Extension Spring
 

I have a 2008 LT1045 Hydrostatic lawn tractor, and I can't keep the belt on, threw the belt 8 times. I was wondering if the extension spring needs to be replaced. Any suggestions?

There is a bunch more factors other than an extension spring adjustment to remedy the belt issue. So, what do I think? I don't know. My crystal ball isn't that good.

Besides the Spring adjustment.... other factors that causes the belt to jump are condition of the belt, correct belt if new, condition of pulleys and the bearings, condition of the deck in regards to alignment of pulleys and structural integrity, and so on. Too many to list.