Kohler coil
Hey there,
Thanks for reaching out to us! It would be advised to replace both sides so that the older assembly does not cause the new assembly to wear out faster than normal but that it totally up to your discretion.
That being said, your coil assembly appears to use an older, discontinued shoe. The good new is, our 15-177 Coil Balance Shoe will work to replace. While I am confident its the replacement you need, be sure to remove your existing shoe to compare the dimensions.
The Series 152 Coil Balance is the coil spring compatible with this shoe. It is attached using the 33-072 screw. Take a look at the video tutorial below for instructions on how to select the correct coil springs. The 15-143 Coil Bushing, 15-144 Coil Bushing Cap, and 15-145 Coil Support Barrel.