Skip advert
Advertisement

Mercedes SL400 2014 review

New twin-turbo V6 kicks off flagship sports car range

Find your Mercedes SL
Compare deals from trusted partners on this car and previous models.
Or are you looking to sell your car?
Value my car
Fast, no-nonsense car selling
Value my car

The entry point to Mercedes SL ownership is now better than it ever was. In fact, it makes recommending the SL500 that much harder. The SL400 is still not the car for everyone – it feels too comfortable and removed from the action to be called a sports car in the same vein as the 911. But if comfortable cruising is your thing, it’s an excellent choice.

Advertisement - Article continues below

The SL350 is out and the SL400 is in as part of a new line-up for Mercedes’ flagship sports car. A 329bhp 3.0-litre twin-turbo V6 replaces the old 3.5 naturally aspirated engine, providing 27bhp more power for the same price. 

As a result the 0-62mph time drops from 5.9 to 5.2 seconds, giving just the kind of SL performance you want. There’s plenty of torque from low revs and a nice – but muted – exhaust rasp. It all feels less effort than in the old V6.

That easy comfort is what the SL is all about. Our car had Active Body Control air-suspension, which gives a really nice, cushioned ride – the standard springs are nearly as good, too. Over potholes the SL can’t disguise those heavy 19-inch rims sending a jolt into the cabin, but on the plus side it’s just as refined as an E-Class, making for relaxing motorway journeys.

As for handling, it’s on the relaxing side of sporty. It feels planted and predictable, with quick steering. You can’t help but be impressed by how the body stays flat through bends or the tyres refuse to lose grip, but a BMW 6 Series Convertible or Porsche 911 Cabrio are more intense and involving.

Oddly, this engine is no more fuel efficient than the one it replaces – it’s actually a little worse. Economy goes from 37.7mpg to 36.7mpg, and CO2 emissions are up from 169g/km to 178g/km. That’ll cost an extra £55 in road tax for the first year, but otherwise it’s a marginal difference.

With leather, sat-nav, parking sensors, heated seats and xenons, the £72,500 SL400 costs about the same as a 640i Convertible and £15,000 less than a 911 Cabrio. It’s not quite as much fun as either, but for comfort, refinement and style, the SL has got both licked.

Skip advert
Advertisement

New & used car deals

Mercedes SL Class

Mercedes SL Class

RRP £110,030Used from £67,490
Kia Sportage

Kia Sportage

RRP £28,085Avg. savings £3,239 off RRP*Used from £12,990
Nissan Juke

Nissan Juke

RRP £19,805Avg. savings £4,614 off RRP*Used from £8,999
Hyundai Tucson

Hyundai Tucson

RRP £29,840Avg. savings £5,624 off RRP*Used from £12,124
* Average savings are calculated daily based on the best dealer prices on Auto Express vs manufacturer RRP
Skip advert
Advertisement

Most Popular

New Honda Super-N 2026 review: little EV is fun and full of character
Honda Super-N and Richard Ingram

New Honda Super-N 2026 review: little EV is fun and full of character

Honda's quirky Super-N is compromised on paper, but in reality it's a fun and efficient small EV
Road tests
19 Jun 2026
Renault 5 and Renault 4 could get even cheaper thanks to Twingo’s battery tech
Renault 5 E-Tech Iconic Five - front action

Renault 5 and Renault 4 could get even cheaper thanks to Twingo’s battery tech

The Renault 5 and Renault 4 will eventually get LFP tech to help make them even more accessible
News
19 Jun 2026
Chery Tiggo 9 vs MGS9: a budget Chinese 7-seater SUV showdown
Chery Tiggo 9 vs MGS9 - front tracking

Chery Tiggo 9 vs MGS9: a budget Chinese 7-seater SUV showdown

We pit the biggest seven-seaters from MG and Chery into battle. Will the MGS9 or Tiggo 9 lead the revolution?
Car group tests
20 Jun 2026