The Punisher

While driving down the road my '75 seems to shake a lot over even the smallest of bumps. You feel it in the whole car. Car has new front springs,ball joints, control arm bushings, and shocks. Rear has new shocks. Any ideas would be appreciated thanks

bj1k

Have you checked the rag joint for wear ? Sometimes when they are loose it feels like the whole car is shaking. Sounds like you have everything covered unless there is something loose in the rear . Have you checked everything in the rear ?

The Punisher

What should I look for in the rear? And how do I tell if the rag joint is bad?

doorgunner

Rag joint: Have someone slowly turn the steering wheel 4-5" to the left and to the right while you watch the rag joint between the steering box and the steering column where it connects to the rag joint....the rag joint should turn the input shaft in the top of the steering box without having any "slack or play" in either shafts.

Shake: Recheck every part/nut/bolt/bushing/etc. (I forgot to tighten my control arm bushing retaining bolts after I lowered my car for a test drive/one upper shock mount was also loose.

Rescue Rogers

When you say shake, do you mean hop and jump. When I hit a bump mine would bounce then jump side to side and kind of feel squirrelly in the rear. It was my rear alignment. Do your tires wear quickly or unevenly? My alignment was 1.25 " toed in from the back of the tire to the front of the tire and was pointing off past the drivers front wheel. It left running bber shavings all over the rear quarters.

bj1k

Doorgunner pretty much covered the rag joint and as far as the rear it could be trailing arm bushings , bad shocks, a bad wheel bearing in the trailing arm , or something as simple as loose lug nuts on the wheel if you have your car worked on at a garage. Some of the numnuts at the garage just forget. Time to check out everything.

The Punisher

No hopping or jumping. I had a full alignment 2 years ago and tires are wearing fine.

The Punisher

I do my own work so I believe everything is tight that I have touched. I have not worked on any steering components. So I will definitely look at the rag joint. What about the pit man arm bushings? Could that cause shaking ?

terry82

I replaced my idler arm this year .that took out a small shake.you can also rotate the tires just to make sure that you don't have a problem there.

mad pad house

It may be one of the drive shaft universal joints. They can cause a vibration in the car when they start to go.

The Punisher

If it were the driveshaft I think I would feel it all the time. If I am on a nicely paved road I don't notice the shaking

mad pad house

You may be right ,but I would still take a look. Years ago my 71 did much the same thing your car is doing. It drove smooth at times and at other times it would shake like the wheels were about to fall off. The universal on the main shaft at the diff. was just starting to go. Best of luck finding the problem.

LS4 PILOT

My friends totally restored ..1965....not by him.......had something they forgot to replace . It went south a few weeks after he bought it.

That huge snubber bushing at the center of the rear suspension. Was worn.....the body of the car vibrated ....

On a lift .....where you can see and move ..it was obvious. Either they forgot to replace it or it was Chinese defective junk.
Replaced that item and the vibration went away .

The Punisher

Rag joint is tight

DUB

Assuming that the front upper and lower control arm bushings are rubber..and the cupped washers are still tight to them.

How does your car handle in regards to steering when you are on smooth pavement??? I guess it is tight and responsive.

Does the car get out of control in regards to steering when you hit these bumps???

If you have not inspected your trailing arm bushings....I might look at them.

The same goes for the strut rods....and front differential mount bushing.

I would also look at the welds in the front cradle area of the frame and for any metal tears in the steel. Look at where the steering gear box attaches to the frame also.

DUB

The Punisher

ok so I bought rebuilt trailing arms and new strut rods. Shake is still there. I am going to try rotateing wheels to see if that helps. I feel like its more in the body then in the steering, if that makes sense.

theandies

Couple of things. You stated you replaced the front springs. Are the spring ends aligned properly in the spring pockets? How long was your car sitting while you were working on it and how old are your tires? If it sat on old tires for a few months they could have permanent flat spots as old tires won't recover from being on one spot for a long time. Just trying to think "outside" the box.

Jeffs82c3

docmow

i know that you said you tighten them my be same loose and maybe the upper alignment shims fell out mime did

SciVette