Transmission Parts

By Mister Transmission

Transmission parts knowledge for people researching how transmissions work.

A transmission is an impressive puzzle to most drivers, made up of many intricate connections among a multitude of transmission parts. The complexity of these parts and how they fit together is intimidating, especially if you’re facing transmission repairs and you don’t understand what’s happening or why.

While we need to trust our transmission mechanics to take care of the specifics, knowing a little bit about the transmission parts that might be malfunctioning can help to set your mind at ease during the transmission repair process.

The first step to a basic understanding of transmission parts is to understand the purpose of the transmission as a whole. Your automatic transmission is responsible for transferring the power of your engine to the drive shaft and wheels so that your car can move within its optimal range of revolutions per minute (RPM). The transmission maintains this optimal range by shifting transmission gears as you drive faster or slower.

 
The main transmission parts that need to work together are:
  •     Planetary Gear Sets
  •     Hydraulic System
  •     Torque Converter
  •     Computer
Planetary Gear Sets

Manual transmissions use a clutch to connect the engine and transmission. They require the driver to shift the transmission gears, which means actually moving the gears in a somewhat linear, sliding transfer to engage with the coordinating gears needed to maintain the proper RPM ratio. Automatic transmissions keep the transmission gears in one place, in a more circular structure. This is not unlike a small solar system, hence the name Planetary Gear Sets.

Using the combination of an outer ring gear, a central “sun” gear, and two or more smaller “planet” gears, which are all constantly meshed together, the transmission takes over the gear shifting from the driver. Much like the solar system, the sun gear is in the centre and remains stationary and the smaller planet gears engage with it and the ring gear to keep the car moving smoothly.

The ring gear is connected to the input shaft, which brings power from the engine. The planet gears exist within a casing or carrier that is connected to the output shaft which carries power to the drive train and wheels. The planet gears are also connected to a clutch pack. The sun gear is connected to a drum, which is connected to the other half of the clutch pack.

Transmission clutch packs are a series of disks, half with splines on the outside edge, and half with splines on the inside edge. These alternating disks are made to fit together to lock and turn together. They do this using hydraulic functionality.

Hydraulic System

All of the transmission parts are constantly submersed in transmission fluid. This fluid is manipulated to create pressure, which pushes the transmission clutch pack together at the right time. A complex system of tubes moves the fluid around the transmission and torque converter to create this pressure. The transmission hydraulic system has three main purposes: to help control transmission gear shifting, to lubricate the transmission parts to prevent friction damage, and to keep the transmission cool. The fluid pressure within the transmission must be maintained at all times to prevent damage.

The tubes that transfer the transmission fluid have two major external seals at the front and back. The seal at the front protects the connection with the torque converter and the rear seal contains the fluid where the transmission meets the output shaft. Seals are made of neoprene. Within the transmission exists another type of seal, called a gasket, which connects and protects two stationary transmission parts. Gaskets may be made of any of a variety of materials, such as rubber or silicone. Seals and gaskets can harden over time, which might cause leaks and a drop in transmission fluid pressure, both of which can lead to damage to the transmission.

Torque Converter

When driving a manual transmission, the driver must engage the clutch or shift into neutral when the vehicle comes to a stop, such as at a red light, or the engine will stall. The torque converter in an automatic transmission allows the engine to continue running when the vehicle is stopped yet still in gear. Torque is defined as a force that causes rotation. The torque converter uses the pressure of the transmission fluid to control the rotation of its parts. When you are stopped at that red light, one half of the torque converter is turning while the other is stationary. When you accelerate, the fluid pressure forces the other half to spin in conjunction with the first half so that vehicle moves forward.

Computer

In most cars today, a computer controls the transmission’s function allowing all vehicle systems to work together for optimum fuel economy and power. As many as 30 sensors read all of the various factors such as vehicle speed, engine temperature, engine speed, etc, that control transmission gear shifting to ensure the optimal shift points are used.

The many transmission parts in your vehicle may remain a puzzle, but understanding some of the basics can help you to have a more informed conversation with your transmission mechanics before leaving it in their capable hands.

As Gene Lewis at the Moncton Mister Transmission says,

“We’re the specialists, transmissions are all we do.”

 

If you are experiencing a problem with your vehicle’s transmission, please contact your local Mister Transmission and book an appointment for our FREE 21-Point Multi-Check Inspection.

For a more in-depth explanation, please visit our Transmission School

Vous aimeriez apprendre advantage?
Visitez un de nos emplacements!

image-reviews image-reviews
Customer Reviews
Great people -- great service!
Rob Dagenais
Great people -- great service!
Date: May 13, 2024
Website: Google
Good people got my transmission...
Isidro Thiessen
Good people got my transmission repaired quickly. It was expensive tho.
Date: May 12, 2024
Website: Google
Knowledgeable, professional and good service.
Jacobo Pineda
Knowledgeable, professional and good service.
Date: May 12, 2024
Website: Google
I had my 2007 Toyota...
Theresa F
I had my 2007 Toyota Rav 4 transmission rebuilt almost 2 years ago. Decided to bring it back for a transmission fluid change and for another check before the warranty expires. What I didn’t tell them is that there’s already a leak (my neighbour told me). I’m giving this business a 5 star review because they are honest. They told me it had a leak and they had to replace the seal, and it was still under warranty. Wow! Thank you!!!
Date: May 11, 2024
Website: Google
I have a 2015 Mazda...
Jaimin Patel
I have a 2015 Mazda 3 with automatic transmission. It is having jerking issue at 2nd gear when the car is cold. One of my known mechanic suggested Ken for transmission issues. I went there and parked my car overnight to make sure it is cold. In morning, Ken drove it and figure out instantly it was a computer mechanism trying to save fuel by engaging clutch and gear differently, which is normal and I should not spend any money on it. I liked Ken's experience and knowledge and his guidance which saved me going broke.
Date: May 11, 2024
Website: Google
Great friendly, prompt and reasonably...
Dey Muller
Great friendly, prompt and reasonably price service!
Date: May 10, 2024
Website: Google
Excellent experience. Jason is the...
Phil Wall
Excellent experience. Jason is the frontman. Super professional, friendly, and knowledgeable. Great service.
Date: May 10, 2024
Website: Google
Peter and his team did...
Peter Cadieux
Peter and his team did a great job! Very fair pricing and quick turnaround!
Date: May 10, 2024
Website: Google
Had a leak from the...
Bobros1944 Roz
Had a leak from the pan and front seal on my transmission. Despite being busy these guys were able to seal up the pan within one day. No leaks from the pan. I decided to hold off on the main seal as it is a slow leak and I'll deal with it in the winter when the cars in storage. Thanks
Date: May 9, 2024
Website: Google
Absolutely amazing service and help....
Tyrel &
Absolutely amazing service and help. Our shop was in a pickle with a customers vehicle. They got it remedied that day and gave us very valuable insight going forward. Thank you very much again! Greatly appreciated 🙏
Date: May 9, 2024
Website: Google
Featured Services
Transmission Repair

The evolution of transmissions has made these machines and systems increasingly complex. When transmission repairs are required, determining the cause and cure for what ails can be tricky.

Read More
Transmission Technology

At Mister Transmission we have access to leading-edge diagnostic equipment, enabling us to offer you the fastest and most accurate findings about what’s going on inside your vehicle’s transmission.

Read More
Transmission Maintenance & Service

Just as you have other parts of your car serviced, your transmission needs maintenance to ensure a long life and avoid transmission problems.

Read More
Mister Transmission Blogs
Recent Blogs
Transmission Shift Kits: Transforming Yo...
In the world of automotive enhancements, few upgrades can match the impact of a
Read More
May 7, 2024
Transmission Problems: Signs, Solutions,...
Maintaining a healthy transmission is crucial for the longevity and performance of
Read More
April 30, 2024
Saving On Your Ford Transmission Replace...
When it comes to maintaining your Ford, understanding the intricacies of transmission
Read More
April 22, 2024
5 Signs It’s Time For A Transmissi...
Maintaining your vehicle's transmission is crucial for its longevity and performance.
Read More
April 12, 2024
Prevent Automatic Transmission Slipping:...
Automatic transmission slipping is more than just an inconvenience; it can signal
Read More
April 5, 2024
CVT Transmission Repair Simplified: Expe...
Continuously Variable Transmissions (CVT) are known for their smooth, seamless
Read More
March 29, 2024
The Essential Guide To Cooling Transmiss...
For any vehicle, the health of its transmission system is paramount. One key aspect
Read More
March 22, 2024
The Role Of Solenoids In Your Transmissi...
In the intricate world of automotive transmissions, solenoids are fundamental
Read More
March 14, 2024
Transmission Shop Near Me: Ensuring Your...
When it comes to vehicle maintenance, the transmission is a critical component,
Read More
March 7, 2024
How A Timely Transmission Fluid Change C...
In the world of automotive maintenance, the importance of a timely transmission fluid
Read More
February 23, 2024