at 100mph or so my stock drive shaft has the common shudder problem. Will balancing cure it? A local heavy truck shop can do do it for around $70

 

For that price I'd spend the extra 30$ and pick up an ls1 driveshaft, no vibration and pickup about 5rwhp.

 

It may and it may not. I would just get the ls1 driveshaft as stated above...

 

Ditto.

 

If you want to keep the strength of your steel DS (stronger than an LS1 aluminum), have it balanced. If you have recently had it off, you might try unbolting it and rephasing it 180° and see how it feels.

 

No, it's never been off the car and i've owned it since 98'. Thanx for your replies, i think i'm gonna go with balancing the old one unless i can find a aluminum shaft around here for around $100 which i really doubt.