If you get a 8" lift do you have to extend your drive lines?

 

The front driveshaft needs to be lengthened or you can opt for a long spline front driveshaft.
If you have a two piece rear driveshaft you'll need to shim the carrier bearing to eliminate/minimize driveline vibrations. Or you can opt for an aftermarket rear driveshaft for the rear as well.
If you have a one piece rear driveshaft I'm not positive, but I have read of them needed to be lengthed due to insufficient spline engagement causing vibrations.


Hope this helps.

 

Thanks for the Info.