A transmission is a machine in a power transmission system, which provides controlled application of power. Often the term 5-speed transmission refers simply to the gearbox, that uses gears and gear trains to provide speed and torque block conversions from a rotating power source to another device.
A transmission casing houses all the parts of the transmission. It sort of looks like a bell, so you’ll often hear it referred to as a “bell casing.” The transmission casing is typically made of aluminum.
Besides protecting all the moving gears of the transmission, the bell casing
on modern cars has various sensors that track input rotational speed from
the engine and output rotational speed to the rest of the car.
Ever wonder why you can turn on your car’s engine, but not have the thing move forward? Well, that’s because power flow from the engine to the transmission is disconnected. This disconnection allows the engine to continue running even though the rest of the car’s drivetrain isn’t getting any power.
The torque converter sits between the engine and the transmission. It’s a donut looking thing that sits inside the big opening of the transmission’s bell case. It has two primary functions in terms of transmitting torque:
1. Transfers power from the engine to the transmission input shaft
2. Multiplies engine torque output
There are four parts inside the torque converter-
1. Pump (aka impeller)
2. Turbine.
3. Stator (aka Reactor).
4. Torque converter clutch.
As your vehicle reaches higher speeds, it needs less torque to keep the car going. Transmissions can increase or decrease the amount of torque sent to the car’s wheels thanks to gear ratios. The lower a gear ratio is, the more torque is delivered. The higher a gear ratio is, the less torque is delivered.
Brake bands are made of metal lined with organic friction material. The brake bands can tighten to hold the ring or sun gear stationary or loosen to let them spin. Whether a brake band tightens or loosens is controlled by a hydraulic system.
A transfer case is a specialized component that is used on four-wheel drive and all-wheel drive vehicles. It is essential on vehicles that use both front and rear axles to drive. And in the case of 4x4s, each of the four wheels need to be powered.
Transfer case parts-
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