Ask the Car Doctor

YOUR TRANSMISSION

What is it?
The transmission works with the engine to provide power to you car’s wheels. Whether automatic or manual, the transmission plays a major role in the overall performance of your car. Make sure to check it at the first sign of problems.

What does it do?

A transmission/transaxle keeps the engine’s output optimally matched to the speed and load conditions. The torque converter, connected to the automatic transmission/transaxle input shaft, connects, multiplies and interrupts the flow of engine torque into the transmission. Universal and/or Constant Velocity (CV) joints connect to the driveshaft to transmit output power from the transmission to the rear axle on rear-wheel-drive cars and the front axle on front-wheel-drive cars. These joints also allow the driveshaft and/or CV shaft to work at an angle. The several different types of automatic transmission fluid serve multiple purposes: cleans, cools, lubricates, transmits force, transmits pressure, inhibits varnish buildup and continually protects the transmission.

Typical Wear and Tear
Wear and tear on the transmission can be influenced by:

  • Driving habits
  • Towing or excessive loads
  • Operating conditions
  • Condition of the transmission fluid
  • Frequency of regular maintenance

Symptoms

  • Slipping
  • Hesitation
  • Bucking
  • Grinding gears
  • Difficulty shifting

STEERING AND SUSPENSION

What is it?

The steering and suspension systems are key safety-related systems that largely determine your car’s ride and handling. Have these systems checked regularly, at least once a year and usually with a wheel alignment.

What does it do?
The suspension maintains the relationship between the wheels and the frame or unibody. The suspension system interacts with the steering system to provide vehicle control. When working properly, the suspension system helps absorb the energy from road irregularities such as potholes and helps to maintain vehicle stability. The steering system transmits your input from the steering wheel to the steering gear and other steering components to control the car’s direction.

Typical Wear and Tear
Over time, steering and suspension components wear out and require replacement. Regular checks are critical to maintain a safe car. Factors that affect wear include:

  • Driving habits
  • Operating conditions (potholes in road)
  • Vehicle type
  • Type of steering and suspension system
  • Frequency of regular maintenance such as chassis lubrication and wheel alignment

Symptoms

  • Car pulls to one side
  • Uneven tire wear
  • Excessive noise, vibration or bouncing
  • Loss of control

STARTING, CHARGING AND BATTERIES

What is it?
Your car’s starting and charging systems, and the battery, help ensure dependable vehicle operation whenever you drive your car and in all sorts of driving conditions. Make sure to check these systems regularly.

What does it do?
The battery stores electrical energy and the starter converts that energy into mechanical force to turn the engine for starting. The alternator produces electric current to replace what the starter used during start-up and to support electrical loads when the engine is running. An ignition module turns the low-voltage supply to the ignition coil on and off, and the coil produces the high voltage for the ignition system. This creates a spark at the spark plugs and ignites the air/fuel mixture in the engine. A belt transmits power from the front of the engine to the alternator’s pulley, along with other accessories.

Typical Wear and Tear
Driving habits such as frequent engine on/off cycles will cause more wear on the starter than a simple trip back and forth to work. Other factors include:

  • Driving and weather conditions
  • Mileage
  • Vehicle age
  • Excessive electrical draws like in-vehicle entertainment systems

Symptoms

  • Headlights and interior lights dim
  • “Check Engine” and/or battery light may come on
  • Accessories fail to operate

LIGHTING AND WIPERS

What is it?
Lights and wipers play a major role in safe driving – the chances for accidents increase if you can’t see or be seen. Some states have laws that require the headlights to be on with the wipers. If you detect any problems with your car’s lights or wipers, have them checked out at once.

What does it do?
The wiper system keeps excessive water, snow or dirt from building up on the windshield and removes them to maintain clear visibility through the windshield. The lighting system provides nighttime visibility, signals and alerts other drivers, and supplies light for viewing instruments and the vehicle’s interior.

Typical Wear and Tear
Lights and wipers are normal wear items that require periodic replacement. Factors affecting replacement intervals include:

  • Operating conditions (winter conditions are tough on wiper blades)
  • Frequency of use
  • Material and type of lights and wipers
  • Sunny weather – wiper blades can deteriorate faster and need more frequent replacement in desert states