The Automotive Lift Repair Orlando drivetrain consists of various components that transfer power from the engine to the wheels. When combined with the engine, it is referred to as the “powertrain.” For a refresher on how the internal combustion engine converts chemical energy into rotational energy, refer to Lesson 5. The drivetrain primarily includes the transmission, the drive line (or drive shaft), and the rear differential.
The Automotive Lift Repair Orlando crankshaft’s rotation in an internal combustion engine does not directly translate to wheel rotation. Similar to a bicycle, motor vehicles use gears; lower gears are for slower speeds and higher gears for faster speeds. Despite the RPM reading on the dashboard tachometer being relatively constant or within a range, the transmission adjusts the input speed from the crankshaft to the output speed by changing gear ratios. For example, in first gear, a 4:1 ratio means the input shaft turns four times for every one turn of the output shaft, resulting in 1,000 RPMs at the output if the input is 4,000 RPMs. Subsequent gears have different ratios, with fourth gear often being a direct drive at a 1:1 ratio.
Think of a bicycle’s sprockets: the large front sprocket turns as you pedal, and it connects to varying-sized rear sprockets through a chain. Changing gears adjusts the mechanical advantage for pedaling.
In direct drive, the input and output speeds are identical with no gear reduction. Modern vehicles feature overdrive, a ratio of 0.75:1, where the input speed is lower than the output speed, improving fuel efficiency.
These examples illustrate the general concept, but each vehicle has its own specific input-to-output ratios.
The Automotive Lift Repair Orlando drive line or drive shaft is a cylindrical component that transmits power from the transmission to the rear differential, positioned longitudinally under the vehicle.
The rear differential uses Automotive Lift Repair Orlando hypoid gears to redirect the drive shaft’s rotation by 90 degrees to turn the axles and rear wheels. Inside the differential, spider gears allow the wheels to rotate at different speeds while turning. For instance, in a right turn, the driver’s side rear wheel covers a greater distance than the passenger side rear wheel, similar to how a protractor’s legs function—one leg pivots while the other traces a circle. While rear wheels don’t turn as sharply as a protractor, the concept remains the same: the inner wheel travels a shorter distance.
Manual vs. Automatic Transmission:
An Automotive Lift Repair Orlando manual transmission, also known as a standard transmission, operates with conventional gears. These gears are constantly engaged when the engine is running and the clutch pedal is released. To change gears, the driver manually selects a gear using the gear shift, which connects the chosen gear to the output shaft. To shift to another gear, the clutch is depressed, and the new gear is selected, attaching it to the output shaft.
In contrast, an automatic transmission employs “sun and planet” gears. This system features a central “sun” gear surrounded by “planetary” gears (typically three or four). These gears can rotate, shift, or lock to create various speeds and directions. Gear changes in an automatic transmission are controlled by hydraulic clutch packs and/or bands managed by a valve body.
Types of Automatic Transmission Fluid:
There are over 30 different types of Automotive Lift Repair Orlando transmission fluid for modern vehicles, though they may appear similar. Always consult the owner’s manual to select the correct fluid. Aftermarket fluids may be compatible with multiple vehicles, but ensure that the fluid specified in the manual is listed on the aftermarket product label.
Lubricants for Standard Transmissions:
Modern standard (manual) transmissions use various types of fluids. Ensure that any fluid used meets the manufacturer’s specifications.
Lubricants for Differentials:
Differentials typically use conventional 80-90 gear oil, with the numbers indicating the oil’s weight and viscosity. Some vehicles might require special fluids. Always check that the fluid complies with the manufacturer’s specifications. Limited slip differentials may need an additional additive.
Front Wheel Drive, Rear Wheel Drive, and Four Wheel Drive:
The key differences among front wheel drive, rear wheel drive, and four wheel drive lie in the drivetrain configuration and how Automotive Lift Repair Orlando power is transmitted.
– Front Wheel Drive (FWD): Combines the differential and transmission into a single unit known as a transaxle, which transmits power from the engine to the front wheels.
– Rear Wheel Drive (RWD): Transmits power from the engine through the transmission to the drive shaft, which then delivers power to the rear differential.
– Four Wheel Drive (4WD): Distributes power through the transmission to a transfer case, which then sends power to both front and rear drive shafts and differentials.
Brakes are crucial for slowing a vehicle’s momentum, enhancing control, and ensuring road safety. The brake system operates on hydraulic principles to apply force to friction material, which generates heat. As a vehicle moves, it has kinetic energy, which brakes convert into heat energy.
There are two main types of brakes: disc brakes and drum brakes. The primary differences between them are their shapes and the types of friction materials used. Friction material acts as a buffer to prevent metal-on-metal contact when braking. It can handle the heat produced during braking but needs regular replacement throughout the vehicle’s life.
– Disc Brakes: These brakes feature a rotor (or disc) at each wheel, with brake pads serving as the friction material. When the brake caliper applies force, the brake pad presses against the rotor, generating heat and slowing the vehicle.
– Drum Brakes: Shaped like a drum, these brakes use brake shoes as the friction material. A wheel cylinder pushes the brake shoes, which have a friction lining, against the drum. The hydraulic mechanism expands the shoes to press against the drum, generating heat and stopping the vehicle.
The master cylinder is a hydraulic component that provides force to the brake calipers and/or wheel cylinders. The wheel cylinders (for drum brakes) and brake calipers (for disc brakes) are both referred to as “hydraulic slave cylinders,” following standard industry terminology.