The silent car habit that damages automatic gearboxes in city traffic, mechanics say

Rush hour, dual carriageway, drizzle on the windscreen. The cars ahead concertina in slow motion, each one edging half a bonnet length at a time. Your automatic sits in Drive, foot hovering between brake and accelerator, cabin quiet apart from the tick of the indicator and the murmur of the radio.

You nudge the throttle, roll forward a metre, then squeeze the brake. Off, on. Off, on. The whole queue shuffles like a restless caterpillar, never quite stopping, never properly moving. It feels smoother, more “attentive” than leaving a gap and coasting.

Mechanics say this calm, polite creeping is one of the quietest ways to cook an automatic gearbox in city traffic. No screeching tyres, no drama – just steady heat and wear every time you feather the pedal.

The calm-looking habit that cooks your gearbox

The habit looks harmless: in stop‑start traffic you keep the car inching forward, matching every tiny movement of the vehicle in front. You rarely sit fully still. Instead, you “ride the creep” – micro‑accelerating, then braking, over and over.

In a traditional automatic, that means the torque converter sits in its worst operating window for minutes at a time. In many dual‑clutch automatics, it means the clutches are slipping constantly, mimicking a human riding the clutch in a manual. From the driver’s seat it feels gentle; inside the transmission it is anything but.

City driving makes it worse. Short journeys, cold starts and endless queues give the gearbox little time to cool or circulate fresh fluid. Do it every weekday, and that quiet shuffle becomes a daily stress test for parts you never see.

What constant creeping does inside the transmission

At very low speeds in Drive, most autos rely on controlled slip. The engine turns faster than the road wheels, and the difference is soaked up as heat in fluid or friction material.

• In a torque‑converter automatic, that slip churns the transmission fluid, building heat. Hot fluid thins, loses protection, and can leave varnish on internal parts.
• In a dual‑clutch auto, the clutches bite and release repeatedly at low speed. Each gentle crawl forward is a tiny wear event on a very expensive component.

On a clear dual carriageway, the gearbox can lock up and run efficiently. In a crawling city queue outside a retail park, it often never gets there. Instead it lives between 0 and 10 mph, the zone with the most slip and the least airflow.

Early signs are easy to shrug off: a slight shudder when you pull away, a delay before Drive engages, a faint thump on upshifts when hot. By the time it becomes obvious, many motorists are looking at a four‑figure repair.

Habit in traffic	What it does inside	Long‑term risk
Constant tiny creeping	Keeps clutches/torque converter slipping	Overheating, accelerated wear
Holding on throttle on a slope	Uses drivetrain instead of brakes	Burnt fluid, damaged clutches
“Feather‑parking” for ages	Long periods of low‑speed slip	Judder, harsh shifts, early failure

How to move in queues without hurting an automatic

Protecting an auto in traffic does not mean driving like a saint. It means changing how you handle the slow bits.

• Build a buffer, then roll once. Leave a larger gap to the car in front. Let it open to a couple of car lengths, then roll smoothly to close it in one go. One gentle move is kinder than ten tiny shuffles.
• Come to a clean stop. Use the brake to stop firmly but smoothly, then keep your foot on it. Sitting still in Drive with your foot on the brake is usually fine; it creates less slip than constantly creeping.
• Use auto‑hold or the parking brake at long reds. If your car has an auto‑hold function, use it in queues and at lights. If not, a firm pull on the parking brake at a very long stop gives your foot – and the transmission – a breather.
• On hills, trust the brakes, not the throttle. Never “catch” the car on the accelerator to prevent it rolling back. Let the brakes hold it. On steep slopes, use hill‑start assist or the handbrake rather than balancing on the drivetrain.
• Be smooth with the first metre. The hardest work for the gearbox is pulling away. A steady squeeze on the throttle beats a jab‑and‑lift every time.

You still make the same progress through the queue. You just stop asking the gearbox to do the job of the brakes every few seconds.

Other quiet gearbox killers in town

Creeping is not the only low‑drama habit that shortens an automatic’s life.

• Clicking from Reverse to Drive while still rolling. Many drivers flick straight from R to D when parking before the car has fully stopped. The jolt you do not quite feel is being absorbed by internal components.
• Launching hard from cold. Pulling out briskly the moment you start the engine gives the gearbox little time to circulate and warm its fluid. In winter, those first few hundred metres matter.
• Living in “manual” mode at low speed. Forcing early downshifts around town to get more engine braking sounds clever. In reality, it can mean extra shifts and more clutch action in busy streets.

On their own, none of these is guaranteed to break a car. Combined with years of stop‑start creeping, they add up.

A simple city‑traffic checklist

Before the next crawl through the ring road or school run bottleneck, a few small changes go a long way:

• Leave space, then move in one smooth roll instead of inching constantly.
• Stop cleanly and hold the brake, rather than balancing on the throttle.
• Use auto‑hold or the parking brake at long lights and rail crossings.
• Let the car come to a complete stop before shifting between R and D.
• Drive gently for the first 5–10 minutes, especially in cold weather.
• Follow the service schedule for transmission fluid – even if the brochure once said “sealed for life”.

FAQ:

• Is it bad to sit in Drive with my foot on the brake at lights? In most modern automatics, no – it’s expected. Short stops in Drive with firm brake pressure create less wear than creeping constantly. For very long waits, auto‑hold or the parking brake can be more comfortable.
  
• Should I shift to Neutral in every queue to save the gearbox? Constantly flicking between D and N brings its own wear and can confuse some start/stop systems. Occasional use of Neutral on very long stops is fine, but it is not a cure‑all and offers little benefit in short queues.
  
• Do hybrids and EVs have the same creeping issue? Pure EVs do not have a traditional gearbox or torque converter, so the problem is different. Many hybrids still use gearsets and clutches that dislike endless low‑speed slip, so the same “avoid constant creeping” advice generally applies.
  
• My car brochure said the gearbox is ‘maintenance‑free’. Can creeping really matter that much? “Maintenance‑free” often means “will last the warranty period”. Mechanics regularly see high‑mileage city cars with tired automatics brought on faster by heavy stop‑start use and creeping habits. Smooth driving and timely fluid changes help close the gap between brochure promises and real life.