I just joined this site since it look like it has a lot of good info. I retired a couple of years ago and am spending more time in my shop playing with toys (and doing odd jobs to make money for more toys) so spend a bit of time on various sites digging for info. I haven't done too much on my GMC other than an Edge Juice w/Attitude, Air Intake, and a bypass oil filter (didn't buy a kit. Just put together my own using a Baldwin bypass base and filter, etc.). I use the GMC (Dually Crewcab) to pull my 5th Wheel RV trailer so am mostly concerned about longevity and efficiency. I also have a 1984 Chevy pickup that's an Army surplus CUCV (they rate it as a 1 1/4 ton) with a 6.2L that I've put a Banks Sidewinder turbo and Gear Vendors overdrive on. I carry an old SIXPAC 8 foot camper on it for beating around in the mountains finding good fishing holes and doing a bit of gold panning and metal detecting. The next project is the old Chevy COE that's on the trailer in my profile picture. I just got a 1984 Chevy chassis motorhome that I'm going to use the chassis from and plan to put a Duramax/Allison in it, drop the COE cab onto it (will be a tilt cab) and a stepside bed with hydraulic dump on it. Should be able to haul some beauty bark for the flower beds with that. Thanks to all of you guys that post the great info!