Genuine Toro 106-3987 Recycler Mower Driver 106-3999 108-3766 Spacer Blade Support Kit

Genuine Toro 106-3987 Recycler Mower Driver 106-3999 108-3766 Spacer Blade Support Kit

If your replacing parts this will help tons on vibrations.
This is the adapter that goes from engine to the blade and has pulley for the front wheel drive.
Superseded part numbers 104-8695, 104-8687 Recyclers 2002 & Newer
This adapter has been used since 2002 and it still the current adapter. Used in 201 different models.
If getting vibration from your mower this could be part of the reason.

This part is used in 201 model(s).
Model: 10604 (20in Mulching/Rear Bagging Lawn Mower)
Model: 10606 (20in Mulching/Rear Bagging Lawn Mower)
Model: 10607 (20in Mulching/Rear Bagging Lawn Mower)
Model: 10654 (Gold Series Lawnmower)
Model: 10655 (Gold Series Lawnmower)
Model: 10656 (Gold Series Lawnmower)
Model: 10662 (Insight Lawn Mower)
Model: 10665 (Insight Lawn Mower)
Model: 10665C (Insight Lawn Mower)
Model: 10666 (Insight Lawn Mower)
Model: 10666C (Insight Lawn Mower)
Model: 10670C (Insight Lawn Mower)
Model: 10671 (Insight Lawn Mower)
Model: 10672 (Insight Gold Lawn Mower)
Model: 10673 (Insight Gold Lawn Mower)
Model: 10682 (Insight Lawn Mower)
Model: 10683 (Insight Lawn Mower)
Model: 10684 (Insight Lawn Mower)
Model: 10684C (Insight Lawn Mower)
Model: 10685 (Insight Lawn Mower)
Model: 10686 (Insight Lawn Mower)
Model: 10686C (Insight Lawn Mower)
Model: 10694 (Insight Gold Lawn Mower)
Model: 10695 (Insight Gold Lawn Mower)
Model: 10696 (Insight Gold Lawn Mower)
Model: 10696C (Insight Gold Lawn Mower)