for quit a while i have been researching exhausts for my 06 lbz. so far i have found a few i like. they are the mbrp dual 4 inch,the single 5 inch mbrp and the corsa single exit 4 inch.but also dont want a drone in the cab when cruising but i want it to be loud.and should i go cat or no cat. help would be greatly appreciated.:help:

06pimpinduramax,

If you go cat back you won't have any dronne issues at all! On an LLY or LBZ without the cat drone is a rare occurance as the different turbo and such pretty much kills it!
5 inch will be louder than a 4 inch at full throttle but otherwise no big difference when sruising etc. The MBRP offers a much better value as their quality is as good or better than Corsa and they price is a LOT less. Check the poll here:

http://www.dieselplace.com/forum/showthread.php?t=49763

If you have any questions let us know, were MBRP's oldest distributor and can answer any questions you might have.

Mark @ DPPI