I recently swapped my 5.3 engine out for a 6.0 in my 04 tahoe. We also installed a small gm performance hot cam with a nelson tunned pcm. The truck runs great, but has a less then desirable idle. The problem we have is when you are in drive but at a stop the truck bucks and jerks slighty making you feel like it wants to move when the brakes are on. It is very anoying to deal with. Does anyone have any ideas at what to look for? Thanks guys.