Look at where the forward/reverse lever (3) hooks to the rod (29) underneath.
That rod goes to the transaxle
Make sure it's pulling and pushing the link on the trans the same distance.
Look for anything that looks to be an adjustment for that rod also.
The parts breakdown of your machine doesn't show it.
Troy Bilt 13WM77KS011 Pony (2015) Transmission Exploded View parts lookup by model. Complete exploded views of all the major manufacturers. It is EASY and FREE
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