BMW 7 Series G11/G12 Engines — The Complete UK Guide

“The B57 is BMW's modular straight-six diesel and one of the most refined diesel engines ever fitted to a 7 Series. The 730d delivers 265 bhp and 620 Nm of torque; the 740d ups that to 320 bhp and 680 Nm. Both offer effortless performance and genuine 40+ MPG economy. Unlike the quad-turbo 750d, the single and twin-turbo B57s are proven, durable, and free of excessive complexity. It's the diesel that defines this generation.”

Who it's for: buyers who want flagship luxury with diesel economy and proven reliability.

“The B58 is BMW's modular straight-six and arguably the best engine ever fitted to a 7 Series — 326 bhp pre-LCI, rising to 340 bhp post-LCI. It's smooth, responsive, and so reliable that Toyota uses it in the Supra. The 740i is the sweet spot in the petrol range — six-cylinder refinement, V8-rivalling performance, and none of the N63's complexity or the V12's running costs. It's the 7 Series engine for people who actually drive their cars.”

Who it's for: buyers who want the best all-round petrol 7 Series without the V8's maintenance bills.

“The N63 V8 is a glorious engine — 449 bhp, 650 Nm, and a soundtrack that defines the 7 Series experience. But it carries BMW's 'hot-vee' design, where the turbos sit inside the V of the engine, generating significant heat. Valve stem seals harden and cause blue smoke on startup; cooling system components fail prematurely; and the alternator bracket gasket is prone to oil leaks. The post-LCI N63B44TÜ3 (523 bhp) is improved but still carries more risk than the B58.”

Who it's for: buyers who want V8 power and are prepared for V8 maintenance costs.

“The N74 V12 is BMW's final production V12 — 609 bhp, 800 Nm, and a straight-line performance that's genuinely staggering (0-60 in 3.6 seconds). It's also one of the most expensive engines to maintain: parts are rare, labour is specialist-only, and the engine bay is tightly packed. A full V12 replacement can exceed £15,000. Only 5,000+ M760Li examples were built, making them rare but costly to own.”

Who it's for: collectors who want BMW's final V12 and have the budget to maintain it.

“The 730d delivers 265 bhp, 620 Nm, and genuine 45+ MPG economy in a full-size luxury saloon. It's the entry point to the diesel range but punches above its weight — six-cylinder refinement, proven B57 durability, and none of the quad-turbo complexity of the 750d. It's the sensible choice that still delivers the 7 Series experience.”

Who it's for: buyers who want flagship luxury with the lowest running costs.

“The 745e replaced the 740e's four-cylinder with a B58 six-cylinder, delivering 394 bhp system output and an electric range of up to 36 miles. It's often overlooked in favour of the V8s and diesels, but it's the most advanced powertrain in the range — six-cylinder refinement, electric-only city driving, and genuine performance. It's the 7 Series for buyers who want future-proof luxury.”

Who it's for: buyers who want the most technologically advanced 7 Series and can charge at home.