Which fluids need to be changed and how often?

Transmission fluid: every 30,000-60,000 miles for most conventional automatics, less often for some sealed units — but 'lifetime fluid' isn't actually lifetime. Coolant: every 30,000-100,000 miles depending on chemistry (green, OAT, HOAT). Old, acidic coolant eats water pumps and radiators.

Brake fluid: every 2-3 years. Brake fluid absorbs moisture over time, which lowers its boiling point and rusts internal ABS components. Power steering, differential, and transfer case fluids: typically every 30,000-60,000 miles, more often for towing or off-road use.

Cabin air filter: usually every 15,000-30,000 miles. It's a small item most drivers never think about, but a clogged cabin filter kills airflow through your HVAC system and lets pollen and dust into the vehicle. We inspect fluids and filters at every service and only recommend replacement when there's a real reason.