Vibration

[BlackBetty_67]

I have a vibration in 4th gear when i hit 50 mph. I have a new transmission, new tires and rims, new drive shaft (balanced). I wanna say the vibration has decreased when i replaced these items but not fully. I was wondering if it may be the differential angle? What should it be?

[Admin]

year please or is it a 67?


OK we need to trouble shoot this.

what happens in 3rd at the same MPH?

When did this start, meaning what was done to the car around the time the vibration started to appear?

Is your car the same height as other cars, meaning is the differential angle any different from other cars?

I am leaning more toward the front suspension, was the car aligned?  Do you have the printout of before, during and after readings? If might be possible there's too much negative caster, wobble in the toe readings, or a weight may have come off the rotor. Are there brake rotors in the front and drum brakes in the rear?  Or all drums?

How was the old tire wear for each tire?, Even, worn on one side, wavy, or anything else that would look uneven?
 

[BlackBetty_67]

67 COUPE.

The vibration in minimal in 3rd gear. It started when i snatched a second. Guess i learned my lesson. Can't tell if the rear end turned or not.

The car is the same height as other cars so it should be the same angle.

The front suspension is a interesting point. i never got the car aligned. Haven't had it that long and never meet the previous owner. I think a alignment would be a good idea.

I have disc on front and drums in the rear.

Wasn't much tire wear at all. i changed tires and rims after the vibration started. still no change.

I've changed, tires, rims, drive shaft, u joints. seems like there should be a machine that could tell me exactly where it is. I appreciate your input in this matter.

[Admin]

The vibration is minimal in 3rd gear...

Hmm...

Thats important. Would you say the vibrations changes from really bad to a slight vibration?  Also, if you put the trans in neutral while going 50MPH, does the vibration go away? 
If it does go away, I'd start looking real hard at the drive train.  The transmission would be first.

Sometimes you know especially with the front end, if you have a few parts worn out, you can't really pin down front end problems, but those few worn parts would all come into play as each little problem equals a big problem. We'd tell the customer that we can't pinpoint the problem but advise them to replace all the slightly worn parts, one at a time or all together.

[Admin]

67 COUPE.

 seems like there should be a machine that could tell me exactly where it is. I appreciate your input in this matter.

There is a tool made for this. Sensors are placed at different parts of the car, then drive it and return to read the data collected.  I'd think the dealership or specialty shops would have this.  I just don't recall if this is for sounds or vibrations.