Every M12 tool I have still works, even after 10+ years of auto repair. The batteries are far superior to any aftermarket brands, I have tried almost all of them . Now my tools are used for lawn and garden repair. They will last till I am gone.
I put Amsoil 20w-50 in my Deere hydro at 120 hours. It now has 305 hours
and pulls up my hills like new. Had to remove transaxle and dump old fluid out. Really not that hard to do. Use full synthetic….