What Type Of Oil Should I Use on My Simpson Pressure Washer?

Simpson pressure washers are renowned for their robustness and efficiency. As with all machinery, using the right oil is paramount to ensuring the longevity and optimal performance of the pressure washer.

This guide will help you determine the best oil for your Simpson pressure washer.

The Quick Answer…

For a Simpson pressure washer, Simpson recommends using their own brand of oil. Ideally you will need to use 15W40 pump oil for the pressure washer’s pump.

You can buy it via Amazon here.

Simpson Pump Lubricant: Exclusive mix of 15W40.

Efficiency: Specially designed non-foaming formula to enhance pump efficiency and shield essential pump parts.

Compatibility: Suitable for a majority of pressure washer pumps.

Lubricant Replacement Guideline: Simpson advises replacing the pump oil following the first 50 hours, and subsequently every 100 hours or every quarter.

Packaging Volume: Simpson Elite Crankcase Lubricant comes in a 1 U.S. Pint (16 ounces) container.

Understanding the Manufacturer’s Recommendation:

For a brand as reputable as Simpson, always start by considering the manufacturer’s oil recommendations. Doing so ensures compatibility and maintains warranty conditions.

The Ideal Choice: Simpson’s Proprietary Blend

  • Premium Pump Oil: Simpson has its proprietary blend of oil labeled as 15W40. This blend is tailored to provide the necessary lubrication and protection the washer pump requires.
  • Performance: This oil is a non-foaming formula, purposefully designed to optimize pump performance and shield crucial pump parts from wear and tear.


While Simpson’s proprietary oil blend is optimized for its equipment, it’s vital to note that this 15W40 blend is compatible with most pressure washer pumps. Therefore, even if you have different machinery, this oil could potentially be a suitable choice.

Oil Change Intervals for Simpson Pressure Washers

Routine maintenance is as crucial as the oil type. Simpson recommends changing the pump oil after the initial 50 hours of use.

Following this, it’s advisable to change the oil every 100 hours or every three months, whichever comes first. Adhering to this schedule ensures the pump’s long life and consistent performance.

Other Engine Oil Alternatives for Simpson Pressure Washers

While Simpson’s proprietary oil is the go-to choice, in some scenarios, you might need an alternative. If opting for another brand or type, ensure that it is compatible with pressure washer pumps, non-foaming, and has similar viscosity to 15W40.

Premium brands that meet these requirements could potentially be used, but always cross-check with Simpson’s guidelines.

Disposal of Used Oil

After changing the oil, make sure you dispose of the used oil responsibly. Many localities have special facilities for collecting and recycling used engine oil. Environmentally-friendly disposal ensures sustainability and reduces pollution.


While there are multiple oil options in the market, for Simpson pressure washers, their proprietary 15W40 blend remains the top choice. Not only does it ensure maximum pump performance, but it also offers peace of mind, knowing that you’re using a product recommended by the manufacturer itself.

Remember, regular maintenance combined with the right oil ensures your Simpson pressure washer remains a reliable workhorse for years to come.

Leave a Comment