2008 BMW 135i Convertible
The 2008 BMW 135i Convertible is a convertible. It has a 3.0-litre turbocharged six-cylinder engine producing 300 hp (224 kW), with a 6-speed automatic and rear-wheel drive. 0–60 mph takes 5.2 seconds and top speed is 155 mph (249 km/h).
ABOUT THE 2008 BMW 135I CONVERTIBLE
The 2008 BMW 135i Convertible is the most powerful open-top version of the first-generation 1 Series (E88), a four-seat soft-top that went on sale in the US during the 2008 model year. It is powered by the twin-turbocharged 3.0-litre N54 inline-six, rated at 300 hp and 300 lb-ft, and drives the rear wheels. This entry covers the version with the six-speed automatic; a six-speed manual was also available.
Small car, big engine
The 135i shared its N54 engine with the 335i, giving a compact convertible genuinely strong performance. Its torque arrives low in the rev range, so it feels quick even at moderate engine speeds. Standard equipment included sport suspension and larger brakes than the 128i, and the fabric roof is fully power-operated.
Practicality
The convertible seats four, though the rear seats are best for children or short trips, and boot space is reduced when the roof is folded. The fabric roof keeps the car’s profile neat when closed and is quicker and lighter than a folding hard-top, but it is worth checking for wear and water leaks on older cars.
Buying one today
The early N54 has well-known weak points: high-pressure fuel pump failures, leaking fuel injectors, wastegate rattle on the turbochargers, electric water pump failure, and oil leaks from the valve cover and oil filter housing gaskets. Carbon build-up on the intake valves is also common because it is a direct-injection engine. A thorough service history is important.
Rivals
The 135i Convertible had few direct rivals; buyers might also have considered the Audi A4 Cabriolet, the Volvo C70, the Ford Mustang GT convertible or the Mercedes-Benz SLK350.
Written by CarDetails.org. Last reviewed October 31, 2026.
SPECS
| Make | BMW | Model | 135i Convertible |
|---|---|---|---|
| Year | 2008 | Version / Trim | BMW 2008 135i Convertible |
| Body Style | Convertible | Doors | 2 |
| Seats | 4 | Ext. Colour | Alpine White, Jet Black, Black Sapphire Metallic, Titanium Silver Metallic, Space Gray Metallic, Sparkling Graphite Metallic, Montego Blue Metallic, Monaco Blue Metallic, Crimson Red, Chestnut Bronze Metallic, Le Mans Blue Metallic |
| Steering | LHD / RHD | Manufactured In | Germany |
| Drive | Rear-Wheel Drive (RWD) | Transmission | Automatic (S6) |
| Engine | 3.0L 6-cyl Turbo | Engine Size | 3,000 cc |
| Power | 300 hp / 224 kW | Torque | 400 Nm / 300 lb-ft |
| 0–60 mph (0–97 km/h) | 5.2 sec | Top Speed | 155 mph (249 km/h) |
| Fuel Economy | 17 mpg city / 26 mpg hwy | ||
| Wheelbase | 2,660 mm | Kerb Weight | 1,420 kg (3,131 lb) |
HOW IT COMPARES WITH OTHER 2008 CONVERTIBLES
Compared with other 2008 convertibles in our database, its 300 hp is 5% less than the average 2008 convertible (317 hp), and it reaches 60 mph 0.9 seconds quicker than average, and it is 11% lighter than the typical convertible.
| 2008 BMW 135i Convertible | Average 2008 convertibles | Difference | |
|---|---|---|---|
| Power | 300 hp | 317 hp (18 cars) | -5% |
| Torque | 400 Nm | 396 Nm (18 cars) | +1% |
| 0–60 mph | 5.2 s | 6.1 s (16 cars) | -15% |
| Top speed | 155 mph | 144 mph (16 cars) | +8% |
| Kerb weight | 1,420 kg | 1,596 kg (19 cars) | -11% |
| Engine size | 3,000 cc | 3,634 cc (19 cars) | -17% |
Averages are calculated from all cars of the same model year and body type in the CarDetails.org database that have the figure listed. For 0–60 mph, a negative difference means quicker.
CLOSEST RIVALS
Other 2008 convertibles with similar power to the 2008 BMW 135i Convertible.
| Car | Power | 0–60 mph | Kerb weight |
|---|---|---|---|
| 2008 BMW 135i Convertible | 300 hp | 5.2 s | 1,420 kg |
| 2008 Audi RS4 Cabriolet | 340 hp | — | 1,750 kg |
| 2008 Volvo C70 Convertible | 236 hp | 7.5 s | 1,560 kg |