Common John Deere Tractor Transmission Problems and Fixes

9 Common John Deere Tractor Transmission Problems [& Fixes]

John Deere is perhaps one of the largest manufacturers of tractors in America. In fact, the company produces some of the best tractors and agricultural equipment in the world.

But any tractor is prone to problems especially transmission problems usually after several years of use and John Deere tractors are no different.

John Deere tractors can be fitted with several different types of transmissions but the latest models mostly come with hydrostatic transmissions.

That said, here are a few John Deere transmission problems and their fixes.


John Deere Transmission Problems

1. Hydraulic System Overheating

If you notice your hydraulic system overheating, that is the tractor overheating, there could be several reasons for the issue but it’s most likely got to do with the hydraulic transmission.

What’s worse is that the exact cause of the hydraulic system overheating issue is that it is a little tricky to diagnose and requires the use of a diagnostic tool.

How to Fix?

Until you take the tractor to a John Deere dealer to diagnose the issue, you can check the oil in the gearbox to see if it’s too thick and/or black.

If it is, you can change the transmission oil with the right oil.

2. Transmission Fluid Leaking

Another common John Deere transmission problem is leaking transmission fluid. This problem is easy to diagnose by looking under the hood of the tractor and checking for leaking fluid.

How to Fix?

The easiest way to fix the leaking transmission fluid issue is by closing the leak. Check the gasket and belts for damage and replace them if necessary.

3. Cold Hydraulic System Malfunction

The hydraulic transmission of your John Deere tractor may get cold at times even during use.

Signs of this issue are thick hydraulic fluid that is unable to reach the pump.

If ignored, the hydraulic transmission will not be able to dissipate heat, causing the transmission to run cold.

How to Fix?

A sign on the control dash should alert you about the temperature of the tractor and if it’s too cold or too hot.

In the event this happens, you will have to replace the transmission fluid.

But if this doesn’t fix the issue, you will have to get your tractor looked at by a John Deere dealer.

4. Hydrostatic Transmission Pump Failure

John Deere transmissions including the hydrostatic transmissions are fitted with an oil pump and are prone to damage over time.

When the oil pump fails, you will find it challenging when shifting gears instead of smooth shifting.

How to Fix?

The only way to solve the issue is by checking the oil pump for damage and replacing it with the correct model.

Refrain from buying cheap John Deere transmission parts and only buy from a reputed dealer.

5. Transmission Failure

In September 2917, John Deere recalled approximately 25,000 tractors due to a transmission failure.

This transmission failure could lead to a crash, however, no injuries were reported.

The recalled tractors were the D105 lawn tractors with serial numbers beginning with 1GXD105 that were sold by the company’s authorized dealers from March 2016 through August 2017.

6. Cavitation Problem

John Deere tractors may start with air or air bubbles in the transmission system – a process known as cavitation.

The pump should only contain oil and not air, and this shortage of oil fails to generate the pressure required to provide enough power to the transmission.

Cavitation usually happens when the tractor has been sitting all winter with fuel in the tank.

How to Fix?

Park the tractor on a flat, even ground, and top up the oil reservoir according to the specs.

Disconnect the transmission (refer to your owner’s manual).

Start the engine, move the gear to the neutral position, and disengage the brake pedal.

Lastly, push the motion control levers forward and hold them in position for a minute —this should purge any air from the transmission system.

7. Damaged or Failed Battery

The battery of your John Deere tractor provides power to the internal computer and electrical systems.

If there are any bad connections or a damaged battery, the tractor will not get enough current to the circuit to start up, and this low voltage can cause transmission issues.

How to Fix?

The battery of your John Deere tractor is located under the hood. Start the tractor to see whether it turns and stays on without any hiccups.

If it doesn’t, give the battery a boost to see whether this resolves the issue. If it doesn’t, then you will have to replace the battery.

8. Broken or Rusted Springs

Motors and springs in the John Deere transmission system can incur rust, which slows down the system and eventually causes long-term damage.

How to Fix?

Open up the hood and check for any signs of rust. Rust may occur after a period of time. If there are any rusted bolts, springs, or screws, they will have to be replaced.

9. Transmission Not Shifting Properly

If you’re having trouble shifting gears of your John Deere tractor is making grinding noises when shifting gears, that’s definitely a transmission problem.

If you’re experiencing these issues, the only option is to have the tractor checked by a John Deere technician.

In most cases, this issue can be fixed, and the transmission may have to be replaced in worse cases.


Which transmission type is best in a tractor?

Gear-drive transmissions are regarded as the best transmissions for tractors.

But tractors with hydrostatic transmissions are easier to operate than gear-drive transmissions.


What is transmission system of a tractor?

A transmission system of a tractor is designed to transmit power generated in the engine to the tractor’s hydraulic system, wheels, and power take-off system.


Final Thoughts

Buying a tractor from the John Deere hangar is a great investment. But just like any other brand, John Deere can incur transmission problems.

The 9 problems on this list are the most common with John Deere tractors and while more of them can be fixed easily, others may require technical assistance.