8 Most Common John Deere Z445 Problems

The John Deere Z445 is a zero-turn lawn mower like the Z930M from the same brand.

This Kawasaki-powered riding mower is powerful for its size, boasting a respectful 25 hp, which is more than enough for most gardens and small fields.

However, some models seem to have a few issues, especially those produced in recent years.

Users complain about engine, transmission, muffler, and steering wheel problems.

Let’s look closely at the most typical John Deere Z445 issues and see how to fix them.

The most common problems with John Deere Z445

The curious issue with this lawn mower from John Deere is that older models seem to work better than newer machines.

Many users who purchased this zero-turn mower between 2007-2011 have almost only good things to say, but users who have later models (2014 and later) seem to encounter the most issues.

This could be one of those rare cases where the advancement of technology has brought more damage than solutions. Whether John Deere is taking notes of these problems remains to be seen.

Many of these issues are relatively familiar with lawnmowers but still a hassle.

That’s why we compiled this list of the most common issues related to this John Deere mower, and we offer a few ways to troubleshoot or fix them.

1. Exhaust issue

This John Deere model has a few issues with its engine, including starting problems (similar to the 1025r model), ignition issues, and general bounciness of the vehicle.

Given that the Z445’s engine is one of the most complexes on the market, it is challenging to complete tasks without assistance.

Luckily, the most common problem seems to be the exhaust issue provoked by a clogged gas cap vent.

If this vent is blocked, the exhaust cannot exit, which may lead to various engine issues.

The easiest fix would be to replace the clogged gas cap vent with a new one, and if you have some experience, you can do it yourself and save on the repair costs.

2. Transmission issue

For beginners, it’s worth knowing that the transmission of a mower is supposed to convert the engine’s electrical energy into mechanical energy for the wheels.

Given that the John Deere Z445 is a zero-turn mower with hydrostatic transmission, the hydraulic pump is one more step before the electrical power turns into mechanical power.

The electrical power goes through the hydraulic fluid, which transfers this power to the wheels.

Many users experience more than one transmission problem because of this, usually related to the state or level of the hydraulic fluid, but sometimes also because of mechanical issues in the hydraulic system.

Here are a few tips to fix/prevent future hydrostatic transmission problems:

1. Keep the oil level in check and add more when needed.
2. Refresh the hydraulic oil when it changes viscosity (often due to temperature or long-time disuse).
3. When you haven’t used your mower in a while, the air inside the pipes will prevent the wheels from receiving the necessary power. Consult your manual to learn how to remove excess air.
4. Check all the connections in the mower hydrostatic transmission for damage or leakage.

3. Spark plug issue

The spark plug is quite an issue for many John Deere models.

It’s not the company’s fault, but rather the nature of the plug itself that calls for regular maintenance to keep it working correctly.

Spark plugs get covered with burned gasoline every time you use the mower, preventing them from working as they should and igniting the engine.

Luckily, this component is easy to troubleshoot and clean, and it’s very cheap to replace.

Remove it from the engine, including all dirt and debris, if you have time.

However, it’s so inexpensive that you might as well replace it with a new one, mainly because your old spark plug begins to rust after a while.

4. Safety issue

As we mentioned, the engine of the Z445 is one of the most complex ones on the market, and as such, John Deere has introduced a few safety measures to prevent mishaps.

The problem that many users encounter is that these safety measures are the ones that cause issues with the engine, sometimes stopping it in the middle of the action.

Here are the most common situations where the engine stops for safety purposes:

1. The mower is set to reverse gear, and you’re using the cutting deck.
2. The cutting deck is clogged by something that prevents the correct functioning of the blades.
3. An electrical problem with the wire harness signals that the mower is moving in reverse, but there’s no one in the driver’s seat.

For point 2, it’s enough to remove the clog to solve the issue, but for point 3, you should refer to a professional to fix the electrical system.

5. Muffler issue

The most pressing issue about the John Deere Z445 is indeed the muffler.

Many people disapprove of this design choice, for the muffler is way too close to the ground.

This means the muffler will burn the grass underneath when you stop the mower for longer than a minute.

This is a real impediment for land owners, as it often happens during mowing that you need to stop to pick up a stick or for similar reasons, and it’s not possible to wait for the muffler to cool down every time.

Unfortunately, there is nothing to do about this issue except report it to John Deere, and I hope they will take note of it and find a fix for it in future models.

6. Steering issue

The steering wheel is a fundamental part of the machine; any minor issue should be checked and fixed immediately.

Many Z445 users have reported motion control issues with the steering wheel, which are summarized in two main scenarios:

1. One of the steering arms doesn’t respond, while the other functions as usual. Look at the control rod to see if it’s properly connected to the motor. Also, check the connection between the arms and the engine.
2. One of the steering arms is stiffer than the other. You can check this when applying full throttle to both arms. If the mower moves in one direction (right or left), the arm overpowers the other. Check the bolt at the control’s arm base, which regulates speed and motion. 

7. Cutting deck issue

Apart from the muffler, it seems that in models produced from 2014 onwards, the cutting deck has other issues.

These issues also depend on the size of the deck. 48” deck turns better around trees and small items when compared to a 54” deck.

On top of this, the mower deck does an excellent job at cutting on flat surfaces but doesn’t perform as well going uphill or on uneven ground, so that’s something to keep in mind before you buy this model.

8. Brakes issue

To stop the John Deere Z445, you will need to pull a lever to control the transmission system and hence, the engine. Easy peasy, right?

Well, not quite. Many reported parking the mower because the lever gets jammed or the mower won’t park properly.

Usually, the main issue with the brakes is that the lever gets covered in debris and rust over time. So you should lubricate the lever every other day and perform regular maintenance to remove rust.

If you cannot park the Z445 mower even after all these issues have been fixed, a mechanical problem with the brakes should be immediately addressed by a professional.

John Deere Z445 problems: are they a deal-breaker?

We wouldn’t say so because the Z445 zero-turn mower is known as being a powerful and long-lasting machine.

The muffler is undoubtedly the most annoying problem since it’s something that can’t be changed.

However, it’s worth noting that most issues with this model seem to come from machines produced in recent years.

So if you’re looking to buy a Z445 mower, you could try to look for one of the first models, which seems more reliable.

Marvin Tucker( Farming Equipment Expert )

Marvin is an expert in farming equipment with a strong background in agricultural engineering. He graduated from Kansas State College of Agriculture, where he received a degree in Agricultural Engineering and specialized in farm equipment design and maintenance.