How Automatic Transmissions Work

By Mister Transmission

Your vehicle’s automatic transmission is a remarkable piece of machinery. It may be complex to understand how it functions, but a little knowledge can go a long way toward preventing a breakdown

The most complex and intricate system in your car is its automatic transmission – understanding how it works can help save you time, hassle, and money. Comprised of a series of mechanical, hydraulic, and electrical components, they are all controlled by your car’s engine control unit, aka the powertrain control module.

A short drive to a nearby store means your transmission will likely shift about 25 to 30 times. Now imagine how many trips like that you make in a year and the impact they have on your transmission.

Shift Your Thinking about Your Automatic Transmission

Automatic transmission gear changes are monitored and executed by your vehicle’s internal computer. A torque converter uses the pressure and flow of transmission fluid to not only regulate the gear changes but also to allow the engine to continue running even when at a full stop. It also makes for a smoother shifting between gears.

When fluid levels in the transmission drop, so does the pressure that controls the shifting of gears. That can cause friction and less effective cooling, in turn leading to damage and potentially expensive repairs.

Recognizing Automatic Transmission Warning Signs

Preventing a breakdown from stranding you at the roadside requires insight into the warning signs your car will send if you’re on the cusp of experiencing a transmission-related problem. These warning signs include:

  • Grinding, rattling, or whining noises when changing gears or problems shifting gears
  • A delay in movement or your car jerks or shakes as it accelerates
  • Your transmission fluid is low, or you notice it pooling beneath the engine where you park
  • If you check your transmission fluid and see it’s not a reddish colour
  • You smell a burning odour while or after you drive

If you suspect your vehicle’s automatic transmission isn’t performing properly, or if you have questions about preventative transmission maintenance, contact us. Take advantage of our free 21-point multi-check inspection and avoid the cost and aggravation associated with a failing transmission.

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Customer Reviews
i walked in as someone...
Amanpreet Kaur
i walked in as someone who doesnt know much about cars and got the amazing service !!! thank you
Date: April 29, 2026
Website: Google
Great communication and helped me...
Jeremy Dreise
Great communication and helped me to understand what was needed. Detailed bill and explanation was fantastic.
Date: April 28, 2026
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I was having transmission problems...
Matthew T
I was having transmission problems with my Ford pickup truck. Called mr transmission and Jason got me in right away. They had a diagnosis the next day and I went ahead with the work. Jason was great to deal with. Good communication and im happy with the service.
Date: April 28, 2026
Website: Google
Barry and team were outstanding!!...
Timothy Theivendrarajah
Barry and team were outstanding!! I would highly recommended!!!
Date: April 28, 2026
Website: Google
Called for estimate on transmission...
Pran Jai
Called for estimate on transmission flush and was advised they only do repairs now. However, he was very helpful and provided more details on the type of work my car actually needs and saved me a couple hundred dollars of irrelevant maintenance. Seems like a honest shop.
Date: April 28, 2026
Website: Google
Really appreciate their help on...
Pavithra Rankiri
Really appreciate their help on issue I had with my car. Friendly expertise service anyone can count on.
Date: April 27, 2026
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Kyle went above and beyond...
Tom Frobb
Kyle went above and beyond to answer all of my questions. I would recommend the shop
Date: April 27, 2026
Website: Google
I had an issue with...
DZIOB963852963
I had an issue with my 1999 Toyota 4Runner—the clutch pedal was almost on the floor, and shifting gears was difficult. I took it to Mister Transmission at the Dixie location, where the problem was quickly diagnosed and fixed. Despite the car being 27 years old and the parts not being easy to find, they got me back on the road the same day. The staff were very competent and friendly, the service was fast, and the price was reasonable. I highly recommend this place.
Date: April 26, 2026
Website: Google
I brought my car in...
Nicole W
I brought my car in to have the clutch replaced back in March. I was in a rush to get my car in somewhere, and after having been quoted $5k by the dealership, the staff at Mister Transmission accommodated me within the hour and did the service for $1k less than the dealership. Later, there was an issue with the battery when the car was returned home and they looked at it for me at no cost. They even called a week or so later to make sure that the car was running okay.All around great service, great prices, and friendly staff. Thanks a bunch!
Date: April 26, 2026
Website: Google
I had an issue with...
DZIOB963852963
I had an issue with my 1999 Toyota 4Runner—the clutch pedal was almost on the floor, and shifting gears was difficult. I took it to Mister Transmission at the Dixie location, where the problem was quickly diagnosed and fixed. Despite the car being 27 years old and the parts not being easy to find, they got me back on the road the same day. The staff were very competent and friendly, the service was fast, and the price was reasonable. I highly recommend this place.
Date: April 26, 2026
Website: Google
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