Purpose-built for engine break-in during dyno or test bed runs (up to 4 hours), Millers Oils Running-In Oil is a high-quality, mineral-based formulation designed to protect freshly built engines during the critical early stages of operation.

Formulated using premium solvent-refined mineral oils, this running in oil is fortified with low volatility components and carefully selected additives. The result is a balanced oil that provides:

• Exceptional protection for new engine components
• Optimised bedding-in process
• Controlled wear to allow proper surface mating
• Suitable for both road and test bed use

Ideal for high performance and motorsport engine builds, this oil ensures your engine beds in correctly without glazing bores or compromising long-term performance.

Sold in a 5L tub. The following measurements are required for MINI engines:

• Gen 1 - W10, W11 - 5L
• Gen 2 - N12, N14, N16 and N18 - 4.2L
• Gen 3 - B48 - 5.3L, B38 - 4.3L 

Lohen follow the following running in process to 

1. Fill the engine to the recommended dipstick level using a quality running in oil like Millers Running-In Oil.
2. Run the engine under peak torque loads for approx. 200 miles under controlled conditions on a rolling road.
3. Monitor the following indicators to confirm the running-in phase is complete:
   • Compression levels meet the correct specification
   • Noticeable improvement in performance and throttle response
   • Enhanced fuel efficiency
   • Reduced oil consumption