2024 Ram 3500: Transmission & Axle Gear Ratios

The 2024 Ram 3500 is a heavy-duty powerhouse built for monumental towing, payload capabilities, and long-haul endurance. A critical component of its legendary performance lies in its driveline—specifically the transmission and axle gear ratios. Whether you are pulling a heavy fifth-wheel camper across the country or hauling equipment to a job site, having the right gearing dictates your truck's mechanical advantage, fuel economy, and pulling strength.

Below is a comprehensive guide to the transmission options and axle ratios available in the 2024 Ram 3500, along with how these choices affect your driving experience.

Transmission gear ratios

For the 2024 model year, the Ram 3500 offers three different transmissions, heavily dependent on your engine choice. The 6.4L HEMI V8 is mated to a ZF-sourced 8-speed automatic, while the 6.7L Cummins Turbo Diesel engines use heavy-duty 6-speed automatics (the 68RFE for the Standard Output and the Aisin AS69RC for the High Output).

8HP75-LCV 8-Speed Automatic (6.4L HEMI V8)

68RFE 6-Speed Automatic (6.7L Cummins Standard Output)

Aisin AS69RC 6-Speed Automatic (6.7L Cummins High Output)

Available axle ratios

Unlike half-ton trucks that offer a wide array of axle ratios, heavy-duty trucks like the Ram 3500 keep things focused strictly on high-capacity hauling and towing. Ram limits the 3500 pickup choices primarily to two robust ratios for the American Axle & Manufacturing (AAM) rear ends.

How to identify your axle ratio

Knowing your truck's exact axle ratio is vital if you are buying a used 2024 Ram 3500 or if you plan on maxing out your towing capacity. Here is how you can verify your gear ratio:

• Door-jamb RPO/Equipment Sticker: Unlike GM trucks that use a traditional RPO code sticker in the glovebox, Ram typically places an equipment identification sticker on the driver's side door jamb or provides a build sheet. Look for codes like DME (3.73) or DMF (4.10).
• Axle Tag: Crawl under the rear of your truck and look at the differential cover. Ram trucks feature a metal tag bolted to one of the differential cover bolts. It will have numbers stamped on it, such as "3.73" or "4.10", often alongside the fluid requirement.
• VIN Decoder: The easiest and cleanest way to check is to run your Vehicle Identification Number (VIN) through the Mopar owner's portal or a dedicated Ram VIN decoder. The original window sticker (Monroney label) can also be pulled up via the VIN, displaying the exact axle ratio optioned from the factory.

Towing vs MPG impact

When it comes to axle ratios, you are always playing a game of give-and-take between low-end torque and highway fuel economy.

Numerically lower ratios (3.73): Often referred to as "taller" gears, a 3.73 ratio means the driveshaft turns 3.73 times for every full rotation of the tires. This ratio is standard for the Cummins diesels because the engine produces so much low-end torque (up to 1,075 lb-ft on the HO) that it doesn't need aggressive gearing to get moving. A 3.73 ratio yields lower cruising RPMs on the highway, which results in noticeably better fuel economy.

Numerically higher ratios (4.10): Known as "shorter" or "lower" gears, a 4.10 ratio requires the driveshaft to spin 4.10 times per tire rotation. This provides greater mechanical leverage, making it much easier for the truck to get heavy loads moving from a dead stop. It also reduces strain on the transmission when pulling massive fifth-wheel RVs. The trade-off is higher engine RPMs at highway speeds, which will decrease your overall fuel economy.

Common issues

The 2024 Ram 3500 utilizes massive AAM 11.5-inch or 12.0-inch rear axles, which are incredibly durable. However, even heavy-duty components can experience wear and tear, especially when subjected to extreme towing stresses:

• Ring & pinion whine: If you hear a high-pitched whining noise under acceleration or deceleration, it can indicate improper backlash or wear on the ring and pinion gears. This sometimes happens if the differential fluid is not changed after the initial break-in period or if the truck was used to tow far beyond its limits.
• Carrier bearing wear: Dually models and long-wheelbase trucks have a two-piece driveshaft with a center support carrier bearing. Shuddering on takeoff, particularly when loaded, can point to a failing carrier bearing.
• Limited-slip clutch wear: If your Ram 3500 is equipped with the Anti-Spin rear differential, the friction plates inside the limited-slip unit can wear out over time. Symptoms include a popping or chattering sensation when making tight turns, or the inability to lock both wheels on slippery surfaces.

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