Toro LX426 lawn tractor- Jerks like a gear broken in forward, Runs great in reverse

[robertlsu007]

This is the model with a variable speed built into the transaxle/transmission. The foot lever connects directly to the transaxle. Herky jerky like gears stripped in forward, goes perfectly in reverse. Jacked up the back end and forward and reverse work fine. Any rider producing drag and it feels like a stripped gear but reverse works fine. ANY HELP APPRECIATED. Thanks.

PS first time in a forum so manners and speed may be lacking.