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Summary
  • A car transmission usually looks like a bell, although it sometimes has a boxy shape.
  • The transmission transfers engine power to the axle and enables changing the gear ratio to drive at different speeds.
  • It is recommended to hire a professional to remove the transmission if you need to. The job is not usually something DIYers can do.

Q: What does a car transmission look like?

A: The typical car transmission resembles a church bell. Its rear end is wider than its front end. Because of its tapering shape, the transmission casing is sometimes called a bell casing. Some transmission casings are shaped like boxes.

The transmission transfers power from the engine through the final drive, which includes the differential, and that drives the axles that drive the wheels.

Furthermore, it provides the torque that gets the car moving and then changes the gear ratio between the engine and wheels as the vehicle picks up speed to keep the engine operating at the most fuel efficient and power producing point at all times.

car transmission diagram
Cutaway model of a car transmission | Image Source: Richard McCuistian

This photo is a cutaway model of a Ford AOD rear-wheel-drive automatic transmission. The torque converter with its internal parts color coded is visible as a cutaway component on the right end of the photo.

Rear-wheel-drive transmissions bolt to the engine and transmit torque through a driveshaft to the final drive in the rear axle.

front wheel drive transmission diagram
Front wheel drive transmissions (see photo) also bolt to the engine but are built to include the final drive as part of the unit (see large blue gear at bottom of photo) but they also bolt to the engine. These come in various configurations, but this is a Ford ATX automatic transaxle. | Image Source: Richard McCuistian

Torque is transmitted to the transmission input shaft by way of the torque converter on an automatic transmission or transaxle and by the manual clutch and pressure plate on a manual shift transmission.

Manual transmissions require the driver to manually operate the clutch and shift gears. Automatic transmissions do the job for drivers.

Manual transmissions typically have two shafts. On rear-wheel-drive manual transmissions, there’s a main that consists of the input and output shafts (two different parts), and the countershaft or cluster gear that provides the power path for the gears on the mainshaft to transmit torque from the input shaft to the output shaft in every gear except the direct drive gear, which locks the input and output shafts together as one.

gears inside rear wheel drive manual transmission diagram
Diagram showing gears inside a rear-wheel-drive manual transmission | Image Source: Richard McCuistian

The illustration is a diagram of the gears inside a rear-wheel-drive manual transmission and it shows fifth gear powerflow as directed through the cluster gear from the input shaft to the output shaft. Front-wheel-drive manual transaxles work in a similar fashion but usually have three shafts instead of two with the output directly driving the pinion gear that spins the ring gear and differential.

Tips on How to Access the Car Transmission

Before you can access the transmission, you need to know where the part is. Fortunately, it’s usually behind the engine. Of course, the engine’s position changes depending on the car’s powertrain.

, What Does a Car Transmission Look Like?

Pro Tips are nuggets of information direct from ASE-certified automobile technicians working with CarParts.com, which may include unique, personal insights based on their years of experience working in the automotive industry. These can help you make more informed decisions about your car.

Pro Tip: If you don’t know how to remove the transmission and you don’t have the tools, hire somebody else to do it. It can be extremely difficult and dangerous for the inexperienced DIY person.

You need heavy-duty jacks to raise your car high enough that you can access the transmission from under the vehicle. Furthermore, you need a transmission jack to lower the transmission safely. Move the transmission jack under the raised car, position it below the transmission, and raise the jack. Detach the transmission, allowing it to rest on the jack. Then lower the transmission jack and move it out from under your car so that you can work on the transmission.

About The Authors
Written By Automotive and Tech Writers

The CarParts.com Research Team is composed of experienced automotive and tech writers working with (ASE)-certified automobile technicians and automotive journalists to bring up-to-date, helpful information to car owners in the US. Guided by CarParts.com's thorough editorial process, our team strives to produce guides and resources DIYers and casual car owners can trust.

Reviewed By Technical Reviewer at CarParts.com

Richard McCuistian has worked for nearly 50 years in the automotive field as a professional technician, an instructor, and a freelance automotive writer for Motor Age, ACtion magazine, Power Stroke Registry, and others. Richard is ASE certified for more than 30 years in 10 categories, including L1 Advanced Engine Performance and Light Vehicle Diesel.

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic. The accuracy and timeliness of the information may change from the time of publication.

File Under : Transmission , Auto Repair , DIY Tagged With :
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