I have a 20 year MTD lawn tractor that has been very reliable. Last summer I noticed while cutting my lawn, as I climb a fairly steep grade that the tractor looses power almost to a crawl. No other problems on level terrain. The RPM's remain constant, the mower just slows down and almost stops. It is as if a transmission is slipping. Where do start looking to solve this problem?

Check tension on the belts. It sounds as if you may not be familiar and maybe bringing it in to have them replaced is a good idea. Do it now and beat the spring rush.

Regards,
Don

I'm sorry I wasn't more clear. The blades are turning just fine, the problem is that the mowers drive seems to be slipping as I climb the incline.

There would be a drive belt for the transmission(transaxle) and it is kept under tension by a idler pulley and tension spring.

Thanks,
Don