I HAVE A 300 SDL THAT RUNS GOOD BUT SOMETIMES IT SHIFTS INTO 4TH GEAR RIGHT AFTER IT SHIFTS INTO 3RD GEAR. OTHER TIMES IT SHIFTS LIKE THE OTHER GEARS AFTER THE ENGINE REVS OUT A LITTLE. I HAVE NOTED THIS MOSTLY USING LIGHT TO MEDIUM ACCELERATION. UNDER HARD ACCELERATION IT SHIFTS FINE. IT HAS 223K ON IT AND IS IN EXCELLENT COND. ANYONE EVER HEARD OF THIS??