My Toyota Highlander will not go into the final gear on the highway. It will stay in "passing gear" and will be around 3,000 rpms. How do I fix this? When engine is cold, it will also "stick gears" where it will hesitate for 5-6 seconds and then jump into the next gear. Toyota has looked at it and no codes have come up, and they test drove and said everything is ok. This is an automatic transmission.