2017 Ram 3500 Transmission & Axle Gear Ratios

Transmission gear ratios

The 2017 Ram 3500 offered two primary transmission options: the 68RFE 6-speed automatic and the Aisin AS69RC 6-speed automatic. The Aisin transmission was standard with the High Output Cummins Turbo Diesel engine.

68RFE 6-Speed Automatic Transmission Ratios

Aisin AS69RC 6-Speed Automatic Transmission Ratios

Available axle ratios

The 2017 Ram 3500 offered a range of axle ratios, allowing buyers to tailor their truck for specific needs, whether it's heavy-duty towing or maximizing fuel efficiency.

Note: Availability may vary slightly based on specific trim levels and packages.

How to identify your axle ratio

For Ram trucks (and some older Mopar vehicles), the axle ratio information is typically found on a label located on the differential itself, or on a build sheet or decal under the hood or in the glove box. Owners of 2017 Ram 3500 trucks will often find this information on a sticker located in the glove compartment or on the driver's side door jamb, which lists various RPO (Regular Production Option) codes. Look for a three-digit code starting with "DM" (DME, DMH, DMK) to identify your axle ratio. For a definitive answer, you can also contact a Ram dealership with your VIN, and they can provide a detailed build sheet.

Towing vs MPG impact

Numerically Lower Ratio = Better MPG, Higher Tow Capacity (within reason)

• Lower Numerical Ratios (e.g., 3.42): These ratios mean the engine turns fewer revolutions per minute (RPM) at a given road speed. This generally translates to better fuel economy, especially during highway driving, as the engine isn't working as hard. However, it results in less torque multiplication at the wheels, meaning reduced towing capability and slower acceleration, especially with heavy loads.

• Higher Numerical Ratios (e.g., 4.10): These ratios cause the engine to turn more RPMs at a given road speed. This provides greater torque multiplication, resulting in significantly increased towing capacity, stronger acceleration, and better performance under heavy loads or when tackling steep grades. The trade-off is often reduced fuel economy, particularly at higher speeds, as the engine is working harder.

Balanced Ratio (e.g., 3.73): This ratio strikes a balance between fuel efficiency and towing capability, making it a popular choice for those who need to tow occasionally but also want reasonable daily driving fuel economy.

When choosing an axle ratio, consider your primary use for the truck. If you frequently tow heavy trailers or large campers, a higher numerical ratio like 4.10 will be beneficial. If your truck is mainly a daily driver with occasional light towing, a 3.42 or 3.73 might be more appropriate.

Common issues

While the Ram 3500 is known for its robust drivetrain, certain components related to the axle and differential can experience wear or issues over time, particularly with heavy use or inadequate maintenance.

• Ring and Pinion Whine: A common sign of wear, improper gear mesh, or low differential fluid is a howling or whining noise that changes with vehicle speed. This often indicates issues with the ring and pinion gears, which are at the heart of the differential.

• Carrier Bearing Wear: The carrier bearings support the differential carrier within the axle housing. Worn carrier bearings can lead to noise (a growling or rumbling sound), vibration, and eventually significant damage if not addressed.

• Limited-Slip Clutch Wear (if equipped): Trucks equipped with a limited-slip differential rely on clutches to distribute power to both wheels. Over time, these clutches can wear out, leading to a loss of the limited-slip function, noticeable as one wheel spinning freely in low-traction situations where both should be driving. This can also manifest as chattering or clunking sounds during turns.

Regular differential fluid changes with the correct fluid type and friction modifiers (for limited-slip differentials) are crucial for prolonging the life of these components.

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