STM Engine Break-In Guidelines

If you've recently purchased a new STM Engine, please review these suggested guidelines for engine oil, precautions and break-in procedures.

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Break-In Instructions & Guidelines:

  • Use AMSOIL Break-In Oil (SAE 30) during the entire break-in process.
  • Recommended oil after break-in:
    • AMSOIL Dominator 15w50
  • Use OEM oil filters only.
  • Make sure to monitor and check coolant temperatures and oil pressures.
  • Vary RPMs during break-in. City driving is recommended.
  • If your previous motor failed, DO NOT reuse any components that oil ran through from that motor including the oil filter housing, oil cooler, oil pump, etc. Anything that is reused such as the cylinder head, valve cover, etc. must be thoroughly cleaned out and checked. One piece of debris can ruin your entire motor.
  • If you had your valve cover powder-coated, you MUST CHECK for powder residue. This will absolutely destroy your bearings!


Startup Checklist and Procedure:

  1. Fill the oil filter completely with oil prior to installing.
  2. We recommend running the oil at 1/2" to 1" over the fill mark (all the time.)
  3. Make sure proper tune is loaded to safely run the car without being too rich or lean.
  4. Be sure to prime engine before starting. We suggest using the Canton Racing Pre-Luber (24-160).
  5. Once oiling system has been primed and confirmed to have pressure, start the engine and continue to monitor oil pressure. If oil pressure is low, oiling system might not be fully primed or there is a problem elsewhere. Oil pressure will vary by vehicle and where you are taking your reading from. If you have questions, please contact us.
  6. Heat cycle the motor and check for any leaking oil or coolant.
  7. Drive the car at varying RPMs (no full boost or WOT) for about 20 miles.
  8. Drain oil, remove oil filter and cut apart to check for any metal debris.
  9. If everything looks good, fill with recommended synthetic oil above.
  10. Break-in is complete! It is a good practice to check your oil filter and monitor oil pressure throughout the life of the engine.


Oil Change Packages: