Gary asked about the life expectancies of various components.
I will share what I am now using to guide me in replacing parts, and fluids rather than waiting for a failure.
Tires: 6 years or when worn out.
Batteries: 5 years or sooner if a problem occurs.
Brake chambers: 5 years. Note: it is recommended that chambers be replaced every 100,000 miles or one year by Prevost.
Air bags: 10 years. Maybe it is coincidence but two members of this group with 10 year old coaches have experienced air bag leaks, and my previous coach had an air bag leak at ten years.
Air dryer: 2 years.
Engine coolant: 2 years
Engine oil and filters: 5000 miles
Hub seal: As necessary
Air filter: As necessary based on restrictor gauge
Fuel filters: 5000 miles
Transmission oil: 25,000 miles, filters 50,000 miles
Brake pads and lining: As necessary
Air hoses: 10 years or at the first sign of wear from chafing or cracking. (Rubber only, does not include plastic DOT air lines)