Premium CAT Pumps Piston and Plunger Pump Oil

Why Use CAT Pump Oil?

You might be wondering why you should exclusively use official brand oil instead of a CAT Pump oil alternative. While it's tempting to use a cheaper, lower quality oil, CAT highly recommends against doing so. CAT’s premium grade oil is formulated to be the best option for your pump and maintains a standard quality that alternatives simply won't adhere to. Consider these benefits of CAT oil, referenced in this lubrication reference sheet from CAT:

• Contains anti-wear additives that protect metal-to-metal drive surfaces, which significantly extends the drive life.
• High oxidative and chemical stability resists deposit formations and provides reliable and consistent performance.
• Premium additives protect pump components from wear, oxidation, rust and corrosion, even in demanding environments like car washes and professional pressure washer units.
  

For technical details and other information about CAT oil, consult this official MSDS from CAT.

How Much Oil Should You Add?

The proper amount of oil to put in your pump depends on the crankcase capacity of the pump, which is typically measured in fluid ounces. You can find this information listed with other specifications for your pump in the data sheets that CAT offers for every line of pumps they manufacturer. These are by far the most trusted source for pump information. You can either visit the CAT brand website and find your pump and associated data sheet, or search for your pump on Kleen-Rite and look under the "Manuals" section on the product page to find the data sheet. If you can’t find the sheet you need, don’t hesitate to call Kleen-Rite’s toll-free line at 1-800-233-3873 to get some help.

Below is a quick list of the crankcase capacity found in the official data sheets for CAT's most popular pump models.

Under 1 bottle needed per oil change:

• 1CX - 2.03 oz
• 4DNX - 8.5 oz
• 4PPX - 8.5 oz
• 280 - 10 oz
• 281 - 10 oz
• 290 - 10 oz
• 291 - 10 oz
• 2SF - 10.1 oz
• 4SPX - 10.1 oz
• 3CP - 12 oz
• 67DX - 13.5 oz
• 230 - 15 oz
• 240 - 15 oz
• 270 - 15 oz
• 5CP - 17 oz
• 310 - 18 oz
• 340 - 18 oz
  
• 350 - 18 oz
• 66DX - 18 oz

Exactly 1 bottle need per oil change:

• 323 - 21 oz
• 331 - 21 oz
• 333 - 21 oz
• 335 - 21 oz
• 390 - 21 oz
• 430 - 21 oz
• 431 - 21 oz
• 435 - 21 oz

Multiple bottles needed per oil change:

• 56 - 25 oz
• 530 - 25 oz
• 550 - 25 oz
• 740 - 25 oz
• 760 - 25 oz
• 7CP - 38 oz
• 621 - 40 oz
• 623 - 40 oz
• 820 - 40 oz
• 821 - 40 oz
• 1010 - 40 oz
• 1011 - 40 oz
• 1050 - 42 oz
• 1530 - 42 oz
• 1531 - 42 oz
• 1540 - 42 oz
• 1541 - 42 oz
• 1730 - 42 oz
• 1731 - 42 oz
• 3531 - 134.4 oz
• 3535 - 134.4 oz
• 3537 - 134.4 oz

Container Sizes Available for CAT ISO 68 Oil

Below are the different size options for buying CAT oil. Buying in larger volume will save you significant money but does require a bigger initial investment and long-term storage.

• 21-ounce bottle
• 2.5-gallon jug
• 30-gallon drum

Quick Savings Breakdown

Here's a simple *cost breakdown to help you understand how much you can save by buying in volume:

• At a cost of $10.58 for 21 ounces, you're paying about $.50 per ounce.
• For the 2.5-gallon jug (320 ounces) at $100.78 and 30-gallon drum (3840 ounces) at $1206.20, you'll pay a little over $.31 per ounce.
• That means if you buy either of the larger containers, you can save about 37% overall versus the smaller bottles.

*Please note that prices are subject to change.

Consider these details when deciding if buying in volume is right for you:

• How many hours your pumps are being used
• Crankcase capacity of your pump
• How much storage space you have available
• Your ability to transport larger containers
• Your immediately available budget

Checking Oil Level

Oil level verification should always be done with your pump on a level, flat surface. For safety and accuracy, your pump should never be turning and pumping water while checking levels. Most CAT pumps have a bubble gauge, with the red dot being the minimum fill level. In some cases, your pump will have an indicator or dipstick to check the oil, with a maximum fill level noted. Take note that overfilling may result in oil spillage from the fill cap. Conversely, if you don’t reach the minimum oil level can cause drive-end failure due to inadequate lubrication.

How to Change the Oil in Your CAT Pump

Prep Area for Safety

• Turn off the machine completely. For full car wash or larger industrial setups, follow appropriate lock-out/tag-out procedures.
• Run the pump for a few minutes beforehand if possible. Warm oil drains much quicker and carries out more contaminants.
• Place an oil drain pan beneath the rear crankcase drain plug. For added convenience and cleanliness, an oil drain kit can be used that has a short hose that precisely directs old oil to the reservoir you're using.

Drain Old Oil

• Find the drain plug at the bottom of rear side of the pump.
• Remove the red top fill cap/breather for ventilation that allows the oil to flow smoothly.
• Loosen the bottom drain plug with a wrench (typically 12mm to 18mm depending on your model) and let the old oil empty completely into your pan.

Pro Tip: Make sure to inspect the oil color and viscosity. If it has a milky color and thinner viscosity, water has bypassed your high-pressure seals and mixed into the oil. If this is the case, you will need to replace your low/high-pressure seals soon.

Clean the Sight Glass

• While not necessary, it's a good idea to clean the sight glass on the component you use to check the oil level. Clearing off residue or film that's collected on it allows you to accurately read levels later. It's generally easier to remove the gauge or indicator, clean it, then reinstall it.

Reinstall the Drain Plug

• Wipe down the drain hole thread, hand-thread the bottom drain plug back in to avoid cross-threading and tighten it securely with your wrench. Do not over-tighten, or you risk cracking the aluminum casing.

Fill with Fresh, New Oil

• Remove cap and place a funnel into the top fill port.
• Slowly pour your fresh CAT ISO 68 oil into the crankcase. Filling gradually allows you to identify any potential leaks without wasting excess oil, while also helping avoid accidental overfilling.
• Stop filling when the oil level reaches the exact center of the red dot on the bubble sight glass or the maximum fill line. Do not overfill; overfilling causes the excess oil to spit out of the red fill cap when operating.
• Screw cap back into the port.

Dispose of Old Oil

• Safely dispose of the old oil, following any legal and environmental regulations.

CAT Pump Oil Change Safety Tips

• Wear gloves and safety glasses before you start, since used pump oil can irritate skin and splash during draining.
• Lock out power and relieve system pressure first. Never service the pump while it is running or still connected to an active trigger gun.
• Let hot components cool if the unit has been in use, although slightly warm oil will drain more easily than cold oil.
• Keep the pump on a level surface so you can drain and refill it accurately, and place absorbent pads or a drain pan under the work area to catch spills.
• Use the correct wrench size and avoid forcing plugs or caps, since damaged threads in the crankcase can lead to leaks and costly repairs.
• After the oil change, dispose of used oil according to local rules, then wipe the pump clean and check for seepage around the drain plug, fill cap, and sight glass.

What Oil Should You Use with Your Pump Model?

CAT makes this very simple. Their ISO 68 oil is used for all of their piston and plunger pump models that have an oil crankcase, with the exception of the R-Series that requires a special ISO 100 oil. The R-Series is a line of very high-volume pumps with oversized inlet and discharge ports, so they are generally not used for car wash or pressure wash applications. As such, we do not carry these pumps or the ISO 100 oil that they use. You can identify R-Series pumps by their model numbers that begin with the prefix "152R."

While the vast majority of CAT plunger and piston models do require oil, there are some exceptions. Most notably, their 1XP Series pumps feature "water-lubricated technology" and do not require oil. Some other specialty models may also not need oil, although this is rare. Always consult the manual or data sheet that came with your pump for specific oil recommendations if you have any questions. CAT centrifugal pumps like the 1K, 2K, 3K, 4K, and 5K Series do not need oil as they feature durable sealed bearings. Lubrication may be required when replacing seals if they're tight, but this should be a NON-OIL OR GREASE lubricant - CAT recommends a non-chlorine dish soap.

Industries That Use CAT Pump Oil

CAT Pump oil is used anywhere CAT high-pressure pumps are part of daily operation, especially in car washes, pressure washing, industrial cleaning, and fluid handling systems. In the car wash industry, operators rely on proper pump lubrication to support dependable performance in self-serve bays, automatic wash equipment, and other wash applications. Professional pressure washer users also use CAT pump oil to protect pumps that run for long periods under demanding conditions. Moreover, contractors, service companies, and facility maintenance teams use it to help reduce wear, limit downtime, and keep equipment service schedules on track. Since many of these operations depend on consistent PSI and flow, using the correct OEM lubricant is a simple step that helps protect pump life and operating reliability.

Frequently Asked Questions

Why is oil shooting out of the cap on my CAT pump?

While there is no pressure forced into the fill cap, it does vent to get rid of any normal pressure that builds up when the temperature of the pump changes. Oil may be shooting from the cap from the following:

• Overfilling of the crankcase
• Frothing caused by using the wrong oil or contaminated oil
• Your pump is running at RPM beyond its rating
  
• The oil cap is loose
• The O-ring on your cap is damaged or worn
• Your pump is mounted on an unlevel surface
• The cap is damaged or warped from excessively high temperatures

Can I use 10W30 in a CAT pump?

No, 10W30 is not the recommended oil for CAT brand pumps. For any other brand of pump, always consult manuals and other official literature for the specific pump you're working with.

Is CAT pump oil compatible with my pressure washer?

If your pressure washer unit uses a CAT brand pump, yes. For example, 66DX, 67DX, 4DNX, and 5CP are some examples of CAT pump models commonly used with pressure washing units. If your pump is manufactured by a different brand, we cannot guarantee compatibility - always consult your manual for information about the oil you should use.