Transmissions Flashcards
What happens if a synchromesh unit is reassembled without matching alignment marks?
It may cause difficult gear shifting or premature wear.
In a three-speed manual transmission, which gear bypasses the countershaft?
High gear (direct drive).
What happens when a clutch disc is installed backward?
It can cause improper engagement and shifting issues.
What is the purpose of a pilot bearing/bushing?
Supports the input shaft and allows it to rotate independently from the crankshaft.
How does a synchronizer work?
It uses friction to match gear speeds before engagement.
What component allows the driveshaft to flex with suspension movement?
Universal joints (U-joints).
What is a common symptom of a failing U-joint?
Clunking or vibration, especially when accelerating or decelerating.
What is the difference between a constant velocity (CV) joint and a U-joint?
A CV joint provides smooth power transfer at various angles, while a U-joint has speed fluctuations at extreme angles.
What is driveshaft phasing?
Proper alignment of U-joints to prevent vibrations.
What is the purpose of the torque converter in an automatic transmission?
It allows smooth engagement of power and multiplies torque.
What are the three main components of a torque converter?
Impeller, turbine, and stator.
What is the function of an automatic transmission valve body?
It directs hydraulic fluid to engage the correct gears.
What does ‘slipping’ in an automatic transmission indicate?
Worn clutches, low fluid level, or a failing torque converter.
What is the function of a limited-slip differential (LSD)?
It prevents excessive wheel spin by transferring power to the wheel with more traction.
What can cause excessive play in a differential?
Worn side gears, pinion bearings, or excessive backlash.
What happens if backlash is too tight?
Gears can overheat and wear prematurely.
What is the purpose of pinion bearing preload?
It minimizes bearing clearance to reduce wear and noise.
What does the input shaft do?
Transfers power from the engine to the transmission.
What does the countershaft do?
Holds gears that transmit motion to the output shaft.
What does the output shaft do?
Transfers power to the driveshaft.
What do synchronizers do?
Match gear speeds for smooth shifting.
What are shift forks and linkages used for?
Moving gears into engagement.
How does the reverse gear work?
Uses an idler gear to reverse rotation direction.
What is the purpose of a friction clutch?
To connect or disconnect power flow from the engine to the transmission.
