Trucks been acting up lately. Surprised the trans held out so long without problems given the use. Generally hangs in second while cold (trans below 115F) and shifts to third when it feels like it. Shift seems unrelated to RPM or throttle position. Sometimes shifts so late when cold I think I could hit the governor. When warm generally shifts ok; however, it will still periodically delay shift even when temps are above 130F. Fluid level ok, front band correctly adjusted, linkages correct and in spec. Anyone out there with an idea? Basically stock trans with 150k miles. If it likely internal lip seal or other PITA can anyone recommend an experienced shop in Sacramento, CA area.