Trans slips when it goes to 3rd

[MJB_Hummer]

wanted to let you know...My 2003 was slipping and also shifting way late. AAMCO and my dealer both said what everyone here said. Burned up clutches and need to rebuild transmission. I saw a GM service bullitin, I think somewhere on this forum, anyway that said slipping problems repaired by cleaning valve body. I also noted my fluid looked really good. I took it to a friend of a friend (builds racecars) and he dropped the pan. He also noted fluid looked good and NO clutch material present in the pan. He cleaned the valve body, replaced the filter and fluid and it is shifting fine now. I have only had it back for a few days but so far so good for $500. Just FYI.