Transmission Basics: Understanding the Basic Parts

By Mister Transmission

Before you hand over the keys, brush up on the basics of automatic transmissions so you can understand why your transmission is acting up. Here we’ll cover the basic parts of a transmission, basic transmission problems and how to know if a rebuild is in your future.

What is a Transmission?

The transmission allows you to shift your car from gear to gear, knowing how fast you need to go and how quickly you need to get there. Remarkable stuff.

Parts of a Transmission: 101

While there are many little parts inside, your transmission is essentially made up of 4 key parts of systems:

Bell Housing: This is the cone shaped metal case that you can see when you peek underneath your car. If you have a front-wheel-drive car it’s stuck on the side of the engine under the hood. If your car is rear-wheel-drive, the transmission will be mounted underneath the car behind the engine.

Gears: Even though you’re not shifting them, an automatic transmission has gears. They are broken into main gears and planetary gears. You need all of these to be able to drive.

Fluid: Transmission fluid is very important to an automatic transmission. All of the magic happens in the fluid. Most cars come with red transmission fluid, good to know if you are looking for a leak.

Filter: All of that fluid has to be clean for your car to shift gears at the right time. To keep things fresh, your transmission has a filter to catch any gunk.

Transmission Problems: 101

If your car won’t start or doesn’t run smoothly, these problems are caused by the same faults in your transmission, so whichever your car is doing, the following applies:

Is your fluid level correct?

It’s important to check your transmission fluid at least twice a year. Not only can a low fluid level cause your car to shift poorly, it can eventually lead to transmission damage, and a costly repair. If your car seems to be losing fluid on a regular basis, you may have a leak.

Is your transmission leaking?

Checking for leaks isn’t as difficult as it may seem. The transmission is a closed system, so there are only a few places that can spring a leak. Unless it’s been changed to a non-dyed fluid, your car will have red transmission fluid. Here are a few places to check for leaks:

  • At the filler tube base.
  • At the drain hole underneath the transmission.
  • Between the transmission and the engine.
  • At the selector shaft – the rod that connects your gear shift to the transmission.
  • At the speed sensor mounting point: This will either be your cable screwing into the transmission housing or an electronic sensor bolted to the housing.
  • In the radiator: If your car has a transmission cooler, it’s possible that a leak will cause transmission fluid to leak into the radiator fluid. They don’t mix well, so you’ll see it floating around in there.

Is Your Filter Clogged?

Your transmission’s filter is vital to its performance. If you haven’t replaced your filter in a while, or ever, be sure to do this before you start talking about rebuilds or replacements.

Time for a Rebuild?

When your transmission is worn out, you’ll have to have it rebuilt. For some makes and models of car this is true a little too often. The important thing is checking any other possible causes to your problem before you have it taken apart. If you haven’t replaced your filter yet, start there as this fixes a good percentage of transmission problems. If your filter is in good condition and nothing simple is out of adjustment, it’s likely you’ll need a rebuild. The good news is that at Mister Transmission we offer a rebuild warrantee so you’ll know it will get fixed and stay fixed.

Generally, transmission problems can’t be fixed by the average do-it-yourselfer. There are just too many specialized and expensive tools and pieces of equipment needed. We recommend keeping up with your regular maintenance to keep you out of the shop as much as possible.

Want to know more?
Visit one of our locations

image-reviews image-reviews
Customer Reviews
rich is a good guy
Matt Adam
rich is a good guy
Date: December 1, 2020
Website: Google
Although it was a minor...
Mario Iacobucci
Although it was a minor repair that some unnamed business botched horribly, this shop was very fair in price and took me in immediately. Thanks
Date: December 1, 2020
Website: Google
My Caravan transmission was giving...
Aaron Dias
My Caravan transmission was giving a lot of problems and took it to Mr. Transmission, and got it fixed. Thanks to Denise and Sean for their amazing customer service.
Date: November 30, 2020
Website: Google
Very good customer service.
Irfan Sheikh
Very good customer service.
Date: November 30, 2020
Website: Google
I was happy with the...
Evan Gobeil
I was happy with the help I received when my car broke down on the side of the road. They were able to get me in right away and provided me with an explanation of what happened and what was done. I would recommend to anyone needing work done on their vehicle.
Date: November 30, 2020
Website: Google
Steve and his team are...
Anne Marie
Steve and his team are great.As a woman, I have been taken to the cleaners before by a garage.What a refreshing change 🙂 These guys are honest, respectful, knowledgeable and treat customers with respect. You can go there knowing you will not get ripped off. They do what is necessary.Recommend these guys 💯%.
Date: November 30, 2020
Website: Google
Very friendly and professional.
RodzillaRoar
Very friendly and professional.
Date: November 28, 2020
Website: Google
MMMMMMMMMM SATWAN NUMBA WAN- Brent
You Know
MMMMMMMMMM SATWAN NUMBA WAN- Brent
Date: November 28, 2020
Website: Google
Very friendly and professional.
RodzillaRoar
Very friendly and professional.
Date: November 28, 2020
Website: Google
Bob Monday is very knowledgeable...
Mike Graham
Bob Monday is very knowledgeable and honest. I feel the repairs he did on my vehicle were what he would do on his own.
Date: November 28, 2020
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
Recent Blogs
FAQs About The Torque Converter
Torque converters are key components of transmissions. How often do they require
Read More
November 30, 2020
5 Tips For Transmission Maintenance
Good transmission maintenance practices mean the difference between years of
Read More
November 25, 2020
Are CVT Transmission’s Difficult T...
You’ve heard of automatic transmissions. You’ve heard of manual transmissions.
Read More
November 18, 2020
How To fix A Slipping Transmission
What is the fix for a slipping transmission? It’s simple. Just pop the hood of your
Read More
November 12, 2020
What Are The Indications Of A Bad Torque...
The torque converter is an integral part of the transmission. However, torque
Read More
October 19, 2020
“What Transmission Do I Have?̶...
On this site you will see terms like “transmission overhaul”, “solenoid
Read More
October 5, 2020
How Do You Rebuild A Transmission?
The decision to rebuild a transmission is not to be taken lightly. While a
Read More
September 30, 2020
4 Things A Transmission Shop Can Do For ...
Transmission shops look after your transmission to ensure it runs as efficiently and
Read More
August 28, 2020
How Can You Tell Transmission Problems A...
The first step in solving any problem is to correctly identify its cause. The same is
Read More
August 21, 2020
What Are The Most Common Transmission Re...
Transmissions are incredibly intricate pieces of machinery. There’s a lot that goes
Read More
August 14, 2020