How To Tell If Ram Has 3.92 Rear Axle Ratio

How to Tell if Your RAM Has a 3.92 Rear Axle Ratio

Determining your RAM's rear axle ratio is crucial for understanding your truck's performance, fuel efficiency, and towing capabilities. A 3.92 ratio is relatively common, offering a good balance between acceleration and highway cruising. But how do you know for sure if your RAM boasts this specific ratio? Let's explore the various methods to identify your RAM's rear axle ratio.

Methods to Identify Your RAM's Rear Axle Ratio

There are several ways to confirm whether your RAM truck has a 3.92 rear axle ratio. These methods range from quick checks to more involved processes:

1. Check the Door Jamb Sticker

The easiest and quickest method is often overlooked: check your door jamb sticker. This sticker usually contains vital information about your vehicle's specifications, including the axle ratio. Look for a section labeled "Axle Ratio" or something similar. The number listed there will directly tell you the ratio, like "3.92".

Important Note: Not all RAM trucks have this information clearly listed on the door jamb sticker. If it’s missing or unclear, don't worry – there are other options.

2. Consult Your Owner's Manual

Your owner's manual is a treasure trove of information about your RAM. Refer to the specifications section, often found in the first few pages. This section typically details the key aspects of your truck, including the rear axle ratio.

3. Inspect the Differential Tag

This is a slightly more involved method but very reliable. Locate your vehicle's rear differential. It's typically located towards the rear of the vehicle under the truck bed. Once you find it, look for a tag or sticker attached to the differential housing. This tag usually contains information about the gear ratio. Look for numbers like "3.92".

Safety First: Remember to consult your owner's manual or a professional mechanic for detailed instructions and safety precautions before attempting to locate and inspect your differential. Working underneath a vehicle can be dangerous.

4. Mathematical Calculation (Least Reliable Method)

This method involves measuring the driveshaft rotation relative to the wheel rotation. While technically possible, this is the least reliable method and prone to error. It’s generally recommended to use one of the previous methods for accurate results.

Caution: This method requires specialized tools and a deep understanding of automotive mechanics. Incorrect measurements can lead to inaccurate conclusions.

Understanding Your RAM's Axle Ratio

Knowing your RAM's rear axle ratio is beneficial for several reasons:

• Towing Capacity: A 3.92 ratio generally provides sufficient power for towing heavy loads, depending on the engine and other factors.
• Fuel Efficiency: While the 3.92 ratio provides strong acceleration, it might slightly reduce highway fuel efficiency compared to a lower ratio.
• Performance: The 3.92 axle ratio balances acceleration and highway driving, offering a good all-around performance.

Conclusion

Finding your RAM's axle ratio doesn't have to be a complicated process. Start with the simplest methods – checking the door jamb sticker and the owner's manual. If those fail, inspecting the differential tag offers the next most reliable route to confirmation. Remember to prioritize safety when working under your vehicle. Understanding your RAM's axle ratio is key to optimizing your truck's performance and capabilities.