Ford F53 Owner's Manual page 147

Every 105000 miles
(168000 km)
Every 150000 miles
(240000 km)
*
Initial replacement at six years or 105000 miles (168000 kilometers), then every three
years or 45000 miles (72000 kilometers).
**
If not replaced, inspect every 15000 miles (24000 kilometers).
Motorhome (TY3) Canada/United States of America, enUSA, Edition date: 201712, Second Printing
Scheduled Maintenance
Other maintenance items
Change engine coolant.
Replace rear axle fluid.
Inspect accessory drive belt(s).
Replace accessory drive belt(s) if not replaced within the
last 100000 miles (160000 km).
Replace front wheel bearings and seals if non-sealed
bearings are used.
144
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