So its time to trade in the 2005 GMC Envoy XL. Looking to get a 2005-2006 Chevy Tahoe 4x4. Does anyone know what to look for as far as common problems and such? The one we looked at today has173K on it but just one owner and it is very clean with leather seats. The trans and engine are very smooth. Noticed a slight rough idle when the ac is on. Rpms were steady, cruise works as expected. Has auto everything. Tows 7700 lbs which is the reason for us to move. Any info is appreciated. Thanks.