Im in the process of buying a 3" body lift...I have custom dual exhaust straight out the back of the truck...my question is , once the lift is on, will my exhaust be at the same height as it is now(3" lower than the body)? Thanks!

 

Yep.

 

Would that be the same case if you were to do a Add-A-Leaf-Spring?

 

your exhaust is fastened to the chassis only. so when you put this body lift on, the exhaust is going to remain in the same spot it is now. you may want to have an exhaust shop raise your exhaust system after you put the lift on. they should only have to raise the hangers