I have a MX5100 HST 4wd that only has about 100 hours on it. The other day my boy used the tractor and put it in High gear and drove around for a while (without permission mind you). Anyway, he said that when he would go up a rise, the tractor would slow down so he pushed the pedal down further and he said it was like a clutch was slipping. He said a couple of times it almost stopped. My question is, did he do any damage to the HST system? I used it yesterday and it seems to be making more noise than it use too. Is there any adjustments or anything I need to check?