Hi i have a TYM T451 and ive tried checking the hydraulic fluid on it and i cant seem to get a consistent reading on it. Ive parked it in the same spot twice and different readings each time? Ive had it all the from empty to full. Its parked in the most level spot i can find as well. It had a dipstick if that helps. Any idea on which reading i should use or what would be causing this?