BMW 4 Series Buyer's Guide
The 4 Series is the two-door 3 Series by another name, and at auction it is really an M4 market with some diesel coupés underneath. We have no sold results yet, but eight active listings sketch the range: 420d coupés estimated at £9,000–10,000 and £11,000–12,000 at one end, an 8,000-mile M4 CSL at £78,000–88,000 at the other.
Know your generations
The F32 (2013–2020) was the first car to wear the badge, splitting the coupé, convertible (F33) and Gran Coupé (F36) off from the F30 saloon. Mainstream engines run from the 184bhp 420i and 190bhp 420d through the 306bhp 435i to the 326bhp 440i, the last two carrying BMW's strong N55 and B58 sixes. The F82 M4 (2014–2020) brought the 425bhp twin-turbo S55, with Competition (450bhp), the water-injected GTS of 2016 (500bhp) and the 2017–2018 CS (460bhp) above it.
The G22 (2020 on) grew the grille and the footprint; 420i, 430i and the excellent 374bhp M440i cover the civilian range. The G82 M4 offers 473bhp standard (available with a manual gearbox), 503bhp as the Competition and Competition xDrive, and the 543bhp CSL of 2022–2023, built in limited numbers.
What to pay
Nothing has hammered through our records yet, so estimates from live lots are the only anchors. Diesel F32 coupés: £9,000–10,000 for a 2015 420d xDrive M Sport, £11,000–12,000 for a 2017 420d M Sport. F82 M4s: £15,000–16,000 for one 2015 car, £20,000–30,000 for another, and £30,000–50,000 for a 2017 G-Power-converted example. G82 money is stronger: £50,000–75,000 for a 2023 manual M4, £75,000–100,000 for a 2024 M4 CS, and £78,000–88,000 for a 2022 M4 CSL, one of 100 UK-supplied cars with 8,000 miles. Treat all of these as asking-range signals rather than proof of value until sales land.
What goes wrong
The F82 M4's S55 has a documented crank-hub concern on tuned cars: the friction-fit hub can slip under significantly raised torque, which wrecks the engine. Standard-power cars rarely suffer; buy unmapped or budget for a pinned hub. Charge-pipe plastics crack, and early DCT cars need their transmission service history checked. The 420d shares the B47 diesel's timing-chain and EGR-cooler recalls; confirm the recall work is done. F32 sixes (435i N55, 440i B58) are durable, with oil-filter housing gaskets and water pumps the routine items. G82 cars are too young for a pattern beyond expensive consumables: carbon-ceramic discs, where fitted, cost thousands per axle to replace, and kerbed 19s and 20s are the norm at auction.
Our view
The civilian diesels at £9,000–12,000 estimates are depreciating transport and will keep depreciating. The cars worth holding are the manual sixes: a B58 440i is a durable, genuinely quick coupé the market has not yet noticed, and a standard, unmapped F82 M4 around the £20,000–30,000 estimate band is a lot of motor for the money provided the crank hub and history check out. The CSL and CS will do what limited-run M cars always do; the £78,000–88,000 estimate on an 8,000-mile CSL suggests the market has already priced that in.
