Hi speed vibration 125+mph

[mikeracing]

I have a hi speed vibration. From about 125+ I replaced the driveshaft with a aluminum one. It's not RPM dependant. I have heard the main shaft could be the issue just looking for ideas. I have almost 1,000 track miles and 300 drag passes with slicks with the vibration and just getting tired of it.

[ab_mach1]

Originally Posted by mikeracing

I have a hi speed vibration. From about 125+ I replaced the driveshaft with a aluminum one. It's not RPM dependant. I have heard the main shaft could be the issue just looking for ideas. I have almost 1,000 track miles and 300 drag passes with slicks with the vibration and just getting tired of it.

If you suspect it's the driveshaft, I've read many times over the years that if you loosen and rotate a 1/4 turn and retighten, that you can fix vibration probs with it. I've only swapped out a DS once and didn't have issues, but this has helped others in the past.

[mikeracing]

I tried it with the stock ds a couple years ago no luck. The reason for it older cars the Dr was balanced while on the car so when the shaft is rotated the balance location is thrown off. But that being said still didn't help and the aluminum one didn't help either. Now I'm thinking a main shaft in the transmission the rear end dosent appear to move much. So one day I will have to tear it down.

[mikeracing]

My father suggest ed putting the original yoke in the trans and run it up without the vs attached to see if the vibration is still there

[TKat13]

I've read somewhere in the past that upper bushings have caused this, I have a vibration I am tracking down, pretty much replaced everything and set the pinion angle to offer zero help. My rear bushings are shot upon inspection so that is next. Just thought I'd throw that out there.

[mikeracing]

I replaced the rear bushing top and bottom. In thepast couple years but I appreciate the suggestion. Just food for thought but you want to have a little pinion angle other wise the u joints will wear out sooner than they should.

[ab_mach1]

Originally Posted by TKat13

I've read somewhere in the past that upper bushings have caused this, I have a vibration I am tracking down, pretty much replaced everything and set the pinion angle to offer zero help. My rear bushings are shot upon inspection so that is next. Just thought I'd throw that out there.

And I think Maximum Motorsports recommends the stock type of bushings because they need to be soft to allow some movement. Does that sound right..?