2019 Ford F-150: Transmission & Axle Gear Ratios

Transmission Gear Ratios

The 2019 Ford F-150 was available with two automatic transmissions: a 6-speed and a 10-speed. The transmission used depends on the engine choice.

10-Speed SelectShift Automatic (10R80)

This transmission is the more common of the two, paired with the 2.7L EcoBoost, 3.5L EcoBoost, 5.0L V8, and 3.0L Power Stroke diesel engines.

6-Speed Automatic (6R80)

This transmission was only available with the base 3.3L V6 engine.

Available Axle Ratios

Ford offered a wide range of axle ratios for the 2019 F-150, allowing buyers to tailor the truck's performance to their needs, whether for fuel efficiency, towing, or a balance of both.

Note: Electronic Locking (EL) differentials were available for most ratios, often indicated by a different axle code (e.g., L9 for a 3.55 EL, L3 for a 3.31 EL, L6 for a 3.73 EL).

How to Identify Your Axle Ratio

Knowing your truck's specific axle ratio is crucial for ordering parts or understanding its towing capabilities. Here are the primary ways to identify it:

1. Door Jamb Sticker: The most reliable method is to check the Safety Compliance Certification Label located on the driver's side door jamb. Look for the "AXLE" code listed on the sticker and match it to the codes in the table above.

2. Axle Tag: Ford trucks have a metal tag bolted to the differential cover. This tag contains information about the gearing and differential type. The ratio is typically stamped in a clear format like "3 55" for a 3.55 ratio. If the ratio has an "L" in it (e.g., "3L55"), it indicates a limited-slip differential.

3. VIN Decoder: While less direct, some online VIN decoders can provide details about your vehicle's original factory configuration, including the axle ratio.

Towing vs. MPG Impact

The axle ratio has a direct and significant impact on both fuel economy and towing performance. The principle is straightforward:

• Numerically Lower Ratios (e.g., 3.15, 3.31): These are often called "taller" gears. The engine needs to turn fewer revolutions to rotate the wheels, resulting in better fuel economy at highway speeds. The trade-off is reduced leverage for getting a heavy load moving, meaning lower towing and payload capacities.

• Numerically Higher Ratios (e.g., 3.73, 4.10): Known as "shorter" gears, these ratios multiply the engine's torque more effectively. This makes it much easier to tow heavy trailers and haul significant weight. The downside is that the engine must run at a higher RPM on the highway, which increases fuel consumption.

For the 2019 F-150, a 3.55 ratio is often considered the best all-around compromise, offering good unloaded performance and fuel economy with the capability for moderate towing. Those who prioritize maximum towing capacity should look for trucks equipped with the 3.73 ratio, often found in conjunction with the Max Trailer Tow or Heavy-Duty Payload packages.

Common Issues

While the F-150 driveline is generally robust, some issues can arise over time, particularly in trucks that are used for heavy towing or have high mileage.

• Ring & Pinion Whine: A whining noise from the rear differential that changes pitch with vehicle speed can indicate worn ring and pinion gears. This is often caused by improper gear setup, lubrication failure, or high stress from towing.
• Carrier Bearing Failure: Worn or failed carrier bearings can produce a humming or rumbling noise from the differential area. The noise may change when turning.
• Limited-Slip Clutch Wear: In axles equipped with a limited-slip differential (like Ford's "Traction-Lok"), the internal clutches can wear out over time. This will result in the differential behaving more like an "open" differential, with one wheel spinning freely when traction is lost.

Early diagnosis and repair of these issues are key to preventing more catastrophic and expensive failures.

Find a driveline shop on Repairius.