BMW B58 Engine Guide

The B58 is a BMW 3.0-liter turbocharged inline six. BMW introduced it in the 2016 340i, where it replaced the N55-powered 335i. It displaces 2,998 cc and uses a single twin-scroll turbocharger with an air-to-liquid intercooler, direct injection, Valvetronic and Double VANOS.

Where you find it

BMW announced the 340i on May 7, 2015 as the first B58 model. Production began in 2015. BMW's 2020 press release names the M340i, Z4 M40i, X3 M40i and X4 M40i. Wikipedia adds the 440i, M240i, 540i, 740i, X5 xDrive40i and X7 xDrive40i, plus a version in Toyota's GR Supra.

BMW service bulletins list B58 cars across the 2, 3, 4, 5, 7 and 8 Series, the 6 Series Gran Turismo, the X3, X4, X5, X6 and X7, and the Z4. Confirm your engine by VIN.

Known wear items

Oil filter housing and coolant vent hose

Motronix, an independent BMW shop, says the primary source of coolant leaks near the oil filter housing is the small plastic vent hose to the expansion tank. It says the hose is severely weakened after about 60,000 to 80,000 miles. Signs include a sweet coolant smell, a dropping coolant level or low coolant warning, and chalky residue near the housing. Their repair replaces the housing gasket kit, the vent hose and the single-use bolts.

BMW bulletin SI B11 01 20 says on rare occasions during an oil service, the Genuine filter insert is hard to remove or breaks apart inside the housing. When it breaks apart, the bulletin calls for a complete new housing, covered by BMW's New Vehicle Limited Warranty.

IA EURO illustration of the BMW B58 oil filter housing, numbered: filter cap, oil filter element, housing body, coolant connection, oil to coolant heat exchanger, with failure marks for the housing gasket and the filter insert — B58 oil filter housing: 1 filter cap, 2 oil filter element, 3 housing body, 4 coolant connection, 5 oil to coolant heat exchanger. The filter, oil cooler and bypass valves all sit in this one plastic housing. Black ! marks: the housing gasket, which leaks oil and coolant, and the filter insert, which BMW's bulletin SI B11 01 20 says can break apart inside the housing.

IA EURO illustration of the BMW B58 heat management module on the engine block, numbered: heat management module, coolant pump, short circuit line, heater return, radiator return — B58 heat management module: an electric rotary valve in place of a wax thermostat. 1 heat management module, 2 coolant pump, 3 short circuit line, 4 heater return, 5 radiator return.

Valve cover and PCV valve

Excella Automotive says the B58's PCV valve is a diaphragm built into the valve cover, so a failed PCV often means a new valve cover. It lists signs owners may notice: a whistle or hiss from the engine bay, white or bluish exhaust smoke, rising oil use, oil leaks around the cover and a rough idle.

IA EURO illustration of the BMW B58 valve cover underside, numbered: full load oil separator, part load oil separator, high pressure fuel pump mount, cylinder head cover, with a failure mark for the PCV diaphragm — Where the PCV lives: the B58 separates oil from blow-by inside the valve cover in two stages. 1 full load oil separator, 2 part load oil separator, 3 high pressure fuel pump mount, 4 cylinder head cover. The black ! marks the PCV diaphragm on top of the cover, the part that splits (BMW's bulletin SI B01 14 23 extends its warranty on Gen 1 US cars).

Low temperature coolant circuit on the X5, X6 and X7

BMW bulletin SI B17 02 20 covers the X5, X6 and X7 with the B58C engine built up to August 26, 2019. Signs are coolant traces under the vehicle or coolant loss, sometimes with weak air conditioning. BMW gives the cause as premature breakdown of the coolant with gassing. The fix is to drain and refill the low temperature cooling system twice with BMW-approved coolant, covered by the New Vehicle Limited Warranty.

Spark plugs and ignition coils

A BMW dealer's service article lists rough idle, hesitation, starting trouble, reduced power and a check engine light as signs of a failing coil. It adds that testing should guide the repair, since several faults can set the same code.

BMW recall: engine software and brake assist

NHTSA campaign 21V-598 covers certain 2020 M340i, 540i and X3 M40i, 2020-2021 X4 M40i and 745Le xDrive, 2019-2021 Z4 M40i and 2020-2021 Toyota Supra. During engine start, the engine management software may cause loss of braking assist. Dealers update the software free of charge. Check any B58 car for open recalls by VIN.

Oil and routine service

BMW SI B11 01 15 (Feb 2017) lists 0W-20 BMW Longlife-14 FE+ oil for the B58 from model year 2016. Its chart gives 6.5 quarts (6.25 liters) for the 3 Series (F30) and 6.9 quarts (6.5 liters) for the 5 Series (G30) and 7 Series (G12). It does not list later cars such as the X3 M40i, so check the owner's manual.

An oil reference site says many cars once listed for Longlife-14 FE+ now reference the newer Longlife-17 FE+, and to follow the approval in your vehicle documentation. Liqui Moly announced that Top Tec 6600 0W-20 would carry the BMW Longlife-17 FE+ approval. Match the approval in your owner's manual before you order oil.

What we carry:

B58 oil change kit, 7 L: 2016-2020 cars such as the 340i and 740i, with Liqui Moly Top Tec 6600 0W-20 and a Mann HU 6022 Z filter
B58 oil change kit, 8 L: 2018-2020 X3 M40i, X4 M40i and M340i xDrive
Oil filter: Mann HU 6022 Z
Oil filter housing gasket set: Elring 784.620, set of 5
Oil cooler gasket set: Elring 784.680, set of 4
Engine air filters: Mahle LX5549, Mann C 27 045 and Mann C 28 037
Spark plugs: Beru Z366 and Bosch 8169
Ignition coil: Bosch 0986221124
Coil and plug kits: 2016-2020 with Beru plugs and 2019-2020 with NGK plugs
Cabin filters: Hengst E2991LC and Hengst E4980LC

Before you buy

Filters, plugs and oil quantity change with model and year, so do not order by engine code alone. Confirm your part by VIN on our fitment check page. You can also find your part number, read our BMW fluids guide, or browse all our B58 parts.