The shining star of this AMG isn't the one on the grille, it's the turbocharged four-cylinder engine under the hood. Code-named M139, this is the world's most powerful production I4 engine, producing 382 horsepower and 354 pound-feet of torque. Not impressive enough? The CLA45 S (which isn't coming to the US -- womp womp) turns up the wick to 416 hp and 369 lb-ft. Yes, 416 hp from a little 2.0-liter engine. What a world!
The eight-speed dual-clutch automatic transmission is super quick to shift and helps the CLA45 accelerate to 60 mph in a manufacturer-claimed 4 seconds. I'm not normally one to choose my own adventure with dual-clutch 'boxes, but the CLA's metal paddle shifters have great tactile action and offer instant response. Plus, there's a feisty little brapp from the exhaust every time you upshift, and this thing loves to burble its way back down on overrun.
This car drives like a giant turbocharger on wheels. Digging into the throttle is like opening and closing a boost valve. Yet even in the most aggressive Sport Plus setting, hitting the gas never feels like flicking a light switch. There's a bunch of power here, sure, but it never arrives abruptly or in weird spurts. I don't mind the occasional "turbo moment" of boost, but for as heavily reliant as this engine is on its forced-induction mechanicals, it's well behaved.
The CLA45 has a couple of neat tricks up its sleeve, one of which is Mercedes' upgraded 4Matic Plus all-wheel drive system. This isn't the same setup you'll find in the CLA250 or CLA35, which defaults to front-wheel drive and sends power rearward when demanded. Instead, the Plus tech is completely variable and can shuffle 100% of the engine's torque to the front or rear axle as needed, as well as juggle it from side to side, sending power to the wheel that warrants it most.
Plus (get it?), the CLA45 has the same Drift Mode you'll find in the AMG E63, where all of the engine's torque is locked to the rear axle. Of course, you do have to disable the traction control, put the CLA45 in its Race mode and set the transmission to manual operation, so I don't recommend pulling these rear-wheel-drive stunts on public roads. But considering the CLA45 uses front-wheel-drive architecture, the fact that Mercedes allows it to become a tail-out drift machine is a reminder that the AMG tuners in Affalterbach don't take life too seriously.
The CLA45 is a total hooligan, both sharper and better balanced than the old version. The steering is a little light in its default Comfort setting, but weights up a bit in Sport and Sport Plus. Body motions are nicely kept in check, and you really get the sense that the CLA45 likes to be pushed hard. Its nose eagerly dives into a turn and the all-wheel-drive system instantly moves power rearward to push you through the corner. Plus, its tiny footprint means it's easy to place on the road, and it never feels like some monster you constantly have to rein in. If you like the way boosted hot hatches drive (who doesn't?) then you'll love the CLA45.
I recommend springing for the $4,300 Dynamic Plus Package which gets you two-stage sport dampers, so you can choose whether or not you want the ride to be stiff or stiffer. The CLA45 isn't so harsh that you couldn't live with it every day, but the suspension is definitely an area where you'll be reminded that this Mercedes-AMG sedan errs toward the latter part of its name.
The 19-inch wheels are wrapped in 255/35-series Michelin Pilot Sport 4S tires, which provide plenty of grip while cornering, but make a lot of noise when you're just commuting down the freeway. Thankfully, at least, wind noise is kept to a minimum, due in part to the CLA's slippery shape.
Personally, I much prefer the slightly more upright proportions of the A-Class sedan to the "four-door coupe" CLA. But even so, this car is significantly more attractive than its forebear, which looked kind of dorky with its huge headlamp housings and weird taillights. This test car has all the fixings, with active LED headlights ($900) and the AMG Night Package ($750) that blacks out most of the exterior trim. Combined with the matte black wheels ($1,750) and denim blue paint ($720), this CLA45 is an attractive car, even if you have to spend quite a bit of cash to get it to this top-notch spec.
Step inside and the CLA45 boasts the same big cabin improvement as other A- and CLA-Class models. The thick-rimmed, flat-bottom steering wheel feels great in my hands, and I adore the Recaro performance seats ($2,690), which are totally comfy yet keep me firmly in place when I'm out for a fast drive. Design wise, this little AMG is nicely appointed and fashion forward, with great ambient lighting and premium materials on the surfaces I touch most. That said, there are a number of areas where you'll be reminded this is a $35,000 interior at its core, with some hard plastics on the door pockets, lower dashboard and transmission tunnel.
This is a subcompact sedan, so passenger accommodations are a little tight no matter where you sit. The rear seats are best suited for kids or backpacks, and they're not all that easy to get in and out of. Even at my relatively short stature of 5 feet, 8 inches tall, it's hard to get comfortable in the back, and while I have just enough room to sit behind the front seat as adjusted for my ideal driving position, I can't imagine trying to sit behind anyone who'd move the seat back. That swoopy roofline might be all the rage visually, but it does a number on the sedan's actual functionality (because "coupe").
In any case, the AMG 45 gets the same excellent MBUX tech you'll find in the other CLA-Class models, with a pair of 10.2-inch screens serving as the digital gauge cluster (and main multimedia interface. You'll want to use the left thumbpad on the steering wheel to interact with the left screen, which can show lots of different vehicle or trip data in an array of designs. The central display, meanwhile, can either be operated by the right thumbpad, the big trackpad on the center console or by touch. I prefer the latter two options, and MBUX has natural speech voice integration, as well -- you know, the easily provoked "Hey, Mercedes" function. Overall, I love this infotainment bundle: It's colorful, easy to use and packed with features, like Mercedes' augmented reality overlays for the navigation system. MBUX not your thing? That's fine -- Apple CarPlay and Android Auto are standard, too.
There's an impressive array of driver-assistance tech on offer in the CLA45, even if most of the good stuff requires you to fork over more cash. The $1,700 Driver Assistance Package will get you all the good stuff, including adaptive cruise control with speed limit assistance, active steering assist, blind-spot monitoring, lane-keeping assist, lane-change assist and every other "assist" you can think of. Well, except active parking assist -- that's an extra $1,090, though it also adds a surround-view camera.
By now you've probably noticed all the prices for optional add-ons, and that brings me to this car's major pain point. The 2020 Mercedes-AMG CLA45 starts right around $55,000, but the tester pictured here has illuminated door sills ($350), SiriusXM radio ($460), the Burmester surround-sound stereo ($850), a wireless charging pad ($200), all the aforementioned goodies and a few other this-and-thats, bringing its final price to $73,850, including $995 for destination. And that's not even fully loaded.
$55K is one thing, but $74K is a ton of money for one of these. For comparison, that's about $6,000 more than the starting price of a V8-powered AMG C63 sedan, or more to the point, $10,000 more than a comparably equipped Audi RS3. The CLA45 is a slightly more entertaining car than the RS3, but 10 grand is still 10 grand.
Still, that's the price you pay for this kind of ridiculous performance, and I have no doubt that every CLA45 customer will be endlessly satisfied with their choice. In the same way that the standard CLA250 is a massive step forward over its predecessor, so too is the CLA45. This little car packs a huge punch.