Four-seat Smart city car
A used Smart Forfour can be a practical urban car, but the two generations are mechanically unrelated and require different checks. The first Forfour is a front-engined Mitsubishi-based hatchback, while the later model uses a rear engine, rear-wheel drive and Renault-related components.
For most second-generation buyers, the naturally aspirated 1.0-litre petrol engine with a five-speed manual is the simplest option. The 0.9 turbo suits faster roads, twinamic provides smoother two-pedal driving than the older Softouch system, and the electric Forfour requires battery and charging checks instead of engine and clutch inspection.
Forfour buying choice: Identify the generation before comparing engines, gearboxes or repair costs. Choose a manual petrol model for straightforward city use and consider the turbo only when stronger performance is useful. Electric Drive and EQ versions suit predictable urban mileage with reliable access to AC charging.
What the Smart Forfour is and who it suits
The Smart Forfour was designed for buyers who liked the compact character of the Smart Fortwo city car but needed rear doors and additional seats. Both Forfour generations are short, upright hatchbacks, yet they share little beyond the name and their focus on urban driving.
The first-generation W454 was sold from 2004 to 2006. It has a front engine, front-wheel drive and a platform shared with the Mitsubishi Colt. Depending on the rear bench fitted, it could carry four or five people and offered more conventional small-hatchback practicality than the later model.
The second-generation W453 arrived in 2014 after a long production gap. Developed alongside the third-generation Renault Twingo, it places the engine beneath the rear luggage floor and drives the rear wheels. It has four seats, exceptionally wide-opening rear doors and a very tight turning circle suited to crowded streets.
W454 for conventional use
The first generation behaves like a normal front-wheel-drive hatchback and offers a broader choice of petrol, diesel and performance engines.
W453 for tight cities
The rear-engined second generation turns in a small space and provides excellent rear-door access, but only four seating positions.
EQ for electric commuting
The electric Forfour removes the petrol engine and gearbox but adds battery, charging and high-voltage inspection requirements.
First-generation Smart Forfour W454
The W454 was produced in the Netherlands alongside the Mitsubishi Colt and uses a conventional front-engine, front-wheel-drive layout. Petrol options included 1.1-, 1.3- and 1.5-litre engines, while a three-cylinder 1.5 CDI diesel was also offered. The BRABUS version used a turbocharged 1.5-litre petrol engine and must be assessed as a performance model.
The smaller 1.1 petrol is adequate for urban use, while the 1.3 and naturally aspirated 1.5 provide more useful performance with passengers. The diesel is better suited to regular longer journeys than repeated short trips. At the current age of these cars, cooling, oil consumption, ignition, injection and exhaust condition matter more than small differences in official fuel economy.
Most cars use a five-speed manual gearbox. Selected versions were available with six-speed Softouch Plus, an automated manual transmission that operates a conventional friction clutch electronically. It should not be confused with the twinamic dual-clutch gearbox used by the later W453.
The first-generation rear bench can slide to balance passenger space and luggage capacity, and some cars have a three-person rear seat. Test every adjustment and locking point. Also inspect the panoramic roof where fitted, air conditioning, central display, electric windows and folding front-seat functions.
Because W454 examples are now considerably older than the second generation, examine suspension joints, springs, steering, brake pipes, exhaust sections, sills and floor edges for age-related wear or corrosion. A low odometer reading does not compensate for long storage, old tyres or incomplete fluid servicing.
Practical note: The W454 and W453 are not two facelifts of the same car. Engine position, drive layout, transmissions, seating and service access are different, so repair advice and parts must be matched to the generation.
Second-generation Smart Forfour W453
The W453 shares its basic architecture with the Renault Twingo III. Its engine sits beneath a removable panel in the rear luggage area, while several service points are accessed beneath the panel at the front of the car. Check that both covers, their fasteners and the surrounding insulation remain complete.
The rear-engine layout gives the Forfour a small turning circle and leaves the front wheels free to steer through a large angle. Rear-wheel drive provides good urban traction, although tyres, alignment and electronic stability systems still need to be in sound condition.
The rear doors open unusually wide, which helps with child seats and loading. Depending on specification, the rear compartment may have a conventional split-folding bench or readyspace seats whose cushions fold down to create extra loading height. Operate every hinge and latch and confirm that the seats lock securely.
Boot capacity is restricted by the engine beneath the floor, and the load area may become warm after driving. Excessive heat, a burning smell, damaged insulation or an engine cover that does not sit correctly requires further inspection rather than being dismissed as a normal rear-engine characteristic.
The W453 received a styling and technology update before the range became electric-only. Equipment varies by trim and year, including climate control, heated seats, touchscreen navigation, reversing camera, lane assistance and forward-collision warning. Test the fitted systems individually.
Smart Forfour petrol engines and everyday suitability
1.0-litre naturally aspirated engine
The naturally aspirated three-cylinder 1.0 is the most straightforward W453 petrol engine. It suits short urban journeys and drivers who value simple power delivery over strong acceleration. The lower-output version can feel slow on faster roads, while the more widely available higher-output version is adequate for ordinary mixed driving.
A regular three-cylinder pulse and some vibration at idle can be normal. Persistent misfiring, difficult starting, a flashing engine warning or strong fuel smell is not. Ignition, intake, fuel and sensor faults can create similar symptoms, so use the check engine warning guide rather than assuming one component has failed.
0.9-litre turbo engine
The turbocharged 0.9 provides noticeably stronger mid-range performance and is better suited to regular faster-road use, hills or a fully occupied car. It also adds turbocharger, boost-control and additional intake components that need correct oil servicing and fault-free operation.
Power should build smoothly without hesitation, smoke or sudden reduced-power operation. Uneven boost does not prove that the turbocharger itself has failed; ignition, air leaks, control valves, fuel delivery and sensors can cause similar behaviour.
BRABUS version
The W453 BRABUS uses a more powerful version of the turbocharged engine together with twinamic, larger wheels and sportier chassis settings. Inspect tyres, wheel rims, brakes, suspension and modifications carefully. A louder exhaust or non-standard engine software is not evidence of better maintenance.
Choose 1.0 for simplicity
The naturally aspirated engine is suitable for gentle city use and removes the turbocharger and boost-control components found on the 0.9.
Choose 0.9 for faster roads
The turbo engine is more flexible outside town but should have clear oil history and smooth, warning-free boost delivery.
Manual, Softouch and twinamic gearbox behaviour
Five-speed manual
The manual gearbox is usually the clearest recommendation for ordinary petrol Forfour buyers. Every gear should engage cleanly when cold and after a longer drive. Test the clutch during gentle starts, reversing, hill starts and stronger acceleration in a higher gear.
Slipping, severe judder, a very high bite point or difficulty selecting first and reverse requires further investigation. Urban use can create more clutch wear than the mileage suggests, especially when the car has been driven by several inexperienced motorists.
W454 Softouch Plus
Softouch Plus is a six-speed automated manual used on selected first-generation cars. A pause during shifts is part of its operating character, but strong jolts, repeated selection of neutral, refused gears or delayed engagement are not normal. Clutch wear and actuator condition must be assessed together.
W453 twinamic
Twinamic is a six-speed dual-clutch transmission offered with the later petrol engines. It is mechanically different from Softouch and normally provides smoother, faster shifts. Test Drive and Reverse engagement, parking-speed movement, normal automatic operation and manual selection after the transmission is fully warm.
Repeated shudder, delayed take-up, gear refusal, overheating messages or a transmission warning requires diagnosis. Resetting adaptation values or clearing a warning does not demonstrate that worn clutches, actuators or control faults have been repaired.
Electric Drive and Smart EQ Forfour checks
The electric W453 was initially sold as the Forfour Electric Drive and later as the Smart EQ Forfour. It uses a rear-mounted electric motor, a lithium-ion traction battery beneath the floor and a single-speed reduction gear. It is best suited to predictable urban journeys and regular access to AC charging.
Charging speed depends heavily on the onboard charger fitted to the specific car. Confirm the specification, test charging with suitable equipment and check that the supplied cable is present. A car with a faster optional AC charger may be much easier to use than a visually identical base version.
Compare the dashboard range estimate after a full charge with the seller’s real seasonal experience. Temperature, cabin heating, driving speed and recent journeys affect the displayed figure, so one range estimate cannot determine battery health.
The vehicle should select Drive and Reverse without delay, accelerate consistently and move between power and regenerative braking without persistent high-voltage warnings. A weak 12-volt battery can prevent the vehicle from starting even when the traction battery has energy.
Do not open, touch or disconnect orange cables or high-voltage components. Battery-case damage, water intrusion, smoke, unusual heat or an electrical burning smell requires recovery and assessment by a qualified electric-vehicle workshop.
Smart Forfour reliability and common inspection areas
Smart Forfour reliability cannot be judged without identifying the generation. The W454 has conventional Mitsubishi-related front-wheel-drive mechanicals but is now exposed to age, corrosion and parts availability. The W453 is newer but adds a rear-engine cooling layout, more electronics and, on twinamic or EQ versions, more specialised drivetrain systems.
On a W453 petrol car, check the coolant level only when the engine is cold. Look for staining around the front service area, visible hoses and the rear engine compartment. Overheating, steam or sudden coolant loss means the engine must be switched off.
Inspect the W453 engine-cover seals, insulation and rear luggage floor. Check the front service panel for broken latches and make sure it is secured correctly. On both generations, damp carpets, condensation or a musty smell justify a leak investigation.
Test the central locking, windows, exterior lights, wipers, heater fan, climate control, touchscreen or audio system, parking sensors and assistance equipment. A weak battery may trigger several warnings, but replacing it does not automatically repair the charging system or an electrical drain.
If the battery symbol remains illuminated while a petrol engine is running, it indicates a charging-system fault rather than automatically proving that the battery itself has failed. Follow the charging-system warning guidance if lights, steering assistance or other electrical systems begin to fail.
Recall and service-campaign coverage depends on market, production date and VIN. Ask a Smart or Mercedes-Benz service outlet to confirm whether all applicable work has been completed instead of relying only on the absence of dashboard warnings.
Five Smart Forfour buyer checks
- Confirm the W454 or W453 generation before comparing engines or gearboxes.
- Test manual, Softouch or twinamic behaviour after a complete warm-up drive.
- Inspect W453 front service-panel fasteners, rear engine cover and cooling system.
- Operate rear-seat mechanisms, doors, windows, climate control and infotainment.
- For electric cars, verify charging equipment, battery information and warning-free operation.
Cabin space, tyres and city running costs
The first-generation Forfour can provide up to five seats depending on the rear bench, whereas the W453 is strictly a four-seater. Check the registration documents, seat belts and head restraints rather than assuming that the model name confirms the approved passenger capacity.
The W453 rear doors open close to a right angle, making child-seat installation unusually easy for such a short car. Readyspace seats can increase interior loading height, but only if the cushion mechanisms and backrest locks operate correctly.
Depending on wheel specification, Smart models may use different tyre sizes at the front and rear. Compare each tyre with the approved specification rather than fitting four matching sizes automatically. Uneven wear can indicate incorrect alignment, damaged wheels or repeated kerb impacts.
The second-generation rear-engine layout leaves only a modest luggage compartment above the powertrain. Buyers needing a more conventional boot, five seats or easier motorway performance may prefer a Fiat Panda, although condition and engine choice remain more important than body shape alone.
Running costs are lowest with a modest petrol engine, manual gearbox and smaller wheels. Softouch and twinamic add clutch and actuator exposure, the BRABUS uses costlier performance components, and the EQ requires suitable charging access even though it removes engine oil, exhaust and clutch maintenance.
Which used Smart Forfour should you shortlist?
The best Smart Forfour engine depends on generation and use. A manual W453 1.0 is the simplest modern city choice, the 0.9 turbo is more comfortable outside town, and the EQ version works best when daily distances and charging access are predictable.
| Smart Forfour version | Best suited to | What to inspect closely |
|---|---|---|
| W454 1.1 or 1.3 manual | Low-cost city driving with conventional front-wheel drive | Age-related corrosion, clutch, suspension, cooling and rear-seat mechanisms |
| W454 1.5 CDI | Regular longer journeys and higher annual mileage | Injection, turbo response, clutch, exhaust and service history |
| W454 with Softouch Plus | Buyers who specifically want two-pedal operation | Warm clutch engagement, actuator response, neutral selection and warnings |
| W453 1.0 manual | Urban driving with the simplest later petrol drivetrain | Cold start, clutch, cooling system, rear engine cover and electronics |
| W453 0.9 turbo twinamic | Mixed driving with stronger performance and automatic shifts | Turbo response, warm twinamic operation, oil history and cooling |
| Electric Drive or EQ Forfour | Predictable city mileage with dependable AC charging access | Battery information, onboard charger, cables, 12-volt battery and accident history |
Proceed when the generation and drivetrain match the paperwork, the gearbox behaves consistently and all four or five approved seating positions are complete. Reject or pause the purchase for unresolved transmission warnings, major cooling faults, serious corrosion or uncertain electric-battery condition. Stop the test drive for overheating, smoke, fuel or burning smell, red oil-pressure warning, changed braking behaviour or sudden steering-assistance loss.
- The W454 is a front-engined Mitsubishi-related car, while the W453 is rear-engined.
- A manual W453 1.0 is the simplest modern Forfour for city use.
- Softouch is an automated manual, while twinamic is a dual-clutch transmission.
- Do not judge an EQ Forfour without testing its onboard charger and 12-volt battery.
- Persistent engine, charging, gearbox or critical brake warnings require diagnosis.
FAQ
Is a used Smart Forfour reliable?
A well-maintained Forfour can be reliable, but the generation changes the answer. The W454 has conventional Mitsubishi-related mechanicals but now faces age, corrosion and parts concerns. The W453 is newer and mechanically simple with a manual petrol engine, although rear-engine cooling, twinamic and electronics require checks. Electric versions replace engine risks with battery, charger and high-voltage inspection priorities.
What is the best Smart Forfour engine?
For most second-generation buyers, the naturally aspirated 1.0-litre petrol engine with a manual gearbox is the best city-focused choice. It avoids the turbocharger and dual-clutch complexity of stronger versions. The 0.9 turbo is more suitable for hills and faster roads. W454 buyers should favour condition and service history over engine size because all first-generation cars are now substantially older.
What is the difference between W454 and W453 Forfour models?
The W454 was built from 2004 to 2006 with a front engine, front-wheel drive and Mitsubishi Colt-related engineering. The W453 arrived in 2014 with Renault Twingo-related architecture, a rear engine and rear-wheel drive. The first model could provide up to five seats, while the later car has four. Their petrol engines, automatic transmissions, service access and chassis components are not interchangeable.
Is Smart twinamic a reliable automatic gearbox?
Twinamic is a six-speed dual-clutch transmission rather than a conventional torque-converter automatic. It can operate smoothly when its clutches, actuators and control system are healthy. Test it cold and warm, particularly when selecting Drive or Reverse and during parking manoeuvres. Repeated shudder, delayed engagement, refused gears or warning messages require diagnosis. A software reset does not prove that clutch wear has been repaired.
Is Softouch the same as twinamic?
No. Softouch Plus in the first-generation W454 is an automated manual gearbox with one friction clutch and electronically controlled shifts. Twinamic in the W453 is a six-speed dual-clutch transmission. Softouch normally creates a more noticeable pause between gears. Neither should judder heavily, refuse gears or repeatedly select neutral. The correct diagnosis and parts depend on identifying the gearbox accurately.
Is the Smart EQ Forfour a good used electric car?
The EQ Forfour can be a practical electric city car when daily mileage is predictable and AC charging is readily available. Confirm the fitted onboard charger, test the charging process and check that all cables are present. Dashboard range varies with temperature and heating use, so it is not a complete battery-health test. Collision damage near the traction battery requires qualified high-voltage inspection.
What common problems should I check on a Smart Forfour?
On a W454, check corrosion, suspension, clutch, Softouch operation, cooling and older cabin electronics. On a W453, inspect the rear engine cover, cooling system, twinamic behaviour, front service panel and infotainment. Both generations need battery, tyres, brakes and water-entry checks. Electric cars add charging, 12-volt battery and high-voltage warning checks. These are inspection priorities rather than guaranteed defects.
When should I reject a used Smart Forfour?
Reject or pause the purchase when Softouch or twinamic refuses gears, the petrol engine overheats, serious corrosion affects the W454 or the electric battery and charging system cannot be assessed. Conflicting VIN, mileage or seating records also require clarification. End the road test for smoke, fuel or burning smell, a red oil-pressure warning, changed braking behaviour, multiple critical warnings or sudden loss of steering assistance.
Compare the Forfour with other used Smart models
Check whether the four-seat Forfour or a smaller two-seat Smart better matches your parking, passenger and charging requirements.