Ram Trucks Ram 2500/3500, DJ/D2/DD (USA / CAN)

Additional Notes

• The rear differential fluid capacity for single and dual rear wheel configurations across all engine variants — the 6.4 V8, 6.7 D, and 6.7 D HO — is 3.2 liters. This is the smallest rear differential capacity listed in the specifications and applies to both 4x2 and 4x4 drivetrains.
• Rear differentials fitted with a limited slip unit show a capacity range of 3.2–4.2 liters depending on the specific axle assembly. A range rather than a fixed value reflects the variation between different limited slip differential housings that may be installed across the Ram 2500/3500 lineup.
• The largest rear differential fluid capacity in the specifications is 6 liters, associated with certain limited slip rear differential configurations. A 6-liter fill volume is notably high for a differential and is consistent with heavy-duty axle assemblies designed to handle elevated torque loads.
• Rear dual-wheel differentials without a limited slip unit carry a fixed capacity of 4.2 liters across all engine types and both drivetrain configurations. The same 4.2-liter figure also applies to limited slip differentials paired with dual rear wheels.
• On 4x4 variants of both the 6.4 V8 and 6.7 D engines, the front differential holds 2.1–2.3 liters of fluid. The range accounts for variation between front axle assemblies and is consistent across the standard 6.7 D and the high-output 6.7 D HO (313 kW) in 4x4 configuration.
• Under normal use conditions, the service action for all differential positions across every listed configuration is a fluid level check at 20,000 miles. A check interval rather than a change interval means the fluid is inspected and topped off as needed rather than fully replaced on a fixed schedule.
• Under severe use conditions, the same 20,000-mile interval applies, but the required service action changes from a check to a full fluid change. Severe use typically involves conditions such as towing at or near maximum capacity, frequent off-road operation, or repeated heavy loading, all of which accelerate fluid degradation.
• The 6.4 V8 configurations include a time-based component in the service interval, specifying 20,000 miles or 24 months, whichever comes first. The 6.7 D and 6.7 D HO configurations list only the mileage trigger of 20,000 miles, with no time-based interval stated in the specifications.
• The Ram 2500/3500 6.7 D HO (313 kW) shares identical differential fluid capacities and service intervals with the standard 6.7 D across all axle configurations, despite the higher output rating. The 313 kW designation refers to the high-output version of the Cummins 6.7-liter diesel, and no differential specification differs between the two diesel variants.