Riley RM

Differential fluid capacity & service interval

Riley RM differential fluid has a capacity range of 1,4 to 2,3 liters. Service intervals include 800, 3200, 8000, and 10000 hours for changes, and 1600 kilometers or 1600 hours for checks. The data covers 14 configurations.

The configuration chart below lists fill volumes and service intervals for each engine and trim variant.

TypeSpecifications
  • RME (1953-1955)
  • Rear
  • Use: Normal
  • Capacity 1,56 liter
  • Change 3200 hours
  • RME (1953-1955)
  • Rear
  • Use: Initial service
  • Capacity 1,56 liter
  • Change 800 hours
  • RMF (1952-1953)
  • Rear
  • Use: Normal
  • Capacity 2,3 liter
  • Check 1600 km
  • Change 8000 hours
  • RMF (1952-1953)
  • Rear
  • Use: Initial service
  • Capacity 2,3 liter
  • Change 800 hours
  • RMF (1952-1953)
  • Rear
  • Use: Normal
  • Capacity 1,4 liter
  • Check 1600 hours
  • Change 10000 hours
  • RMF (1952-1953)
  • Rear
  • Use: Initial service
  • Capacity 1,4 liter
  • Change 800 hours
  • RMD (1949-1951)
  • Rear
  • Use: Normal
  • Capacity 2,3 liter
  • Check 1600 km
  • Change 8000 hours
  • RMD (1949-1951)
  • Rear
  • Use: Initial service
  • Capacity 2,3 liter
  • Change 800 hours
  • RMC (1948-1951)
  • Rear
  • Use: Normal
  • Capacity 2,3 liter
  • Check 1600 km
  • Change 8000 hours
  • RMC (1948-1951)
  • Rear
  • Use: Initial service
  • Capacity 2,3 liter
  • Change 800 hours
  • RMB (1946-1948)
  • Rear
  • Use: Normal
  • Capacity 2,3 liter
  • Check 1600 km
  • Change 8000 hours
  • RMB (1946-1948)
  • Rear
  • Use: Initial service
  • Capacity 2,3 liter
  • Change 800 hours
  • RMA (1945-1952)
  • Rear
  • Use: Normal
  • Capacity 1,56 liter
  • Change 3200 hours
  • RMA (1945-1952)
  • Rear
  • Use: Initial service
  • Capacity 1,56 liter
  • Change 800 hours

Additional Notes

  • The Riley RM range spans six variants across 1945-1955, and rear differential fluid capacities fall into three distinct groups: 1.56 liters, 1.4 liters, and 2.3 liters, reflecting differences in axle hardware across the lineup.
  • The RMA (1945-1952) and RME (1953-1955) share a rear differential capacity of 1.56 liters, with normal-use fluid changes scheduled at 3,200-hour intervals.
  • The RMB (1946-1948), RMC (1948-1951), RMD (1949-1951), and one configuration of the RMF (1952-1953) all carry a 2.3-liter rear differential capacity, a notably larger fill than the 1.56-liter variants.
  • The 2.3-liter differential configurations on the RMB, RMC, RMD, and RMF specify a fluid level check at 1,600 km intervals under normal use, a separate and more frequent task than the fluid change interval of 8,000 hours.
  • The RMF (1952-1953) is the only variant in the range with two distinct rear differential specifications: one at 2.3 liters with an 8,000-hour normal change interval, and a second at 1.4 liters with a 10,000-hour normal change interval, indicating two different axle assemblies were fitted to this model.
  • The 1.4-liter RMF differential configuration carries the longest normal-use change interval in the range at 10,000 hours, and also includes a fluid level check specified at 1,600-hour intervals.
  • Across all six variants and every capacity group, the initial service fluid change is uniformly set at 800 hours. This early change interval is standard practice for new or rebuilt differentials, allowing metal particles generated during the break-in period to be flushed from the housing.
  • Hour-based service intervals, rather than distance-based ones, were a common specification method for vehicles of this era, particularly where operating conditions varied widely and odometer readings were considered a less reliable measure of mechanical wear than elapsed running time.

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