so i had the motor rebuilt, slight cam, crank, oversized pistons...nothing big at all..stock 350 rocket and also had the tranny rebuilt..hooker headers and flowmaster full dual exhaust.

now when i drive the car i have bad shaking around 5o mph and not sure if it the A arms or suspension related, but now while driving down the highway. i have this pulsating vibration coming from the front of the car to the rear and you can feel it coming...

so i think i am going ot buy new upper and lower control arms and replace the u joints, but i am at a loss....

is my drive shaft bent?? is it the exhaust?? please help...the car isnt fun to drive at all...i also need a new steering box or find the adjustment on mine...

 

At those speeds I would first suspect a rear tire is unbalanced. I know it seems like the front, but I had this same experince several years ago. I didn't believe it when I was told it was the rear tire, but lo and behold when it was re-balanced the problem did disappear.

 

well, it seems the wheels do not have weights on it..so i will get them balanced tomorrow and see..how did i miss that..

 

Let me know if that turns out to be the problem. I will be so proud of myself as it is the first problem I helped solved - LOL as opposed to always having a problem to be solved !!!!!!!

 

Does the vibration go away at those speeds in nuetral? Does it get worse if you drive under heavy acceleration? If so I would suspect u-joints.

If not possibbly tire balance or other tire issue.

Steering box adjustment is on top, there is a nut with a slotted adjustment screw in the center. Please note prior to adjusting check all your steering components for wear and play.

 

Tell tale sign of bad U-joints and/or out of balance driveshaft is a "thrumming" at highway speed. Thrummm, pause...thrummm, pause...etc.
Frequency increases with speed, but the sound lessens or disappears when coasting.