As your transmission repair shop in Mesa we feel it is our duty to not just fix cars, but to educate our customers about how some of the parts of a motor vehicle work. First, off, let’s cover the parts of an automatic transmission.
What Are the Parts of an Automatic Transmission?

Your transmission has a lot of parts, but there are four main parts of any automatic. These parts are:
the bell housing, the gears, the fluid, and the filter. A lot of people don’t look under their car, but this is where you can find your bell housing, right behind your engine on the underside of your car if you have a rear-wheel drive vehicle. If you’ve got a front-wheel drive car, your bell housing will be stuck on the side of the engine under the hood. Your transmission’s gears are divided into planetary gears and main gears.
If you don’t know what you’re doing, we don’t recommend that you take apart your transmission to see the difference between main gears and planetary gears. There are dozens of gears in a modern automatic transmission and it takes just one broken one to cause a problem. Now, let’s go on to the last two components of a transmission.
Transmission Fluid and Filters
Transmission fluid is literally the lifeblood of an automatic, and as such, the fluid is a bright red color. If you see a leak in your driveway under where you normally park your car, and it is red, it is most likely transmission fluid. Like a lot of your car’s fluids, there is also a transmission filter for your transmission’s fluids. Why do you need one? Well, the dirtier the fluid the more likely it is to cause a gear to go bad or lock up your transmission.
So remember, while your transmission is a lot of parts combined into a whole, if your mechanic ever tries to tell you about any part that we’re not covering here, be sure to ask a lot of questions. And if you’re encountering difficulty with your car, don’t just take your vehicle into a mechanic, take it into a shop that specializes in transmission repair.
Our next article will cover symptoms of transmission problems.
Trail Transmission
11240 East Apache Trail
Apache Junction, AZ 85120-3529
(480) 986-7367
https://trailtransmission.com/