2018 Ford F-150 Transmission & Axle Gear Ratios

Transmission gear ratios

The 2018 Ford F-150 offered two primary transmission options: the 6-speed automatic and the 10-speed automatic. The 10-speed became standard on most trims and engines, significantly improving both performance and fuel efficiency.

6-Speed Automatic Transmission (6R80)

10-Speed Automatic Transmission (10R80)

Available axle ratios

Ford offered a wide range of axle ratios for the 2018 F-150, allowing owners to tailor their truck for specific needs, from maximizing fuel economy to heavy-duty towing.

How to identify your axle ratio

For the 2018 Ford F-150, the easiest way to determine your truck's axle ratio is by checking the door jamb sticker on the driver's side. Look for the "Axle" code under the "TR" (Transmission) section. This two-digit code corresponds to a specific axle ratio and type (open, limited-slip, or electronic locking).

Alternatively, some F-150s may have an axle tag attached to one of the differential cover bolts. This metal tag will often have the ratio stamped directly on it. If you're still unsure, a Ford dealership can decode your VIN to provide precise specifications.

Towing vs MPG impact

Axle ratios play a significant role in determining a vehicle's performance characteristics. A numerically lower axle ratio (e.g., 3.15) means the engine has to turn fewer revolutions to rotate the wheels once. This results in lower RPMs at highway speeds, leading to better fuel economy. However, it also means less torque multiplication, which reduces towing capacity and acceleration.

A numerically higher axle ratio (e.g., 4.10) provides more torque multiplication to the wheels. This allows the truck to pull heavier loads and accelerate more quickly, especially from a standstill. The trade-off is higher engine RPMs at highway speeds, which generally decreases fuel efficiency.

For the 2018 F-150, if your primary use involves long highway commutes or light hauling, a 3.15 or 3.31 ratio would be ideal. If you frequently tow heavy trailers or engage in off-road activities, a 3.55, 3.73, or even a 4.10 ratio would be more beneficial, providing the necessary pulling power.

Common issues

While Ford F-150 axles are generally robust, some common issues can arise:

• Ring and Pinion Whine: This often manifests as a howling or whining noise that changes with vehicle speed and throttle input. It can be caused by improper gear meshing, worn bearings, or excessive backlash. If left unaddressed, it can lead to premature gear failure.
• Carrier Bearing Wear: The carrier bearings support the differential carrier within the axle housing. Worn carrier bearings can cause a rumbling or vibrating noise, especially when accelerating or turning. This can also lead to excessive play in the drivetrain and potential damage to other components.
• Limited-Slip Clutch Wear: For F-150s equipped with a limited-slip differential, the clutch packs can wear out over time, leading to a loss of traction in low-traction situations. Symptoms may include a "chattering" or "clunking" noise from the rear end when turning tightly, especially at low speeds.

Regular differential fluid changes and inspections can help mitigate these issues and extend the life of your F-150's axle components.

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