shifting

Hello! I have a 2007 Chevy Tahoe LS with a strange issue.. sometimes the automatic transmission shifts late. When it does, it won't shift until sometimes 4k RPM, and normally it late shifts near 3500. Some days it will work as if nothing is wrong, and other days it'll do it all day long...

Hey guys, Need some quick help. Have 02 Tahoe 5.3 w/ 147k miles on it. Have had it serviced regularly. Has run great, no issues what so ever. So , I'm pretty alarmed that 4 days ago,(after driving home from work) the trans shifted REALLY hard when I started off from the traffic light. It only...