Best John Deere Hydrostatic Transmission Fluid Substitutes

by Synthetic Oil | Last Updated: June 21, 2022

Throughout the years, John Deere has become a force in manufacturing that is known to produce high-quality products, including their hydrostatic transmission and hydraulic oil known as Hy-Gard. Unfortunately, John Deere hydraulic oil can be a little expensive, so you may be searching for a substitute that fits the bill.

Below, you will be introduced to several oils that can be used as a John Deere hydraulic oil substitute. Let’s get started.

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What is John Deere Hydraulic Oil?

You may know John Deere equipment by the paint job—a mix of green and yellow. For many years, John Deere has been a household name for its drivetrains, lawn care, diesel engines, and other heavy machinery. John Deere hydraulic oil, also known as Hy-Gard, was first developed in 1973 by engineers employed by the manufacturer. The viscosity of the hydraulic transmission fluid is perfect for a John Deere because it was made solely for such equipment.

Furthermore, because of the polymeric viscosity improver included in Hy-Gard, it can be used across the board of John Deere machinery and equipment.

Physical Properties of Hy-Gard

Advantages of Using John Deere Hydrostatic Transmission Fluid

Wondering how good is good when it comes to hydraulic oil? Here is what Hy-Gard does when paired with John Deere equipment:

In fact, there are so many positive reasons why you should be using John Deere Hy-Gard for your John Deere machinery. What would ever prompt someone to search for a substitute? Well, if you are here, you are most likely already aware that John Deere’s hydraulic oil is insanely pricey.

What Makes John Deere Hydraulic Oil Expensive?

Ever since John Deere introduced Hy-Gard for its machinery, the oil has been some of the highest ranked and most competitive formulas available. Even as other manufacturers create new and improved versions of their hydraulic oil, John Deere continues to outrank all the rest. Because of that, it is also one of the most expensive. Simply put, the proprietary blend of ingredients in John Deere Hy-Gard oil increases the price.

Since machines cannot go without oil, it is not like you can just stop buying it.

What is an API Rating?

Let’s briefly discuss API ratings and why they are important. The American Petroleum Institute, or API, rates commercial motor oils based on certain criteria. For instance, they look at the OEM requirements and then check an oil against those points. The API will also certify the viscosity grade of oil suitable for a car’s engine.

If you are going to purchase a substitute for John Deere hydraulic oil, then you should look at API-rated oil. Not only does that ensure the freshness of what is in the bottle, but it also proves that the oil was matched for your equipment. However, you cannot rely on this rating wholeheartedly. Some API-rated oils may not be safe for your vehicle or John Deere mower.

Compare the properties of the API-rated substitute to Hy-Gard and decide from there. Or you can check our list of substitutes that are known to work.

John Deere Hydraulic Oil Substitutes

Ready to learn which oil substitutes exist? The following have been rated according to the oil properties, as well as their API rating. Do keep in mind that these substitutes should not be considered a 1:1 replacement for John Deere Hy-Gard. It is not advised to use substitutes in heavy machinery, but when you have no choice or need something as a replacement until you can get your hands on Hy-Gard, these are the ones you use:

Amsoil ATH 5W-30

The first John Deere hydraulic oil substitute is Amsoil ATH Tractor Hydraulic-Transmission Oil. This oil was designed to meet the specifications for JDM J20C and J20D. It has a viscosity index of 171, is fully synthetic, and has a point pour of -50°C. You can use Amsoil ATH in numerous ways, including conventional tractors. Being that this is an all-weather formula, you can expect it to retain the same viscosity whether it is hot or cold outside.

Additives were included to protect against rust and wear within the engine. Wet-brake chatter is dealt with using a friction modifier, and you also get better brake operation and less vibration. There is a lot of anecdotal evidence of Amsoil ATH being used as a genuine John Deere hydraulic oil substitute and working well.

Unfortunately, the price point of Amsoil ATH does not make it a clear winner, especially when you are trying to save a few bucks.

Mobil Fluid 424

Out of all these options, Mobilfluid 424 is the best equivalent to John Deere Hy-Gard oil. It meets the specifications for JDM J20C, meaning that you are going to get everything out of this fluid that you would expect from Hy-Gard. When used in your tractor, the oil flows smoothly through the hydraulic system and enhances the performance of your machine’s engine. Furthermore, it has the additives required to lubricate and protect the engine from damage.

Like John Deere Hy-Gard, Mobil’s 424 hydraulic oil and transmission fluid is resistant to oxidation and thermal breakdown. The formula is made to increase wet brake friction and extend clutch life. Mobilfluid 424 has a viscosity index of 145, a pour point of -42°C, and is used for agricultural and construction equipment. Interestingly, Mobilfluid 424 is also much cheaper than John Deere hydraulic oil, as well as two other competitors: Triax Agra UTTO and Amsoil Tractor oil.

The only downside to using Mobilfluid 424 is that it is not synthetic.

Triax Agra UTTO

Triax made its Agra UTTO Supreme a universal synthetic hydraulic transmission and wet brake oil for tractors and other agricultural or construction equipment. It is fully compatible with multiple systems, including those that use John Deere Hy-Gard. Triax Agra UTTO is slightly thicker than Hy-Gard, coming in at a viscosity index of 176. It has a pour point of -47°C and runs cheaply. For many, this is the go-to substitute for John Deere hydrostatic transmission oil.

All the elements are there, including smoother shifting and less brake chatter, anti-wear additives, and more. Triax Agra UTTO also lasts long and protects the system through all kinds of weather.

Citgo Transguard Lo-Temp

Although Citgo Transgard Lo-Temp is also advertised as universal transmission fluid and hydraulic oil (and meets JDM J20C specifications), it is not as widely talked about. That said, this motor oil does have plenty of advantages. Citgo Transgard Lo-Temp is a full synthetic that ensures your equipment has the right amount of heat transfer and friction while also acting as a drive fluid for power steering, braking, and take-off.

The one benefit of this formula is that it was designed to maximize functionality in cooler temperatures. If you are operating in a cooler climate, this might be the best bet for you. Machinery using Citgo Transgard Lo-Temp won’t see any diminished performance, even on the coldest of days.


Now, here is an option for when your John Deere riding or push mower needs its oil topped off. Valvoline synthetic motor oil should never be used for heavy machinery, even if you use 10w30. It’s simply not formulated to deal with that kind of engine. That said, Valvoline is a highly trusted brand for motor vehicles. You can add 10w30 to your lawn mower’s engine to reduce friction, control sludge deposits, and also regulate temperature. This is a highly affordable option to consider.

Schaeffer Synthetic Motor Oil

Within the Schaeffer lineup, you will find a range of full synthetic motor oil and diesel oil. Most formulas from Schaeffer boast superior thermal stability and protect against oxidation. These oils can run at higher temperatures since they resist breaking down. Schaeffer synthetic motor oil also does an excellent job at cleaning soot-covered engines while minimizing wear and tear. In short, this is excellent motor oil.

Disadvantages of Using a John Deere Hydraulic Oil Substitute

Now that you know there are substitutes out there that were designed to be the exact same as John Deere Hy-Gard, there is something you need to know. Yes, you can substitute your John Deere hydraulic oil with another brand and formula. However, some people recommend that you never substitute for something else. The reason is that hydrostatic systems are very sensitive to tampering. Also, there is a fair chance that you could void the warranty on your equipment.

Hy-Gard is indeed expensive, but it was formulated specifically for the hydrostatic system present in most John Deere equipment. You can use Hy-Gard for bulldozers, small tractors, and more.

Furthermore, you should never substitute anything for the transaxle. Also, do not use F-type fluids. Hy-Gard was designed to be thick and provide plenty of lubrication for your equipment. If you use a type F viscosity, you’re going to damage your John Deere. Moreover, while Hy-Gard has an SAE rating of 10w30, that doesn’t mean any 10w30 is fine.

Just because the viscosity rating of an oil is the same, it does not mean the chemical makeup is identical. Therefore, Hy-Gard is the best, but when you don’t have Hy-Gard, choose the closest substitute, such as Triax, Mobil 424, or Amsoil ATH.

Final Thoughts on Substituting Hy-Gard

John Deere hydraulic oil is expensive, and that can make it out of bounds for some people. Since you might need to pinch pennies, it is viable to look for substitutes that could do the trick. That said, you are going to need to find the right one. For agricultural or construction machinery and equipment, it is best to use Amsoil ATH, Triax Agra UTTO, or even Citgo Transgard. For lawn mowers and the like, you can use Valvoline or Schaeffer.