Ford 39 Axle Code

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Article: Ford 39 Axle Code


When it comes to understanding a vehicle’s specifications, the axle code plays a crucial role. In this article, we will dive into the details of the Ford 39 axle code, its significance, and what it means for Ford vehicle owners.

What is an Axle Code?

An axle code is a combination of letters and numbers that represents the characteristics of the vehicle’s axles. It provides valuable information about the axle ratio, differential type, and other crucial details related to the vehicle’s drivetrain.

The Ford 39 Axle Code

The Ford 39 axle code is commonly found in Ford vehicles and represents a specific set of axle characteristics. This code indicates that the vehicle is equipped with a 3.55 axle ratio and an open differential.

3.55 Axle Ratio

The axle ratio refers to the number of rotations the driveshaft makes in relation to the rear axle’s rotation. In the case of the Ford 39 axle code, the ratio is 3.55, which means that for every 3.55 rotations of the driveshaft, the rear axle completes one full rotation.

Open Differential

An open differential is the most common type of differential found in vehicles. It allows the wheels on the same axle to rotate at different speeds, especially during turns. This design provides ease of handling and is suitable for everyday driving conditions.

Advantages of the Ford 39 Axle Code

The Ford 39 axle code offers several advantages for Ford vehicle owners:

1. Fuel Efficiency

The 3.55 axle ratio allows for optimal balance between power and fuel efficiency. It provides sufficient torque for acceleration while ensuring the engine operates at an optimal RPM range, resulting in improved fuel economy.

2. Towing Capability

The Ford 39 axle code is well-suited for towing applications. The 3.55 axle ratio provides the necessary torque to tow moderate loads without putting excessive strain on the engine.

3. Everyday Driving

With an open differential, the Ford 39 axle code offers smooth handling and maneuverability during everyday driving. It allows for easy turning and ensures both rear wheels receive power from the engine, providing adequate traction.


The Ford 39 axle code with a 3.55 axle ratio and an open differential is a popular choice among Ford vehicle owners. It strikes a balance between fuel efficiency, towing capability, and everyday drivability. Understanding the axle code can help you make informed decisions when it comes to maintenance, modifications, or purchasing a Ford vehicle.