My navigator doesn't seem to be moving as swiftly as it used to. This will it's 3rd summer coming up. I added an extra link of hose and the range seemed to get a little better, but it sure does crawl around at a snails pace. I've taken it apart and looked at the internals and everything seems to be working ok. The pads look ok too - no excessive wear. Just wondering if there is any other maintenance issues I could check to improve perfromance.