Clutch:

Higher or lower pedal
Grinding between gears
Motor races without "pulling"


Exhaust Systems:

Rattles, smells or loudness


Cooling Systems:

Idle changes
Fluid leaks
Lukewarm air conditioning


Belts:

Squeeking or signs of crackage


Brakes:

Pulsation
Constantsqueeking or grinding
Low or seeping, low brake pedal
Brake fluid leaks


It happens to all of us: while driving we suddenly think, "What does that noise mean?" Here is a list of possible symptoms and recommended maintenance schedules to keep in mind:

10,000 - 15,000 miles:

Inspect brakes
Rotate tires
Replace air filter & wipers blades
Test antifreeze


30,000 miles:

Inspect & Replace fuel filter
Replace antifreeze
Test & Flush transmission (or every 15,000 miles if you use your vehicle for hauling)


40,000 - 50,000 miles:

Inspect brakes, belts, exhaust, hoses and power steering
Replace tires


70,000 - 80,000 miles:

Replace plug wires and spark plugs
Watch for fluid leaks
Lukewarm air conditioning