2016 Ford F-250 Super Duty — Serpentine Belt Routing, Length & Part Numbers

As an ASE-certified master technician, one of the most common maintenance items I see on the 2016 Ford F-250 Super Duty is a worn serpentine belt. Whether you are hauling heavy equipment with the 6.7L Powerstroke Diesel or running job site routes with the 6.2L V8 Gas engine, a broken belt will leave your rig stranded without power steering, a charging system, or water pump circulation.

Below, you will find the specifications, routing, and part numbers to properly replace the serpentine belt on a 2016 Ford F-250 Super Duty. Note: The specifications below focus primarily on the 6.2L V8 Gas engine with a single alternator. The 6.7L Powerstroke Diesel utilizes a primary and secondary dual-belt system, which requires different routing and part numbers.

Quick answer: 2016 Ford F-250 6.2L V8 Specs

• Belt Length: 102.4 inches (for single alternator configurations)
• Rib Count: 6-rib
• OEM Belt Part Number: Motorcraft JK6-1037-A
• Aftermarket Cross-References: Gates K061024, Dayco 5061025, Continental Elite 4061025
• Auto-Tensioner Part Number: Motorcraft BT-115 (or Gates 39220)
• Idler Pulley Part Number: Motorcraft YS-347 (or Gates 36101)

Belt routing

Pro Tip: Always take a clear photograph of your existing serpentine belt with your smartphone before you loosen the tensioner. This gives you a foolproof visual reference if you get stuck.

For the 2016 F-250 6.2L V8, the grooved side of the belt will ride against the grooved pulleys (crank, A/C, alternator, power steering) while the flat side of the belt will ride against the smooth pulleys (water pump, idler, and tensioner).

Here is the general step-by-step routing path:

1. Start by looping the belt around the bottom of the Crankshaft Pulley.
2. Route it up and around the A/C Compressor.
3. Bring the flat side of the belt over the smooth Idler Pulley.
4. Loop it around the Alternator at the top of the engine.
5. Route it down around the Power Steering Pump.
6. Bring the flat side across the Water Pump pulley.
7. Finally, slip the belt over the Auto-Tensioner as you relieve the spring tension.

How to replace the serpentine belt

Replacing the belt on the 6.2L V8 is straightforward but requires working in a tight engine bay.

1. Locate the Tensioner: Find the spring-loaded automatic belt tensioner on the front of the engine block.
2. Relieve Tension: Insert a standard 3/8" drive breaker bar (or a dedicated serpentine belt tool) into the square slot on the tensioner arm. Rotate the tensioner counter-clockwise (away from the belt) to relieve the spring pressure.
3. Remove the Old Belt: While holding the tensioner open, slip the old belt off the easiest accessible pulley (usually the idler or alternator). Carefully release the tensioner back to its resting state and pull the old belt out of the engine bay.
4. Route the New Belt: Following your photo or the routing diagram above, weave the new belt around all the pulleys except the tensioner or an easy-to-reach idler pulley. Make sure the ribs are seated perfectly into the grooves of every ribbed pulley.
5. Install and Inspect: Apply leverage to the tensioner once more, slip the belt over the final pulley, and slowly release the tensioner so it clamps down on the belt. Double-check every pulley with a flashlight to ensure the belt isn't riding on the lip of a pulley, which will cause it to shred instantly upon startup.

Replacement interval

For a heavy-duty truck like the Ford F-250, preventative maintenance is key. Modern EPDM (ethylene propylene diene monomer) belts do not crack as obviously as older neoprene belts. Instead, the ribs wear down much like the tread on a tire. You should inspect your serpentine belt every 30,000 miles and plan to replace it between 60,000 and 90,000 miles. I highly recommend replacing the auto-tensioner and idler pulley at the same time, as their internal bearings usually fail around the same mileage.

Signs of a failing belt or tensioner

Keep an ear and eye out for these warning signs:

• Squealing or Chirping: A high-pitched squeal on cold startups or when accelerating indicates the belt is slipping. A rhythmic chirping is often a sign of a failing tensioner or idler pulley bearing.
• Visible Wear: Look for missing rib chunks, frayed edges, or heavy glazing (a shiny, hardened appearance on the ribbed side).
• Tensioner Bounce: While the engine is idling, look at the auto-tensioner. It should hold steady. If the tensioner arm is bouncing wildly, the internal spring is weak and the unit needs to be replaced.
• Accessory Issues: Heavy steering at low speeds, random battery warning lights, or poor A/C performance can all be traced back to a slipping serpentine belt.

If you don't have the tools or time to tackle this repair in your driveway, leave it to the professionals. Find a trusted shop on Repairius.