If you have an automatic LT 1000 I would think the problem is in the transmission, I also have an automatic LT 1000 with an 18 hp Motor. I pulled the transmission out not to long ago to find a shaved spline on the neutral something or other. If you look up the exploded view of the transaxle it is part nine. I think it is called the nuetral sleeve, about 12 bucks but labor intensive. Hope this helps
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