alright so i have a 98 camaro ss ...the person who had it before me put frame connectors and a lowering kit. now i have a bar going from my transmission (t56) to my rear axel. and for the life of me i cant remember what its called..anyways it is adjustable and im wondering if thats not adjusted right cause its my driveshaft thats vibrating (im pretty sure) and i think maybe if the axel is tilted wrong its messing with the ujoint i just replaced both u joints so i know those arent the problems....i havent checked tosee if the driveshaft is balanced correctly but i would assume it is. any ideas on how to adjust it to make it right?

 

The bar from the rear end to the trans is called a torque arm.
When the car is sitting with all four tires on the ground, and the suspension is settled, check the driveshaft to see if you still have some end play between the slip yoke and the tail of the trans. When the rear of the body is lowered (raising the axle), the angle of the driveshaft makes the slip yoke drive further into the transmission. If the slip yoke is bottomed out, you will feel vibrations. Even if it's close now but not bottomed out, hitting bumps or dips will make the yoke slide forward a little and could be enough to bottom out.
In case you're wondering how much clearance you should have, with the tires on the ground, the slip yoke should be pulled out of the tail (from fully bottomed out) at least 3/4"-1".
And here's how to check your pinion angle: http://www.carcraft.com/howto/91758/index.html

 

wow thanks a lot! you helped me more in a few minutes than everyone in my town has in the last few months! haha another thing thats goin on is that the car is lowered a few inches so im wondering if the axle sits back a little more than its supposed to because of those bars that connect the axle to the body...i also dont know what theyre called but theyre from the same kit as the frame connectors