How Does a Hydrostatic Transmission Work on a Riding Lawn Mower? (Solved & Explained!)

A motor will power a series of hydrostatic pistons. These pistons will then drive the drive wheels on the lawnmower. 
The pistons will be filled with oil. This is a contrast to standard pistons on a lawnmower which will often be belt driven. 

What is the benefit of a hydrostatic lawnmower? 

Hydrostatic lawnmowers will often have more power than a standard lawnmower. You will find that they move a lot faster, and they cut that much better. 
The main benefit of a hydrostatic lawnmower is the fact that they are easy to move around. They have a much tighter turn radius than a typical lawnmower. 

Are hydrostatic lawnmowers easy to maintain? 

In theory, yes. A hydrostatic lawnmower that is not maintained properly will be more expensive to fix than a standard lawnmower. However, these lawnmowers tend to require less maintenance than your typical lawnmower. 

Are hydrostatic lawnmowers expensive? 

Yes. They will be much more expensive than standard lawnmowers, mostly down to the fact that they use non-proprietary technology. It is up to you to work out whether it is worth spending the extra cash on one of these lawnmowers. 

Are hydrostatic lawnmowers good for residential homes? 

The high cost means that many homeowners will turn away from them. However, the fact that they have a tighter turn radius can make them ideal for smaller gardens. 

Which company makes the best hydrostatic lawnmowers? 

Any of the big brands in the world of lawnmowers will have hydrostatic options. Most people do tend to prefer the products produced by John Deere. 

How do you know if a lawnmower is a hydrostatic lawnmower? 

It will be included in the marketing materials for the lawnmower. If the product specification doesn’t say that you have a hydrostatic lawnmower, then you don’t have a hydrostatic lawnmower. 

How long will a hydrostatic transmission last? 

This will be dependent on the product that you have purchased. It will also be dependent on how well you maintain the transmission. 
Generally speaking, you are going to be able to get a good 3,000 to 5,000 hours out of the transmission. This should be fine for almost everybody. 

Can you maintain a hydrostatic lawnmower yourself? 

Yes. However, it is important that you read through the manual that came with your lawnmower. This will tell you everything that you need to do to maintain it properly. 
Bigger maintenance jobs will need to be carried out by a professional. Make sure that you always use an authorized repair agent for any repairs that you want carried out. 

How often do you need to replace the oil on a hydrostatic lawnmower? 

Not that often. These are sealed units, which means that the oil will not get filthy. Nothing can get inside. 
Most people recommend that you have the oil replaced every 1,000 hours by a professional. The manual will tell you exactly when the oil should be replaced. 

Do hydrostatic lawnmowers use more fuel than a standard lawnmower? 

Because they are slightly more powerful, yes. However, we doubt that it is going to drastically increase the cost. Maybe a couple of dollars per season, and thus it isn’t really something that you need to worry about. 

Do you need to winterize a hydrostatic lawnmower? 

You would winterize your hydrostatic lawnmower in the same way that you would winterize a standard lawnmower. This means removing the fuel and following the winterization instructions detailed in the manual. 
Because the transmission fluid is located in a sealed unit, you do not have to worry about winterizing that. 

Why does my hydrostatic lawnmower make a whining sound? 

This is normal for hydrostatic lawnmowers. It is air inside of the pistons. It is a sound that you will need to get used to. 
It is likely that this is going to be more of a problem when you are driving at high speeds and then choose to drop down to idle quickly. 

Are hydrostatic lawnmowers louder than normal lawnmowers? 

They make different sounds. However, a hydrostatic lawnmower is going to be no louder than a standard ride-on lawnmower.  

Is there a clutch on a hydrostatic lawnmower? 

No. There will not be a clutch on a hydrostatic lawnmower. This is because there are no gears that need to be changed by the user. 

How do you change the speed on a hydrostatic lawnmower? 

This will be dependent on the product that you own. Most of them will have a speed selector in the cockpit that you can move up and down. 

Do hydrostatic lawnmowers have cruise control? 

A lot of top companies are now starting to put cruise control into their hydrostatic lawnmowers. This will be clearly highlighted in the vehicle specifications if this is the case. 

Are hydrostatic lawnmowers easy to use? 

Yes. Because the user does not have to worry about fiddling with the gears themselves, hydrostatic lawnmowers are often seen as a great option for people. You don’t really have to think about much other than the speed that you want to travel at. 

Can hydrostatic lawnmowers move up hills? 

Yes. There is no real difference in what a hydrostatic lawnmower and a normal lawnmower can cut. The hydrostatic lawnmower will be able to cut up hills. 
It could possibly be argued that hydrostatic lawnmowers will find it a bit easier to get up a hill, owing to the increased amount of power that they have. 

Why did my hydrostatic lawnmower transmission slip? 

This could indicate that the oil inside of the hydrostatic transmission will need to be replaced. While you could potentially replace this yourself, we recommend that you talk to a professional. This will ensure that the problem is dealt with properly. 

Do you put automatic transmission fluid in a hydrostatic system on a lawnmower? 

No. They are not the same type of oil and this would result in your hydrostatic lawnmower breaking. 
There will be information about the type of oil that you should be using in the manual. Make sure that you follow these instructions perfectly. 
To ensure that you get the right oil, we suggest heading to a professional.