[Justaman]

I was wondering if you guys might be able to help me with a problem I am having. I had some 4.56 gears installed now I am getting a bad vibration at 60+ MHP. It goes away when I pull the front drive shaft. I have had the drive shaft balanced and the vibration is still there. I am replacing my trans mount this weekend to see if that will help any other idea's on what I should do?

 

[Wharfrat]

During constant speed, accel, decell, or all the time?

 

[JayH]

u joints and centering kit in double cardan OK?

 

[Justaman]

It does it all the time and gets worse the faster I go. I had the CV rebuilt in the drive line and the shop said that all of the U-Joints looked good. This is on a selc-a-trac with a 4.0L engine.

 

[JayH]

tires balanced?

 

[Wharfrat]

Angles correct?

 

[Justaman]

I have had all my tires balanced. The angles should be good I only have a 3.5in lift. Plus I don't know how to check the angles.

 

[JayH]

if it goes away when the front driveshaft is removed, and the front driveshaft has been re-balanced and the u joints, CV, and double cardan are all in good shape and the tires are balanced, hmmmm

It's possible you got a bad balance, or you're experiencing a grind from the diff instead of a vibration. If the latter, then take it back to the shop and have them fix their work. If the former, find another driveline shop.

Jay

 

[Dylan]

you say you have 4.56. with those new gears everything spins a lot faster at 60 mph then they did befor. this means that your vibes could have been there befor but not as noticable sence you would need to go say 90 mph to notice it. most driveline angles are set to run up to a certen speed. most likley its a driveling angle thats off. you are gona need to set them at a closer tolerence with the new gears.

 

[MCracco]

Worst case, a high pinion D30 swap will fix it.

 

[Justaman]

Ok how do I check my angles and adjust them. I am guessing I just move my lower controll arms making them longer or shorter right. So how many deg. angle should they be?