The M5 corners again!
It’s tempting to characterize the traditional flagship cars—the large, top-of-the-line sedans such as BMW’s 7-series and Mercedes-Benz’s S-class—as the ultimate embodiment of brand values. But at Bayerische Motoren Werke, that mantle rests on the M5 and the M3. For the better part of 30 years, these sports-sedan prophets have spread the good word through light-footed athleticism, steering feedback, and soulful engines. More recently, though, they have walked away from BMW dogma, the latest versions being more aloof, less feeling speed machines.
The sixth coming of the M5, internally known as F90, is BMW’s latest interpretation of its own holy creed and a reminder that, in this automotive era of rapid evolution, nothing is sacred. This 600-hp sledgehammer is the first M car equipped with all-wheel drive (excepting the X5 M and X6 M SUVs). It’s also the first M5 that will not be offered with a manual transmission.
We muttered a few profanities the first time we read those details about the drivetrain. Then we actually drove the 2018 BMW M5, and hallelujahs spilled from our lips. You’ll saw at the steering wheel as you balance the M5 at its cornering limits and the rear end wriggles under hard straight-line braking. Trail-brake it toward the apex, balance the car on the throttle, tighten your line by lifting. This is engaged driving. And fun. Those attributes were largely absent from the stoic F10-generation M5. While it’s not a return to full form, the new M5 is a solid step toward redeeming that last-generation car, which placed third out of three in its only comparison-test appearance.
The electronically controlled clutch pack technically could send equal amounts of torque to the front and rear axles, but an M engineer told us the computers never issue such a command. They always favor the rear wheels, which is evident in the overtly rear-wheel-drive nature of the M5’s dynamics. In its 4WD Sport setting with the stability control in M Dynamic mode, the M5 pivots neatly under power on corner exit. In every way, it feels like a well-balanced rear-drive car, even more than the outgoing M5, which actually is rear-wheel drive.
This new M5 can be rear-wheel drive, too, although you’ll have to fully disable the stability control before you can access that setting in the iDrive system. BMW calls it 2WD mode, but it just as accurately could have called it Drift mode—as Mercedes-AMG does with the E63 S.
Holy Horsepower
The new M5’s engine won’t tie your ankle tendons to the throttle plate of a 500-hp V-10 as the E60 M5 did a dozen years ago. Nor will it worm its way into your psyche in the same way as the free-breathing 4.9-liter V-8 from the E39-generation car. We’re rapidly moving away from the era when factory hot rods are made using a warehouse’s worth of special hardware. The turbochargers and transmissions that grease fuel-economy tests for volume models are the same building blocks for modern performance cars. The M5 is one of more than 10 current BMW models built around a twin-turbo 4.4-liter V-8, an eight-speed automatic transmission, and a rear-biased all-wheel-drive system.
There’s also the 456-hp M550i xDrive that BMW sells at a more than $30,000 discount to the M5. Admittedly, the M5’s engine features a long list of hardware changes from the M550i’s version and has an entirely different engine code. An evolution of the S63T0 that powered the outgoing car, the new M5’s powerplant wears new turbochargers making 24.5 psi of boost (up from 21.8 in the old M5), and it sprays fuel into the cylinders at higher pressures. Its 600 horsepower is an increase of 40 over the outgoing car, while peak torque rises from 502 to 553 lb-ft. That may not sound all that impressive in an era when it takes 700 horsepower to really raise eyebrows, but the M5 launches down a highway on-ramp with the authority and unrelenting thrust of a Saturn V rocket. It should clip 60 mph in 3.1 seconds.
The engine broadcasts a more complex and slightly hollow thunder that sounds more convincing than the bassy monotone of the last car. A pair of butterfly valves in the exhaust modulate the tone, yet when you deactivate the exhaust’s sport mode, the audible sensation is one of wires being yanked out of a couple of low-fidelity speakers.
BMW developed the manual transmission of the outgoing F10-generation M5 specifically for the U.S. market, only to see fewer than 5 percent of buyers choose it. So while we’ll lament the loss of another Save the Manuals! evangelist, the stick shift is unlikely to be missed by the bulk of those who will actually plunk down $103,595—plus an estimated $1700 gas-guzzler tax—on this 5-series. (And even we didn’t think the manual was very good.)
In place of the outgoing M5’s seven-speed dual-clutch automatic, the new car uses an eight-speed automatic that is technically flawless. It shifts so rapidly as to mask any momentary, infinitesimal torque reduction and picks the right ratio at the right time.
Exorcised
In 2018, the character of an M car stems not just from what’s added to the donor model but also from what’s removed. In the case of this M5, that results in a much purer sports sedan closer to M’s founding beliefs. There is no planetary gearset that varies the steering ratio with vehicle speed, no active anti-roll bars, no rear-wheel steering. Those heavy-handed chassis technologies react to the road so the driver doesn’t have to, and in turn they overmanage the 5-series into an indifferent and inert car.
Instead, the M5 uses a simpler variable-ratio steering rack that’s common in the luxury-sports-sedan segment, backed with well-weighted electric power assist. The Active M electronically controlled limited-slip rear differential helped the optional 20-inch Pirelli P Zero tires on our car lay down torque with a sense of control. Electronically adjustable dampers offer three settings, but we never found good reason to leave the softest Comfort setting for long.
BMW claims this new M5 is lighter than last year’s model, a remarkable feat considering the triple-digit weight penalty of the all-wheel-drive system. The savings come from a lighter body shell with a standard carbon-fiber roof and relentless attention to detail throughout the rest of the car. Optional carbon-ceramic brakes will save an additional 51 pounds and should be considered a mandatory buy for anyone visiting the track in this 4350-pounder. The brake pedal quickly went soft during our day lapping Portugal’s old Formula 1 circuit, although our braking points on the track remained fairly consistent.
Finding the Faith
M engineers, of course, must work with the base car they’re given, and so they’re powerless to do anything about the current 5-series’ long and wide body. Inside the well-trimmed cabin, driver and passenger sit far enough apart that they might as well be in marriage counseling. At least that leaves adequate real estate for the sundry buttons to fiddle with the throttle calibration, transmission shift speed, steering weight, damper stiffness, and exhaust mode.
The 2018 BMW M5’s born-again chassis dynamics suggest that the M division is turning back toward its faith in driver engagement. But M is, after all, a subordinate organization of the bigger enterprise, and, as such, the division’s complete redemption is only possible if the larger BMW brand can find the same religion and infuse it into the core products.
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