Hillman GT

Manual transmission fluid capacity & service interval

Hillman GT manual transmission fluid capacity ranges from 2,5 to 3,06 liters. Service intervals occur every 8000 km or 6 months. The data covers 1 configuration.

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

TypeSpecifications
GT (1968-1974)
  • Use: Normal
  • Capacity 2,5 liter
  • Capacity 3,06 liter (+ overdrive)
  • Check 8000 km/ 6 months
  • Code: 4/1

Additional Notes

  • The Hillman GT manual transmission holds 2.5 liters of fluid in standard configuration, a figure consistent with a service fill volume for a compact manual gearbox of that era.
  • When the overdrive unit is fitted, the total fluid capacity rises to 3.06 liters, reflecting the additional volume required to lubricate the overdrive mechanism as part of the same shared fluid circuit.
  • The 0.56-liter difference between the standard and overdrive capacities represents the fluid demand of the overdrive assembly alone, which is a meaningful distinction when servicing or topping up rather than performing a full drain and refill.
  • Under normal use conditions, the specified check interval is 8,000 km or 6 months, whichever comes first, applying equally across the 1968-1974 model range regardless of whether the overdrive is fitted.
  • The dual-format interval, combining a distance figure with a time limit, means that low-mileage operation still triggers a fluid check at the 6-month mark, preventing extended periods without inspection in vehicles driven infrequently.

Other Systems