The 2021 Ford Super Duty belongs to the 4th generation (2020-2022 powertrain update) (2020-2022), built with 6.2L Boss V8 gas (6R140 6-speed, carryover), 7.3L Godzilla V8 gas (new), or the 3rd-generation 6.7L Power Stroke V8 diesel (new fuel system, pistons, and turbo) - the latter two on the new 10R140 10-speed TorqShift. It takes 5W-30 full synthetic (6.2L and 7.3L Godzilla, WSS-M2C961-A1 on the 7.3L); Motorcraft Super Duty Diesel Motor Oil (6.7L Power Stroke). Oil changes run 7,500-10,000 miles per the oil life monitor (gas engines); 10,000 miles or oil life monitor signal, normal duty (diesel). This is an early year of that generation, which usually means a handful of running changes were still being made.
A 2021 Ford Super Duty is 5 years old in 2026, which at an average 12,000 miles a year puts it around 60,000 miles - the interval that decides its future. At roughly 60,000 miles the bigger fluids come due - transmission, differential, coolant - and this is the window that separates vehicles that reach 200,000 miles from those that do not. Deferring here is what produces expensive failures later. On that mileage estimate it should already have had transmission or CVT fluid, differential fluid and brake fluid at 60,000 miles, and the next milestone is 90,000 miles - a second transmission service, suspension inspection and belts - roughly 2.5 years away at average use.
The fault most worth knowing about on this generation is 6.2L Boss V8 dual-plug ignition system carries the same 16-plug service pattern as 2017-2019. Owners also report First-model-year risk on the new 7.3L Godzilla and 3rd-generation 6.7L Power Stroke, with less multi-year fleet history than the engines they replaced; and EGR cooler fouling/failure carries over as a Power Stroke-family risk. None of these are certainties on any individual vehicle - they are the patterns worth checking for when you buy or when a symptom appears.
Track your 2021 Ford Super Duty service history free with the ServiceSage maintenance tracker, or compare it against other model years on the Ford Super Duty maintenance schedule hub.
| Interval | Service |
|---|---|
| Every 7,500 mi (or IOLM signal; gas V8) | Oil & filter change - grade and capacity per your engine (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Check all fluid levels |
| Every 10,000 mi (or IOLM signal; 6.7L Power Stroke diesel, normal duty) | Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Drain water from the fuel/water separator |
| Every 5,000 mi (severe duty: towing, trailer, extensive idling, off-road, dusty conditions - all engines) | Oil & filter change on the shortened interval - do not stretch past this while towing or plowing regularly, Tire rotation, Inspect brake pads (towing accelerates wear) |
| Every 20,000 mi | Replace cabin air filter, Inspect brake pads & rotors, Inspect front suspension bushings and ball joints - a heavier front end than a half-ton truck |
| Every 22,500 mi (6.7L Power Stroke diesel - fuel filters, normal duty) | Replace both fuel filters (chassis-mounted fuel/water separator and engine-mounted secondary) - 6.7L Power Stroke |
| Every 15,000 mi (6.7L Power Stroke diesel, severe duty or B20 biodiesel blends, or every 6 months whichever comes first) | Replace both fuel filters on the shortened interval - 6.7L Power Stroke |
| Every 30,000 mi | Inspect/replace engine air filter (gas engines), Inspect drive belt condition, Inspect coolant condition and hoses |
| Every 36 months (brake fluid) | Replace brake fluid - Motorcraft DOT 3 LV or DOT 4 LV |
| Every 45,000 mi (6.7L Power Stroke diesel) | Replace the CCV (crankcase ventilation) oil separator - 6.7L Power Stroke, Inspect turbocharger boost hoses and clamps - 6.7L Power Stroke, Coolant flush and refill on the recurring interval for the 6.7L Power Stroke (the first flush lands at a longer mileage under normal duty - see coolant field above; severe-duty trucks are on this interval from the start) |
| Every 60,000 mi (severe duty: towing/trailering/plowing - transmission, transfer case, differentials) | Automatic transmission fluid service - Mercon LV (6R140 six-speed) or Mercon ULV (10R140 ten-speed); the two are not interchangeable, Transfer case fluid change (4x4), Front and rear differential fluid change |
| Every 100,000 mi (6.2L V8 - 16 spark plugs) | Replace all 16 spark plugs (2 per cylinder) - the second plug on the side of each head is easy to miss |
| Every 100,000 mi (7.3L V8 spark plugs) | Replace all 8 spark plugs (1 per cylinder) |
| Every 100,000 mi | Rear differential fluid change (normal duty), Inspect water pump and serpentine belt |
| Every 105,000 mi (6.7L Power Stroke diesel - first coolant service, normal duty) | First coolant flush and refill for the 6.7L Power Stroke - Motorcraft coolant (see coolant field above); much sooner under severe duty (see the 45,000 mi severe-duty row) |
| Every 150,000 mi | Automatic transmission fluid service (normal duty), Transfer case fluid change (normal duty, 4x4), Front differential fluid change (normal duty, 4x4) |
| Every 250,000 mi (6.7L Power Stroke diesel - DPF ash service) | Diesel particulate filter (DPF) ash service for the 6.7L Power Stroke - a dealer regeneration/cleaning procedure, not owner-serviceable; a dash service light indicates when it is due |
The table above is indexed by service interval. This is the same schedule indexed by odometer reading, for when you know your mileage and want the list. If your odometer sits between these figures, work back to the last one you passed and catch up anything skipped.
| Odometer | Service due |
|---|---|
| 30,000 mi (48,000 km) | Oil & filter change - grade and capacity per your engine (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Check all fluid levels, Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Drain water from the fuel/water separator, Inspect/replace engine air filter (gas engines), Inspect drive belt condition, Inspect coolant condition and hoses. |
| 60,000 mi (97,000 km) | Oil & filter change - grade and capacity per your engine (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Check all fluid levels, Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Drain water from the fuel/water separator, Replace cabin air filter, Inspect brake pads & rotors, Inspect front suspension bushings and ball joints - a heavier front end than a half-ton truck, Inspect/replace engine air filter (gas engines), Inspect drive belt condition, Inspect coolant condition and hoses. |
| 90,000 mi (145,000 km) | Oil & filter change - grade and capacity per your engine (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Check all fluid levels, Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Drain water from the fuel/water separator, Replace both fuel filters (chassis-mounted fuel/water separator and engine-mounted secondary) - 6.7L Power Stroke, Inspect/replace engine air filter (gas engines), Inspect drive belt condition, Inspect coolant condition and hoses, Replace the CCV (crankcase ventilation) oil separator - 6.7L Power Stroke, Inspect turbocharger boost hoses and clamps - 6.7L Power Stroke, Coolant flush and refill on the recurring interval for the 6.7L Power Stroke (the first flush lands at a longer mileage under normal duty - see coolant field above; severe-duty trucks are on this interval from the start). |
| 100,000 mi (161,000 km) | Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Drain water from the fuel/water separator, Replace cabin air filter, Inspect brake pads & rotors, Inspect front suspension bushings and ball joints - a heavier front end than a half-ton truck, Replace all 16 spark plugs (2 per cylinder) - the second plug on the side of each head is easy to miss, Replace all 8 spark plugs (1 per cylinder), Rear differential fluid change (normal duty), Inspect water pump and serpentine belt. The every-7,500 mi service runs on its own cycle - the nearest fall at 97,500 and 105,000 miles. |
| 120,000 mi (193,000 km) | Same as the 60,000 mi service. |
| 150,000 mi (241,000 km) | Oil & filter change - grade and capacity per your engine (see oil type/capacity above), Tire rotation, Inspect brakes, belts, hoses, and driveline U-joints, Check all fluid levels, Oil & filter change - Motorcraft diesel-spec oil (see oil type/capacity above), Drain water from the fuel/water separator, Inspect/replace engine air filter (gas engines), Inspect drive belt condition, Inspect coolant condition and hoses, Automatic transmission fluid service (normal duty), Transfer case fluid change (normal duty, 4x4), Front differential fluid change (normal duty, 4x4). |
| 200,000 mi (322,000 km) | Same as the 100,000 mi service. The every-7,500 mi service runs on its own cycle - the nearest fall at 195,000 and 202,500 miles. |
| Fastener | Torque | Size |
|---|---|---|
| Lug nut | 150 ft-lbs (204 Nm) | 13/16in |
| Spark plug | 11 ft-lbs (15 Nm) | 5/8in |
Maintenance keeps these away, but when the dash does light up these are the codes this vehicle throws most often - each with what it means and what the repair actually costs.