The Ford F-350 Super Duty is built for strength, whether it’s towing massive loads, powering through job sites, or hauling cross-country. But with great power comes great responsibility. Owning a heavy-duty truck like the F-350 means you must stick to a strict maintenance routine to keep it reliable and efficient for the long haul.

Unlike half-ton pickups, the F-350 works under more intense conditions: higher payloads, greater towing stress, and heavier engine/transmission workloads. That’s why maintenance is essential.

Related guide:

F-350 Super Duty Reliability & Common Problems

Ford F-350 Super Duty Light Bulb Size Guide

What Does “Severe Duty” Mean?

Many F-350 drivers fall under the “severe duty” category without realizing it. This includes frequent towing or hauling, driving on dusty or gravel roads, extreme weather (hot or freezing), extensive idling, or taking many short trips. These conditions accelerate wear and tear, requiring more frequent maintenance compared to normal use.

Why the Owner’s Manual Still Matters

Every F-350 model year and engine configuration has its own unique maintenance schedule, so while this guide offers professional and general advice, nothing replaces the information in your official Ford Owner’s Manual. You can download it online at the Ford Owner’s Manual site.

Understanding Maintenance Intervals

Mileage vs. Time

Most service intervals are based on mileage (e.g., every 5,000 or 10,000 miles). However, if you don’t hit those mileage numbers in a timely manner, time-based intervals (like every 6 or 12 months) still apply—especially for fluid degradation or component aging.

“Normal” vs. “Severe” Schedules

Ford provides two service schedules: one for “normal” driving and one for “severe duty.” Given how F-350s are typically used, most owners should follow the severe duty intervals to avoid premature wear and performance loss.

Key Maintenance Categories

The major maintenance categories include fluid services (oil, coolant, transmission, brake), filter replacements (air, fuel, cabin), system inspections (lighting, suspension, steering, brakes), and wear item replacements (belts, plugs, tires).

F-350 Super Duty Maintenance Schedule: Mileage Breakdown

Every 5,000 Miles / 6 Months – The Severe Service Baseline

This is your core interval under severe service:

Change the engine oil and filter without fail—this is the single most critical maintenance task, especially for diesel engines under heavy load. Always use oil and filters that meet Ford’s specs.

Rotate tires to ensure even wear on such a heavy-duty truck.

Have a multi-point inspection done: check fluid levels and condition, inspect belts and hoses, test the battery, examine brakes, look over the suspension and steering, inspect the underbody, and verify light and wiper function.

Diesel models also need a fuel filter change to prevent clogging in high-pressure fuel systems.

Every 10,000 Miles

Repeat all the 5,000-mile tasks, plus:

Check the automatic transmission fluid level and condition—look for signs of discoloration or burnt smell.

For 4x4 models, inspect the transfer case and front axle fluid levels.

Every 15,000 Miles / 12 Months

Replace the cabin air filter to maintain HVAC efficiency and cabin air quality.

Repeat all applicable tasks from earlier intervals.

Every 30,000 Miles

Check or replace the engine air filter—this directly affects engine performance and fuel economy.

Perform a full automatic transmission fluid and filter change (especially important under severe use).

Change transfer case and axle fluids if you drive a 4WD model.

Repeat all prior services to keep your truck in optimal shape.

Every 60,000 Miles

Flush and replace brake fluid—it absorbs moisture and degrades over time.

Replace power steering fluid.

Flush and replace engine coolant. Diesel trucks typically use long-life OAT coolants (like Ford Yellow); always check the type in your manual.

If you have a gasoline engine, replace the spark plugs and fuel filter at this interval.

Every 100,000 Miles & Beyond

Repeat the full 30,000- and 60,000-mile services.

Inspect and possibly replace the serpentine belt and tensioner—preventative maintenance can avoid a roadside failure.

Check the idler pulley for wear or noise.

Do a comprehensive inspection of suspension and steering components: look for loose ball joints, worn tie rods, damaged bushings, or leaking shocks.

If you own a diesel F-350, consider having the EGR valve cleaned, fuel injectors tested, and the turbocharger inspected by a diesel specialist.

Seasonal & Usage-Specific Maintenance Tips

Winter Prep

Test your battery’s charge and health, check coolant freeze protection levels, switch to winter-rated washer fluid, and monitor tire pressure more often. If you’re in very cold climates, consider using a block heater.

Good lighting is also critical during winter, when daylight hours are shorter and visibility often suffers. If your F-350 still runs on halogen bulbs, consider upgrading to LED headlight bulbs and fog light bulbs from SEALIGHT. They offer superior brightness and cut through snow, fog, and darkness far more effectively.

Summer Prep

Make sure your coolant system is ready for the heat. Test the A/C system, and again, keep a close eye on tire pressure, which fluctuates with high temperatures.

Heavy Towing or Hauling

Stick strictly to severe duty intervals. These loads create additional strain on your engine, brakes, and transmission. Check fluids more often and consider upgrades like a larger transmission cooler.

Off-Road Driving

Wash the undercarriage frequently, inspect the suspension for damage or looseness, and change differential and transfer case fluids more often. Air filters may need replacing sooner due to dust.

For safer night-time or low-visibility trail driving, upgrade your headlights to the brightest LEDs for clearer and farther-reaching illumination.

Final Thoughts: Protect Your Truck, Drive with Confidence

The Ford F-350 Super Duty is a beast of a truck—and with proper care, it can serve you well past 200,000 miles. But that kind of longevity only comes with consistent and smart maintenance.

Remember: the most important rule is to consult your owner's manual and follow the severe service schedule if your driving habits demand it.

For optimal visibility and safety, don’t forget to upgrade your headlights and auxiliary lighting. SEALIGHT offers premium LED bulbs that are perfect for heavy-duty trucks like the F-350. Whether you drive through dusty trails, dark highways, or winter storms, SEALIGHT LED bulbs offer superior brightness and durability.

Shop SEALIGHT LED bulbs today and take your visibility to the next level. And if this guide helped you, leave a comment—we’d love to hear how you keep your F-350 running strong.