AW32 vs AW46: Which Hydraulic Oil is Right for Your System?

Selecting the right hydraulic oil for your machinery is a critical decision. The choice between AW32 and AW46 can significantly impact performance and longevity.

So the question is AW32 vs AW46, which is better?

The main difference between AW32 and AW46 hydraulic fluid is their weight. AW32 is a 10-weight fluid, while AW46 is a 20-weight fluid. 

AW32 is a good all-season fluid that is best suited for use in cooler outside temperatures. AW46 is best suited for older equipment at moderate temperatures. They also differ in viscosity, applications, and performance. 

To dive more into details about these oils, keep reading this article. It will clear all your confusion to make the right decision. 

AW32 vs AW46: Quick Overview

Let’s check a quick difference between the two hydraulic oils before we move on to a detailed discussion:

Differences AW32 AW46
Weight 10-weight fluid 20-weight fluid.
Viscosity Thinner, less viscous Thicker and more viscous than AW32.
Temperature Range All temperatures especially for cold weather Better suited for warmer weather.
Applications Pump of a snowplow etc Hydraulic systems for dump trucks, excavators, and other off-road machinery.
Performance Good for anti-wear but not sufficient for higher loads Great performance higher pressure and temperature.
Rust resistance Almost the same level of rust protection Rust-free for a long time.

Now that you have an overview, let’s move on to a more detailed discussion:

What is AW32 Hydraulic Oil?

AW32 hydraulic oil is a zinc-based, non-detergent oil with an ISO viscosity grade of 32.

It contains a zinc anti-wear additive that reduces wear and protects hydraulic systems and equipment. AW32 also contains rust and foam inhibitors.

AW32 is made for use with industrial and mobile hydraulic systems and has an operating temperature range of 413°F to -11°F. It’s designed for high-pressure hydraulic systems with gear, piston, or vane pumps.

What is AW46 Hydraulic Oil?

AW46 hydraulic oil is a premium-quality, general-purpose anti-wear hydraulic fluid. It contains a zinc/phosphorous additive to reduce wear and provide protection against rust, corrosion, and oxidation.

AW46 hydraulic fluids have an International Standards Viscosity Grade (ISO VG) of 46. AW46 hydraulic oil is used to operate the hydraulic systems in off-road equipment such as dump trucks, excavators, and backhoes.

What is the Difference Between AW32 vs AW46 Hydraulic Oil

Picking the right hydraulic oil for your specific hydraulic system is crucial. It’s because the wrong choice of oil can easily lead to your machinery showing fault codes and warning lights.

Factor 1: Weight

AW46 is heavier in weight than AW32, meaning it won’t easily flow as AW32. One of the main differences between AW32 and AW46 is their weight. AW32 is a 10-weight fluid whereas AW46 is a 20-weight fluid.

Hydraulic fluids with higher weight can’t flow easily because of their stickiness or thickness. So in terms of weight, AW32 is the better choice, but the hydraulic system needs and temperature should be considered in this decision as well.

AW32 vs AW46

Source: Amazon

Factor 2: Viscosity

AW46 is more viscous than AW32. AW32’s lower viscosity comes from its lower weight. It can easily flow in the system making it suitable for various equipment. These characteristics make them perfect for a faster cold start of the system. It also reduces the exhaust emission as well.

However, the higher viscosity of AW46 allows it to be great fluid for heavier loads. It makes lubrication easier and protects the system components.

So, both of these hydraulic fluids serve their purpose. It depends solely on the hydraulic system to pick the fluid with the right viscosity. 

Factor 3: Temperature Range

AW32 is better suited for colder temperatures whereas AW46 is the best pick for higher temperatures.

With lower weight and viscosity, AW32 fits perfectly for hydraulic systems that mostly work in cold temperatures. You can easily use this fluid in the fall, winter, and early spring months with better fluidity.

And with higher viscosity, AW46 performs the best in higher temperatures. With better lubrication, AW46 works seamlessly with older equipment in moderate to higher temperatures.

Factor 4: Performance

AW32 and AW46 are both great for antiwear and keeping your equipment running smoothly.

These Petroleum-based fluids along with the anti-wear additives in them keep your machineries running smoothly without any damage. So, whichever fluid you pick your machinery will be in good running capacity.

AW46  is better for highly demanding industrial operations. It performs best under high pressure and temperature.

However, AW32 is not necessarily known for its performance with higher loads. It is better suited for lighter loads and in colder temperatures.

Factor 5: Applications

Both AW32 and AW46 work great indoors under moderate temperatures.

For outdoor operations such as industrial machinery, and heavy-duty applications like construction equipment AW46 is the better pick. Moreover, the dump truck’s hydraulic system and off-road machinery work better with the AW46 fluid.

Machinery with lighter duty like agricultural equipment and hydraulic systems of mobile AW32 fluid oil is mostly preferred. Along with those, AW32 is great for snow plow pumps.

Factor 6: Rust Resistance

AW46 is slightly better at rust resistance than AW32. The additive compositions of AW32 and AW46 hydraulic oils help to defend against oxidation and rust.

 Technically, AW-32 and AW-46 both have the same amount of oxidizing and other additives in their formulation. However, because AW-46 is thicker and has a higher oil content, it helps to keep hydraulic systems safe from rusting over time.

So with its increased viscosity and oil content, AW-46 might offer marginally superior rust resistance.

Factor 7: Price

The prices of AW32 and AW46 from the same brand are the same. 

Both AW 32 and AW 46 from TRUEGARD are priced at $598 for a 55-gallon drum. This price may vary between different brands but 

AW32 vs AW46: Which One to Get for Your Equipment

Source: Amazon

AW32 vs AW46: Which One to Get for Your Equipment?

AW32 is generally better suited for colder temperatures, while AW46 is best suited for older equipment at moderate temperatures.

So pick AW32 for your system if the temperature of where you live tends to get low during winter. And if the temperature remains moderate and doesn’t fall too much during winter, AW46 is the better pick.


Is AW 46 Hydraulic Oil Available in Zinc-free Formulation?

Yes, AW 46 hydraulic oil is available in zinc-free formulation. Performance Plus® Zinc Free AW 46 Fluid and Bosse Lubricants™ AWZF Hydraulic Oils are engineered using a zinc-free formula. These premium base oils will provide you with excellent protection in industrial applications and automobiles.

Can You Mix AW32 and AW46 Hydraulic Fluid?

Yes, it is possible to mix AW 32 with AW 46 but only if they have the same additives. Otherwise, they will cause serious damage to the hydraulic system. You need to consider their viscosity and whether they are from the same brand. This is necessary for compatibility.

What Hydraulic Oils Are Compatible with AW 46?

Several hydraulic oils are compatible with AW46. Mobil DTE 25, Shell Tellus 46, and Chevron Rykon Oil AW 46 are all compatible with AW-46 hydraulic fluid. You can also mix Lucas Oil’s AW-46 with AW-32 if a higher viscosity is needed. 

End Words

That’s the end of our discussion on AW32 vs AW46. It ultimately comes down to your hydraulic system and its specific requirements while choosing the hydraulic oil. 

If you are unsure about the requirements make sure to check in with a professional to clear out the doubt. Until next time!


Leave a Comment

Your email address will not be published. Required fields are marked *