I'm in the hunt for a 6.0 and 4l80e. Ones I thought I would get turned out to be...well, too thrashed for the $. Owner seemed to have amnesia too when asked about years, mileage. BTDT enough. I see 99-02's.....and then just found a low mileage '11 in a 3500 van. Looked different (maybe just the cover?). Was anything different in these motors year to year....like some to avoid, or some that need a different, second ECU, injection setups, some that work with a certain head and others that dont, more wiring, etc? Maybe cost in rebuilding? Sounds like a stupid question I know but the vehicles I've messed with the last 20+ yrs had several issues like that. There were 'sweet spot' years that played nice with any accessory or upgrade you wanted to swap, and then those that were year specific or had known design issues you avoided regardless of mileage. Thanks fellas.