Carautonomy — car parts and warning lights explained
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Drivetrain

What is a Gearbox / Transmission?

Lets the engine spin at its happy speed at any road speed.

Different cogs = different speeds for the wheels

Simplified animation — not to scale.

In plain English

A box of gears (manual, automatic, dual-clutch or CVT) sitting between the engine and the wheels. Different gear ratios let the engine work efficiently at any speed.

A simple analogy

"It is the bicycle gears of the car — pick the easy gear up hills and the fast gear when cruising so your legs (engine) don't get exhausted."

How it works

You (or the car) select a gear. Inside the box, pairs of cogs mesh to change the ratio between the engine and the wheels: low gears for pulling away, high gears for cruising.

Signs of trouble

  • Crunching or grinding when changing gear
  • Slipping out of gear or refusing to engage
  • Whining, humming or clunking noises
  • Burning smell or transmission fluid leaks
  • Jerky or delayed automatic shifts
Rough UK cost

£800–£4,000+

Parts: £400–£3,000+ (rebuilt or used)
Labour: £400–£1,200

Always get a written quote. Prices vary by car, region, and parts brand.

Heads up: Carautonomy is for general guidance only. If your car is showing warning lights or behaving oddly, get it looked at by a qualified mechanic.

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