2022 Ram 2500 Transmission & Axle Gear Ratios

Transmission gear ratios

The 2022 Ram 2500 comes with two transmission options depending on the engine choice: the 68RFE 6-speed automatic for the 6.4L HEMI V8, and the Aisin AS69RC 6-speed automatic for the 6.7L Cummins Turbo Diesel.

6.4L HEMI V8 – 68RFE 6-Speed Automatic

6.7L Cummins Turbo Diesel – Aisin AS69RC 6-Speed Automatic

Available axle ratios

The 2022 Ram 2500 offers a range of axle ratios to suit different needs, from improved fuel economy to maximum towing capability. These ratios vary based on engine, trim level, and specific packages.

How to identify your axle ratio

For most Ram trucks, identifying your axle ratio is a straightforward process. The most common method is to check the RPO (Regular Production Option) sticker. This sticker is typically found on the inside of the glove box door or on the driver's side door jamb. Look for a three-digit code that starts with "DM" followed by a letter (e.g., DMH for 4.10, DMQ for 3.73). If you cannot locate the sticker or the code, a Ram dealership can perform a VIN decode to provide you with the original build sheet information for your truck, which will include the axle ratio.

Another method, though less common on newer trucks, is to check for an axle tag. This metal tag, if present, is usually bolted to one of the differential cover bolts. It will have numbers stamped on it that indicate the gear ratio.

Towing vs MPG impact

The choice of axle ratio significantly impacts both your truck's towing performance and its fuel economy. Here’s a simple breakdown:

• Numerically lower ratios (e.g., 3.73): These ratios mean the engine turns fewer times for every rotation of the wheels. This results in lower RPMs at cruising speeds, which generally leads to better fuel economy. However, with less mechanical advantage, the engine has to work harder when towing heavy loads, potentially reducing towing capacity or making the truck feel less responsive under load.

• Numerically higher ratios (e.g., 4.10): These ratios mean the engine turns more times for every rotation of the wheels. This provides a greater mechanical advantage, allowing the truck to pull heavier loads with less strain on the engine. This makes higher ratios ideal for frequent or heavy towing. The trade-off is higher engine RPMs at cruising speeds, which typically results in decreased fuel economy.

For the 2022 Ram 2500, the 3.73 axle ratio offers a good balance for drivers who occasionally tow moderate loads and want decent fuel efficiency for daily driving. The 4.10 axle ratio is better suited for those who frequently tow heavy trailers or operate in demanding conditions where maximum pulling power is essential.

Common issues

While Ram 2500 axles are generally robust, some common issues can arise:

• Ring & Pinion Whine: A high-pitched whine that increases with vehicle speed can indicate wear or improper setup of the ring and pinion gears. This often becomes noticeable during deceleration or at specific speed ranges.

• Carrier Bearing Wear: As an axle accumulates miles, the carrier bearings that support the differential assembly can wear out. Symptoms include a low-pitched howl or rumble that changes with vehicle speed and can be exacerbated during cornering.

• Limited-Slip Clutch Wear: If your Ram 2500 is equipped with a limited-slip differential, the clutch packs can wear over time. This can lead to a loss of traction in slippery conditions, chattering or clunking noises during tight turns, or uneven power delivery to the wheels.

Regular differential fluid changes and inspections can help mitigate these issues and extend the life of your axle components.

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