(Updated on November 3, 2022)
The transmission is one of the most important parts of a vehicle. Without it, getting to your destination would be near impossible. In a nutshell, the transmission works by redirecting engine power to the driveshaft so that the wheels of the car can rotate.
If you take care of your car and bring it to the shop for maintenance on a regular basis, then most likely you will not have any major problems with your transmission for a very long time. In fact, you should be able to get at least 100,000 miles out of your transmission before any problems arise.
You will want to properly maintain your transmission because replacing a faulty transmission can cost you thousands of dollars. This means it’s extremely important to resolve minor transmission issues before they become serious ones.
When your transmission first starts going bad, you may hear some strange noises coming from it. These noises will be most noticeable as you switch gears. Remember that the transmission is connected to the gearbox, which is a device that gives drivers the ability to switch gears.
When you switch to a different gear, the engine adjusts its speed and power to accommodate this new demand being put on it. The rotating components of the transmission speed up during this process because the transmission is now redirecting this new engine power to the driveshaft.
Top 4 Reasons Transmission is Making Noise
Remember that transmission noises do not necessarily mean your transmission is already bad. But they could be a sign that you need to fix or replace something in the transmission soon or else it will get much worse. It may even impact your engine too. So, the best way to stop the noises is to figure out what exactly is causing them.
Below are the top 4 causes of transmission noise.
1) Old Transmission Fluid
If you look at the owner’s manual of most economy cars, they will tell you that the transmission fluid should last anywhere from 50,000 to 100,000 miles. If your transmission fluid has not been changed after your car has traveled this many miles, then it means your fluid is too old, likely burnt, and must be replaced.
Old transmission fluid leaves varnish debris on the moving components of the transmission. This varnish debris forms after the fluid has gotten too old. If the debris remains on the components, those strange noises are going to be heard, especially if the filters are clogged.
2) Low Transmission Fluid
Just like how having sufficient motor oil is essential for the wellbeing of your engine, you need to check your transmission fluid level to make sure it’s where it needs to be. The main purpose of transmission fluid is to lubricate all the metal components within a transmission.
If there is not enough transmission fluid, metal on metal contact will result. Not only will this cause strange noises, but the gears inside the transmission will start to wear down. If you allow it to go on long enough, damage and subsequent transmission failure will be the result.
3) Petroleum-based Transmission Fluid
There are many types of transmission fluids available on the market today. In the old days, there used to only be petroleum-based transmission fluid which would cause varnish deposits to form quickly. It would only take a couple of years for the filters to get clogged and prevent the normal flow of the transmission fluid.
If you are still using this type of transmission fluid, then it will cause more heat and friction from the moving components of your transmission. This will mean more unpleasant noises will be heard.
Fortunately, the quick solution to this problem is synthetic transmission fluid. Just replace the petroleum-based fluid with the synthetic fluid and then all those nasty debris will be washed away. Synthetic is formulated to have extra amounts of lubrication strength to ensure the components stay cool.
See Also: Transmission Fluid Change Cost
4) Bad Torque Converter
The transmission depends on the torque converter to allow it to shift gears properly. There are needle bearings in the torque converter which may get damaged or worn out after a while. If this were to happen, your transmission will make unusual sounds whenever your driving gear is set.
These are often grinding noises which will be annoying to hear. If you set it to the neutral gear, then the sounds will stop. This is a clear indication that you need to replace your torque converter.