Husky RZ5424 zero turn,

Hello all!
Newbie here. My RZ5424’s parking brake seems to have quit working. I set brake, start mower, and it immediately lunges backwards, kind of in a left hand backward turn. Almost seems like right drive tire is locked but left is not… was fine yesterday…. Any ideas? This model has a separate parking break lever….

You appear to have two problems.

One the brake arm at the transaxle is likely worn out. Can't tell just at a glace, must remove and look at it.

Second the hydro gear transaxle neutral setting is not set right. Even with worn out brake arm(s) it should still not move forward or backward with the arms [lap bars] in neutral.

Thanks Star tech, will look at brake arm and neutral setting.