List of Most Common G56 Transmission Problems (5 Genuine Solutions)

In this brief guide, we are going to provide you with common problems with G56 transmission and what you can do to rectify these problems before they worsen.

G56 is a manual transmission and one of the most popular transmissions on the road. It is the only manual transmission being optioned in Class-4 and Class-5 trucks.

Manual transmissions have a global reputation for quality, reliability and durability. However, there are many problem with manual transmissions and we’ll tell you why and how you can solve them

What are the common problems with G56 transmission?

Some of the most common problems with G56 transmission are:

  • Clutch malfunction 
  • Transmission failure
  • Difficulty shifting
  • Transmission overheating
  • Burning smell

Why is Clutch malfunction a problem with G56 transmissions?

If you’re Clutch or if you are not getting the desired response when you release the brake and press the throttle pedal then you are most definitely experiencing Clutch malfunction.

What are the signs of this problem with the G56 transmission?

Firstly you would be unable to stop the car when releasing the throttle pedal for disengagement problem and secondly for engagement from even if you press too much throttle the car will not move forward.

How to solve this G56 transmission problem?

If the clutch of the torque converter is worn out then you need to replace it or else the solenoid might be broken which also might need replacing. In the worst case the entire assembly needs to be replaced if the state of the torque converter is beyond repair.

Why is Transmission failure a problem with G56 transmissions?

The G56 transmission system is not designed to slip and if you are experiencing slippage then it could cause slow response or further damage to the transmission system. So, it is definitely a sign of a problem with the mechanical components of the transmission leading to failure.

What are the signs of this problem with the G56 transmission?

You will be able to hear the gear slip while driving and this would be a good sign if there is slipping. Also, an error code will be displayed if you use a diagnostic tool.

How to solve this G56  transmission problem?

The shifting cams of the two gears might be worn out and need to be replaced. Also, there is a chance that these cams might also be broken. Rarely, complete mechanical failure occurs with these transmissions.

Why is Difficulty shifting a problem with G56 transmissions?

You would want a seamless and easy shift even at low throttle input, so if your G56 transmission is shifting harshly or with difficulty even at low speed then there is definitely a problem.

What are the signs of this problem with the G56 transmission?

You would immediately notice and sense if the G56 transmission is shifting with difficulty from one gear to another as this is one of most important issues with GM.

How to solve this G56  transmission problem?

Firstly try replacing the transmission pressure sensor, if that doesn’t work then check for an oil leak in the servo assembly of the particular gear. These are primarily two fixes for this problem.

Why is Transmission overheating a problem with G56 transmissions?

Because G56 transmission mechanical components tend to get damaged, worn, and malfunction under high heat levels. This results in lower than the acceptable performance from the vehicle and high fuel consumption as well as lowering the life of the gearbox.

What are the signs of this problem with the G56 transmission?

Generally when a G56 transmission overheats an error is shown. This error is not immediately visible on the screen but requires a diagnostic tool to get these actual error codes.

How to solve this G56 transmission problem?

After cooling down the transmission check the gearbox oil for its condition. Change it if it is too thick and completely black. Also, check your clutch if it is the problem behind this malfunction.

Why is Burning smell a problem with G56 transmissions?

If you get a burning odor, your G56 transmission fluid is probably overheating due to clutch debris, breakdown of metallic components and sludge. So this sign is a cause for concern.

What are the signs of this problem with the G56 transmission?

The smell itself should be a good sign that there is something wrong with your G56 transmission. However you will get a more detailed sign if you use a software diagnostic tool.

How to solve this G56 transmission problem?

Check the transmission oil and its level. If it is too low then fill the required amount of oil in the transmission. If it is too dirty, then drain the entire oil from the transmission and fill it again. Also check for any debris and discarded materials.

How to precisely diagnose these common problems in G56 transmission?

To properly diagnose these problems, you need a scan tool to read these codes from the Transmission Control Unit. Firstly, If a G56 transmission is malfunctioning, it immediately informs the driver with an error message on the screen.

How to prevent getting these problems in the first place?

Regularly changing your gearbox oil and other lubricants may save you a lot of trouble and money in the future. Although many experts suggest different number miles for servicing, your car manual will give you a proper recommendation when you should change it.

FAQs: G56 transmission problems

Is the G56 a good transmission?

The G56 is a good transmission and is quiet with a stock clutch. After  trying many fluids in the transmission and with the stock clutch the amsoil mtg is the smoothest best fluid in mechanic’s experience. Many options for aftermarket clutches which will make it louder in certain situations.

How long will a G56 last?

There are incidents where the original clutch in a G56 transmission has lasted in excess 100k miles. There are also situations where the clutch starts to slip at 15k miles. Generally speaking, you want to watch for the warning signs above. If you notice these issues on a consistent basis, it’s a good idea to inspect the clutch.

Conclusion

In this brief guide, we have provided you with common problems with G56 transmission and what you can do to rectify these problems before they worsen.

If you have any questions or comments please let us know.

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