2020 Ford F-350 Super Duty Serpentine Belt Routing & Replacement Guide

The serpentine belt on your 2020 Ford F-350 Super Duty is a critical component that drives the engine’s accessories, including the alternator, water pump, power steering pump, and air conditioning compressor. Whether you are driving the 6.2L Gas V8, the 7.3L Godzilla V8, or the 6.7L Power Stroke Diesel, keeping your drive belt in top condition is essential for the reliability of your heavy-duty truck.

Below is a comprehensive guide focusing on the standard single-alternator 6.2L V8 gas engine setup (specs may vary slightly for the 6.7L diesel or dual-alternator packages, so always verify with your VIN before purchasing).

Quick Answer

Here are the essential specifications and part numbers for the 2020 Ford F-350 Super Duty (6.2L V8 Gas, Single Alternator):

• Belt Length: 103.3 inches
• Rib Count: 6-rib
• OEM Belt Part Number: Motorcraft JK6-1033
• Aftermarket Cross-References: Gates K061033, Dayco 5061035, Continental Elite 4061033
• Auto-Tensioner Part Number: Motorcraft BT-115 (Gates 38392)
• Idler Pulley Part Number: Motorcraft YS-385 (Gates 36101)

Note: If your F-350 is equipped with the 6.7L Power Stroke Diesel or a dual-alternator package, you will have a different belt configuration (often utilizing two separate belts).

Belt Routing

Because engine bays can be complex and we cannot render an image here, it is highly recommended that you photograph the existing belt before removal. Use your phone to take a few clear pictures of how the belt weaves around the pulleys.

For the standard 6.2L V8, the belt routing follows this general text-based path:

1. Start by looping the belt down around the bottom of the Crankshaft Pulley.
2. Route it up and over the A/C Compressor.
3. Bring the belt under the smooth Idler Pulley.
4. Pull it up and over the Alternator at the top of the engine.
5. Route it down and around the Power Steering Pump.
6. Wrap the smooth back-side of the belt over the Water Pump.
7. Finally, slip the belt under the Auto-Tensioner pulley (you will need to relieve the tension to slide it fully into place).

How to Replace the Serpentine Belt

Replacing the serpentine belt on a 2020 Ford F-350 is a manageable DIY job if you have the right tools and a clear understanding of the routing.

Tools Needed:

• Serpentine belt tool or a long 3/8" drive breaker bar
• Safety glasses and gloves

Step-by-Step Instructions:

1. Locate the Tensioner: Find the automatic belt tensioner on the front of the engine block.
2. Release the Tension: Insert your 3/8" breaker bar or serpentine belt tool into the square receptacle on the tensioner arm. Rotate the tensioner counter-clockwise (or away from the belt) to relieve the tension.
3. Remove the Old Belt: While holding the tensioner open, slip the belt off the easiest accessible pulley (usually the idler or alternator). Carefully release the tensioner and remove the old belt from the engine bay.
4. Route the New Belt: Following your reference photos or the routing path described above, weave the new belt around all the pulleys except for the final one (leave the idler or tensioner pulley for last). Ensure the ribbed side of the belt sits perfectly into the grooved pulleys, and the smooth side rests against the smooth pulleys.
5. Install the Belt: Crank the tensioner open again, slip the belt over the final pulley, and slowly release the tensioner.
6. Verify Seating: Double-check every pulley with a flashlight to ensure the belt is perfectly aligned in the grooves before starting the engine.

Replacement Interval

For a heavy-duty truck like the F-350, preventative maintenance is key. Ford generally recommends inspecting the serpentine belt every 30,000 miles. Most modern EPDM belts can last anywhere from 60,000 to 90,000 miles. However, if you frequently tow heavy loads, idle extensively, or operate in extreme temperatures, you may need to replace the belt and tensioner closer to the 60,000-mile mark. It is heavily advised to replace the tensioner and idler pulleys at the same time as the belt, as the bearings in these components wear out at a similar rate.

Signs of a Failing Belt or Tensioner

Do not wait for your belt to snap on the highway. Look out for these common warning signs:

• Squealing or Chirping Noises: A high-pitched squeal upon startup or acceleration often points to a stretched belt or a weak tensioner spring.
• Visible Wear: Look for deep cracks, missing ribs, fraying edges, or a shiny, glazed appearance on the belt surface.
• Accessory Malfunctions: If your power steering feels suddenly heavy, your A/C stops blowing cold, or the battery warning light illuminates on your dash, the belt may be slipping or broken.
• Tensioner Movement: With the engine running, watch the tensioner. If it is bouncing excessively or rattling, the internal spring or dampener has failed, and the assembly needs immediate replacement.

If you aren't comfortable tackling this heavy-duty maintenance task yourself, don't worry. Find a trusted shop on Repairius.