What Are the Signs of a Bad Transmission?

close-up of gloved hands working on transmission

Identifying Transmission Issues

There is oil in the engine and gas in the tank, the tires are aired up, but your car isn’t moving, so what’s the problem? One issue could be that the transmission has quit working. So what does the transmission do that a bad transmission could keep your car from moving? 

What to Look Out For

The transmission moves the engine-generated energy to the wheels and makes your car move. There are different types of car transmissions, each having a different ratio between the engine and the wheels. This ratio can determine how fast a car moves, or in cases where you need transmission repair, not move. This leads us to our next question. What are the symptoms of a bad transmission? There are six signs that your car needs transmission repair or maybe replacement: 

Doesn’t Respond or Slow Response

If your car hesitates to move or doesn’t move at all when it is in gear, you have a transmission problem. In an automatic transmission car, it will usually have a delay going between gears. In a standard transmission car, you may feel or hear the engine revving up, but find your car isn’t moving. 

Odd Noises and Sounds

Vehicles all have different noises, but when you hear an odd noise or sound like a buzzing, clunking, humming, or whining and find the car isn’t moving, you may need a transmission repair. Most transmission repair shops will offer free towing and inspection with a complete transmission repair or replacement. Strange sounds coming from the transmission while it’s sitting still are a concern for possible transmission repair too. 

Leaking Fluid or a Burning Smell

An automatic transmission requires fluid to keep the internal parts lubricated and working correctly. When that fluid leaks out, eventually the transmission will overheat and quit working. You’ll know when you have a transmission leak if you see a puddle of red fluid under your car. It also has its own smell, especially when it has gotten hot. 

Grinding, Jerking, or Shaking

Transmission repair or replacement may be needed if your transmission has been shaking, jerking, or has a grinding sound. It is often referred to by mechanics as a slipping transmission and can often be repaired by replacing or tightening existing transmission mounts. 

Transmission Won’t Go into Gear

This can happen while sitting at a signal light. You push on the gas, the engine revs up, and the car doesn’t move. As all the cars behind you begin honking and going around you, you keep giving it the gas only to have a revved up engine and a car that still isn’t moving. This could be a transmission repair that can be done by adding fluid, changing the screen, or flushing the transmission. You may also have a bad clutch or computer chip. If none of these repairs fix it, then you’ll need a new transmission. 

The Service Engine Soon Light

When the Check Engine Light comes on, you need to have your car examined by a professional mechanic. If that light comes on and the car isn’t moving, then your car probably needs a transmission repair or replacement. 

What happens when the transmission goes out?

When a transmission goes out, a car’s handling is affected. With a transmission slipping or vibrating, you could find it shifts differently, and it’s also possible the gear shift will stop working. 

Possible transmission repair or replacement can range from replacing the pump and changing the filter to installing new gears. Installation of new gears will require the transmission be torn apart, which is considered a transmission rebuild. 

A professional mechanic or transmission shop will inspect and test the transmission. They will then advise you on which option is needed for your car: transmission repair vs rebuild. 

What causes a transmission to go out, and why do transmissions fail?

There are many interrelated mechanisms and parts within a transmission. There are also many problems that can develop to cause a transmission to fail or simply quit working. While it isn’t going to be inexpensive, a  transmission repair is the less expensive option overall when it comes to replacement. Some common issues that can cause a transmission to fail and quit working are:

  • Leaking transmission fluid
  • Clogged and dirty transmission fluid filter
  • Broken transmission bands
  • Broken transmission gears
  • Faulty Torque Converter
  • Ruptured Transmission Seals

Leaking transmission fluid is something you can check yourself. There will be a puddle of red fluid under your car. Often a transmission repair will fix this by replacing ruptured transmission seals. Other times, it can be the bands have slipped, and a transmission replacement or rebuild will be required. You can also have the transmission filter changed and having new fluid added to your car will often fix issues such as a slipping transmission. 

close-up of gear lever in a car


If you are having car issues such as a transmission not working properly, take your car to a trusted mechanic or transmission shop. They will be able to tell when to repair the transmission as well as determine whether it needs to be rebuilt or replaced.