I have a 2000 T4R v6 automatic 4x4. When the weather got cold here, the transmission wouldn't change gears. I would have to manually shift from 1 to 2 to D. It got to the point over the weekend that the transmission fluid started overheating. So yesterday, I replaced the transmission filter and added a quart of Lucas transmission fix. Now my Yoder wont go unless the RPMs are 3500 or higher. Please help, I am a noob and just learning.