F90 M5 vs G90 M5: Which BMW M5 Should You Buy?

Two M5s, two completely different philosophies. The F90 (2018–2023) is the last pure-combustion M5: a 4.4-liter S63 twin-turbo V8, M xDrive with a rear-drive party trick, and a curb weight that suddenly looks almost svelte. The G90 (2025-on) is the first electrified M5 — a plug-in hybrid pushing 717 hp through a chassis that weighs about as much as an X5.

With clean F90s now trading well below original sticker and the G90 fully landed in showrooms, this is the cross-shop we get asked about most. Here's how the two actually stack up — on paper, on track, in the service bay, and on the dyno.

Two Very Different Recipes

The F90 runs the S63B44T4, a hot-vee 4.4-liter twin-turbo V8 making 600 hp in base form, 617 hp in the Competition, and 627 hp in the sold-out M5 CS, all backed by 553 lb-ft of torque and the ZF 8-speed. M xDrive defaults to all-wheel drive but will send everything rearward in 2WD mode when you want smoke.

The G90 keeps a 4.4-liter twin-turbo V8 — now the S68 — and adds a 194-hp electric motor inside the transmission for a combined 717 hp and 738 lb-ft. It plugs in, it drives silently around town, and for the first time in the US you can have it as a G99 Touring wagon. On paper it's the most powerful production M5 ever. On the scales, it's also comfortably the heaviest.

The Numbers — and the Weight Problem

Line them up and the story gets interesting:

• Power: G90 wins outright — 717 hp vs 600–627 hp for the F90 family, plus a 185 lb-ft torque advantage.
• Weight: the F90 weighs in around 4,100 lb as tested; the G90 is a 5,390-lb car. That's well over half a ton of extra mass the hybrid hardware has to justify.
• 0–60 mph: instrumented tests put the F90 at about 3.1 seconds against roughly 3.3 for the G90 — the paper power advantage doesn't survive the weigh-in.
• Quarter mile: around 11.7 seconds for the F90, 11.9 for the G90 in the same head-to-head testing.

Independent drag races between the two generations have repeatedly shown the older car edging the new one in a straight line. But don't write the G90 off as a barge: at the Nürburgring GP circuit it clocked a 1:37.15, coming within inches of the F90 M5 CS's time despite carrying roughly 2.4 tons. The chassis engineering hiding that mass is genuinely remarkable. The mass still exists, though — and on a track day you'll pay for it in pads, rotors, and tires long before the lap timer notices.

Ownership: What to Check Before You Buy

The F90 has matured into a known quantity, and the news is mostly good — recent used-market reviews still rate it one of the strongest performance buys on the market. That said, there are three things every F90 shopper should verify:

Coolant expansion tank. The original plastic tank sits directly above the driver-side fuel injectors, and the seam can micro-crack under engine-bay heat — dripping coolant onto injectors, coils, and in bad cases the ECU. BMW revised the part in late 2020, so on 2018–2020 cars, confirm the updated tank is fitted or budget to replace it immediately. Our F90 M5 cooling catalog covers the tank and the rest of the system.

Rod bearings. The S63 is far less notorious than the old S65/S85, but bearings remain the S63 family's known wear item. On a higher-mileage or tuned car with no bearing receipts, preventative replacement is cheap insurance against a five-figure engine rebuild — walk away from any car with rod knock or glitter in the oil.

The usual V8 consumables. VANOS solenoids, ignition coils, and plugs are routine-maintenance items, especially on tuned cars. None of it is scary; all of it should be documented.

The G90 is too new for a pattern of faults — you're buying under full warranty. The ownership math there is simpler but not free: a 5,390-lb car eats tires and brakes at a rate the F90 doesn't, and hybrid-system service will eventually be a line item no S63 owner ever sees.

Tuning Headroom and the Aftermarket

This is where the F90 runs away with it. The S63 is one of the most tune-friendly V8s BMW has ever built: a conservative ECU calibration means a reputable stage 1 tune alone typically unlocks a healthy triple-digit torque bump, and with downpipes and supporting mods, 700+ crank horsepower is well-trodden territory. Eight years of aftermarket development means intakes, heat exchangers, exhausts, suspension, and brake upgrades are all mature and proven — browse the full F90 M5 parts catalog to see how deep the bench is.

The G90 aftermarket is younger but moving fast. Exhausts, wheels, suspension, and cooling upgrades landed first, while tuners are still working through the hybrid powertrain's control logic — the ceiling is enormous, but the software is a harder nut to crack than a pure-combustion S63. Our G90/G99 M5 parts range is growing with the platform.

The Verdict

Buy the F90 if you want the sharper driver's car, the deeper aftermarket, and the last naturally analog(ish) M5 — at a used price that undercuts the G90 by a wide margin. It's lighter, it's quicker in a straight line as delivered, and it has vastly more proven tuning headroom. Just buy on service history, not on price.

Buy the G90 if you want the most capable all-around M5 ever sold: silent EV commuting, a full factory warranty, staggering rolling-road pace once the electric torque fills in, and — finally — a Touring option. Owners on the G90 forum are largely smitten; this Bimmerpost owner review sums up the honeymoon well. The weight is real, but so is the engineering that manages it.

FAQ

Is the F90 M5 faster than the G90 M5?

In instrumented straight-line tests, yes — the F90 runs roughly 3.1 seconds to 60 mph against about 3.3 for the G90, despite giving up around 100 hp. The G90's extra half-ton-plus of mass is the difference. On a circuit, the gap narrows dramatically.

What should I check before buying a used F90 M5?

The three big ones: the revised coolant expansion tank on 2018–2020 cars, rod bearing history on higher-mileage or tuned examples, and complete service records covering VANOS solenoids, coils, and plugs.

Can the G90 M5 be tuned?

The bolt-on aftermarket (exhaust, suspension, wheels, cooling) is already active, but hybrid powertrain software tuning is still maturing. The S68 has strong headroom; give the tuners time.

Which M5 is cheaper to run?

Short-term, the G90 — it's under full warranty. Long-term, a sorted F90 with the tank and bearing questions answered is a simpler, cheaper car to keep, though it consumes fuel the way a 600-hp V8 should.

Whichever generation wins your garage spot, shop our full F90 M5 parts collection to build it your way.