7 Most Common Automatic Transmission Problems

Transmission Fluid

Your automatic transmission is a critical system in your vehicle and needs proper care and attention by you to ensure long lasting operation. Many people are unaware that the automatic transmission can cost more to replace than an engine. This makes it important that you pay attention to the following symptoms and problems on this page if you want to avoid a major repair.

Automatic Transmission Symptoms In This Page:

  1. Grinding or shaking sensation in gear
  2. Car won't engage or respond when in gear
  3. Makes Noises: whining, humming or clunking, noisy in neutral
  4. Smells like its burning
  5. Gears Slipping
  6. Low or leaking fluid
  7. Check engine light is on

This article may ease your mind, or it may make alarm bells go off in your head. Either way we aim to help you with the information below. Armed with the right knowledge, you can make a well-informed decision about what to do (if anything).

These Automatic Transmission Symptoms Are Telling You to Pay Attention

Your Automatic transmission is a very complex mechanical and computer driven system. Because of that your automatic transmission can be more expensive to repair than your engine (depending on your particular car). That means you are better off paying attention if one of these symptoms appear rather than ignoring or waiting for it to go away. It can cost you a lot of inconvenience and money if you neglect its service.

1. Grinding or shaking sensation in gear

Your automatic transmission normally operates smoothly when shifting from gear to gear. You shouldn't feel any grinding, slipping or shaking sensations as your car switches gears. When a transmission is starting to have problems, these symptoms can seem insignificant. But, it is best to pay attention at this point because it will likely become worse with use. If you are already feeling pretty jarring sensations when the car shifts, it's time to get it in have us look at it. Normally when automatic transmissions have damaged gears they progressively get worse.

Summary: This is a more serious problem and time is very important. Be sure to get your car to a qualified automatic transmission specialist soon.

2. Car won't engage or respond when in gear

When you put your car into drive or reverse does it respond immediately or is there a delay? Does the car's transmission not engage at all when you put it in drive or reverse? These are both issues that may signal a problem. It could indicate a problem with your fluid whose protective properties have degraded and has become thick. In this case a good fluid exchange could help you.

Other times you may be experiencing a computer system problem. Sometimes resetting the car's computer can solve the problem too. You can do this yourself by disconnecting the battery for around 30 minutes. This can allow it to reset. If this doesn't help, it's time to let a qualified transmission mechanic take a look for you.

Summary: When your automatic transmission doesn't engage or delays, it's time to have someone look at it. Most problems from these symptoms are minor, but it's best to find out for sure so that it doesn't cost $1000's later.

3. Makes Noises: whining, humming or clunking, noisy in neutral

If you suddenly start to hear a whining, humming or clunking noise under your car like you've never heard before, you may have transmission trouble. That trouble may likely be minor, but it could signal something worse.

Some noises that come from your transmission can be caused by your automatic transmission fluid breaking down. This fluid has a hefty job of keeping an amazing amount of mechanical gears and components lubricated. With time and use, that fluid loses its protective properties and doesn't stop that friction. Friction is what damages that complex automatic transmission system.

If you hear clunking noises and suspect it's coming from the transmission, your transmission may already have an internal part giving out. If that's the case, it's important to have a qualified automatic transmission mechanic look at it right away.

Summary: Some noises may be simple problems due to your transmission fluid, while other times it maybe more serious. Certainly check your automatic transmission fluid if you can. If you're low, add some and get into the shop soon to talk with one of our transmission mechanics about the issue. If you're not sure and need peace of mind, call or visit the shop right away.

4. Smells like its burning

Your car should NOT have a burning smell and this is something to be concerned about. One of the most common causes of a burning smell from the transmission is overheated fluid. Your transmission's fluid has a super-important role in protecting this very expensive and complex system running properly. Mainly it is lubrication.

When your transmission fluid's lubricating abilities diminish, as it does with time and mileage, it enables damaging friction between all the parts. Friction causes the breakdown of parts and buildup of debris and likely sludge. All of these problems together eventually lead to a complete transmission breakdown. That is expensive and quite inconvenient.

Sometimes the cause is simply low transmission fluid level. That is usually caused by a leak because in most cars unlike motor oil, transmission fluid doesn't lessen with time. Also, this can happen with the wrong type of fluid added to your particular vehicle.

Summary: If you smell burning from your transmission it’s time to act before it’s a big problem. Check your fluid level if you know how and call or visit us to find out the cause and ease your mind.

5. Gears Slipping

Does your car slip out of gear or lose traction when you need it? This is a serious safety problem if so. If your transmission is slipping in and out of gears when you’re behind the wheel, and you need to give it the gas to avoid a problem, that is scary.

Your car’s computer tells the transmission when to shift between one gear and another. It tells your car when to send power to your wheels. If something is malfunctioning here the signal is not being properly sent.

Summary: Slipping gears is a serious safety issue.If your car’s automatic transmission is slipping in and out of gears, call or come by the shop, right away – safely. If you feel like you can’t trust your car to drive it here, call us and we can arrange a tow for you.

6. Low or Leaking Transmission Fluid

Have you seen a bright red or possibly dirty dark red fluid on your driveway or garage floor? You are likely seeing Automatic Transmission fluid. Because transmission fluid should never leak, this could lead to a very serious and complete breakdown of your transmission – which is very inconvenient and costly (often more than a new engine).

Unlike motor oil, transmission fluid does not normally lessen due to time and mileage. So, if you’re seeing that you are low on transmission fluid, then you have a leak somewhere. Low fluid can create great friction in your transmission which will breakdown parts inside and eventually lead to a complete transmission breakdown.

How serious is low or leaking transmission fluid? If you do nothing, it will turn into a very serious problem. But, it doesn’t have to be that way. Sometimes a leak is a low cost service just to replace a leaking gasket or possibly a hose. Just remember, don’t neglect a small problem in your transmission unless you want a big problem later.

Summary: Leaks and low fluid are not normal in your transmission. The repair is likely a smaller one if you catch the problem early. Look for red fluid under your car to tell if you have a leak. Get it into the shop right way before it’s a big problem.

7. Check engine light is on

Your “Check Engine” light is there to help you know there is a current or upcoming problem in your car. But the light can indicate a problem from many different systems in your car, not just your transmission.

Your transmission contains numerous sensors that can pick up anything unusual in your transmission – much more than you can. These sensors send signals to your computer that something is wrong. Then, the check engine light passes on that message to you that something is wrong.

Why have the check engine light checked out? Well, that’s because if the problem is related to your transmission and an early detection indicates a problem, your solution may be small. If you wait, you could have just caused yourself a whole lot of unnecessary grief and money.

Summary: If your check engine light is on, have it checked immediately. It may be a very small thing that your computer has sensed and could save you 1000’s due to a repair.


Many problems with your transmission start off small. Ignoring the signals like the symptoms listed above usually lead to super-costly repairs. Some repairs are small and affordable and they can prevent a huge bill later on. If peace of mind and your money is important to you and you experience any of these automatic transmission problems give us a call or bring your car by the shop to get our opinion.

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