Mower has significant loss of torque. Even slightest uphill is a struggle for it to negotiate. I looked at the maual but it says take it to a Snapper dealer. The last time I did that they didn't fix it. I have replaced the rubber drive plate and that helped a little but it is anemic. I am getting tired of having to help push it along on an incline. Any way to adjust the horizontal drive plate on the engine so it presses harder agains the rubber drive plate on the axle?