Iron Treads's best moveset in Pokémon GO is Splash and Struggle, with 11.32 damage per second, and it can deal 403.0 damage before Iron Treads faints. This is true when battling in neutral weather.
All Iron Treads movesets ranked
Here is a complete list of Iron Treads movesets in Pokémon GO, ranked by their DPS and TDO. You can change the weather and the opposing Pokémon.