[HUMMERcustoms.com/TAZ]

Handheld programmers will work with only one rig. You remove factory program and install new program which then identifies itself with your vin number.

You have to remove any tuning you have installed because if not when dealer hooks up computer it sees wrong une and over-writes it and you loose the custom tune. Some companies will allow a few times to send back the handheld and will put their tune back in it so you can start over. It is best even though a mess to unload put factory in and reload.

While in dealer they are also always doing upgrades to other computer systems and the factory tune needs to be there for many reasons.

To address sharing a tuning system, you cannot with handhelds. If you go to a laptop tuning program yes you can share a program with a little extra cost if it is still being done. I know my programs for 2003 and 2005 H2's i can tune any vin as I can with any 1999 Silverado's. I think HPTUNERS you can still do this with as that is what I use gotten from them as a sponsorship deal in early 2006. I have one goal left to reach for them and I get a full dealership to tune anything as much a I want. So later mid 2008 if within reasonable distance of Little Rock, AR. I will be able to tune for less than buying programmer but, downside is you do not have the box. I have other ideas but, have to work on a way so that you can pull my tune out and install factory for dealer trips. That will come. I could tune a completely factory bax so you could just unplug and swap them out.

The other option would be Nelson Performance who writes his owns tunes but, you send in your ecu and he ships it back so no better than I could except have 2 boxs.

You can tell tech at dealer and most will make sue not to mess up your tune. They are good guys and understand what you are doing.

Good Luck but, look at SUPERCHIPS programed by HPTUNERS. These guys are very very picky.

TAZ