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.

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Customer Reviews
Best customer service and quick...
Cyndie Moore
Best customer service and quick response time. Had my car back on the road in 3 business days. Ashley is the BEST, she kept me updated on the progress.
Date: March 18, 2024
Website: Google
Excellent service. Brian and other...
Navjot Kaur
Excellent service. Brian and other team members were very helpful. They gave honest advice for my vehicle and I can’t thank them enough for saving my thousands of dollars on repair.
Date: March 16, 2024
Website: Google
Excellent help! Chris had his...
Steve Vandevelde
Excellent help! Chris had his guys test and inspect my transmission for free. Knowing that I preferred to save money by doing as much as possible myself, they gave me all sorts of advice, laying out the pros and cons for my choice. I trust these guys. I recommend this shop.
Date: March 15, 2024
Website: Google
Jamie and the staff went...
DARIN GEAKE
Jamie and the staff went above and beyond to help me get my car fixed. I have a Subaru that was having issues and they spent a lot of time making sure everything was done correctly. Even though they did extra work and got extra parts to make it work, he stuck to his original quote (which btw was almost half of what I was quoted by a different shop). I would recommend Mr. Transmission to anyone!!!
Date: March 15, 2024
Website: Google
Mark and his staff are...
Ryan Rose
Mark and his staff are the BEST!!! Kind, knowledgeable, transparent. Will gladly take any and all of my future business to him and his exceptional team.
Date: March 15, 2024
Website: Google
Amazing customer service! Super friendly!...
Cynicalest T
Amazing customer service! Super friendly! Family owned by mark and son both awesome people!
Date: March 15, 2024
Website: Google
Thank you for the great...
Linda Jones
Thank you for the great service we received at Mister Transmission in Barrie. It was exceptional. They made sure the vehicle was at 100% before they let us pick it up. I would recommend them to anyone that needs transmission repairs. All the employees were pleasant and made you feel important. If you had any questions they answered them right away. Great job everyone. Ted and Linda Jones.
Date: March 14, 2024
Website: Google
Friendly and efficient, you couldn’t...
Dale Allen
Friendly and efficient, you couldn’t ask for much more from a mechanic.
Date: March 14, 2024
Website: Google
Got my car back fast...
Brenda Kane
Got my car back fast , amazing staff. Thanks Mr transmission!!
Date: March 14, 2024
Website: Google
I needed an expensive repair...
Daniel Zwiercan
I needed an expensive repair but the folks at Mister Transmission helped me save money where I could and did a great job. Thank you.
Date: March 14, 2024
Website: Google
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