex a little on turns, but how often do they get bent so bad they cause this?

PM Me and I will give you my cell.