I have a 2006 Range Rover sport supercharged. The issue I’m having is that shifting from 3-4 gear it will slip quite a bit under throttle and push it back down to third, or it will go up to 5th and go into failsafe. If I am applying little throttle it will stay in 4th but if I apply more throttle it’ll go into 5th and failsafe mode. I replaced the transmission fluid and filled it up to the correct level. I do know the tire profile is a 50 and not 40 like it should be. Any ideas?