hi all i still have a problem on my 4.6 thor engined gearbox it seems at times to be slipping but does know what gear it wants to be in and goes up and down the box at any speed but pulls away fine and know codes until i use kick down i then get gearbox error but this dosent give me a code but it does drive better once i have used kick down i have done one oil and filter change but maybe needs another all ideas welcome