BMW does not fit one gearbox to its cars. Depending on the model, the year, the drivetrain layout and whether it’s an M car, you could be looking at a ZF torque-converter automatic, a dual-clutch M DCT, a seven-speed wet-clutch DCT for a front-wheel-drive 1 Series, a hybrid-specific 8-speed, or a traditional six-speed manual.

MT Auto Parts is a specialist BMW breaker in Thurnscoe, South Yorkshire. The business dismantles F, G and U generation BMWs, that’s the 2012-onwards range across the 1 to 8 Series, X1 to X7, Z4 and the electric models. The gearboxes, transfer boxes, differentials, driveshafts and transmission control units recovered from those vehicles are available to private buyers and trade customers throughout the UK mainland.

“People often ring us expecting to describe their car and be told we’ve only got one option,” a company spokesperson said. “In practice we hold multiple variants, different mileage bands, different specs, rear-wheel drive and all-wheel drive. The BMW gearbox range from 2012 onwards is more varied than most people realise, and our stock reflects that.”

Not One Gearbox, Many

The 2012-onwards BMW range spans three distinct generations and a huge variety of models. A 2016 116i hatchback, a 2019 M4 Competition, a 2021 X5 xDrive45e plug-in hybrid and a 2023 M5 all carry entirely different transmission architectures. Sourcing a replacement gearbox for any one of them means knowing exactly which unit was fitted, and finding one in usable condition.

MT Auto Parts holds stock across all the main BMW gearbox families from this era. Some of the examples include:

• Rear-wheel-drive ZF 8-speed automatics (GA8HP51Z) – the most common automatic in the F and G generation range. Fitted to the 3, 5, 6 Series and X4 in standard rear-drive form. Multiple mileage bands; prices from around £330 to £1,435.
• All-wheel-drive ZF 8-speed automatics (GA8HP51X, GA8HP76DZ) – the xDrive variants. Common in the X3 xDrive, larger X5 and X7 configurations. Units priced from around £1,000 to £1,580.
• M xDrive 8-speed automatics (GA8X76AZ) – the performance version fitted to the X5 M, X6 M and M5. Different clutch packs and software calibration from the standard 8HP family. Current stock from £2,250 to £2,999.
• M Sport dual-clutch DCT – GS7D70SG (seven-speed, M5/M6) and GS7D36SG (six-speed, M2/M3/M4). These are not automatic gearboxes in the torque-converter sense; they’re a twin-clutch design built specifically for the M cars. GS7D70SG from £703 to £2,099 depending on mileage; GS7D36SG from £1,499 to £2,499.
• Front-wheel-drive and all-wheel-drive 7-speed DCT (GD7030AG / GD7F32AG) – the dual-clutch unit fitted to UKL-platform BMWs: the F20/F21 1 Series with auto transmission, F45/F46 2 Series Active Tourer, and F48 X1. An entirely different unit from anything in the rear-drive range. From around £332.
• Hybrid-specific 8-speed (8HP75HZ / 8P75HZ) – the transmission used in plug-in hybrid and mild hybrid 5 and 7 Series. Modified to integrate with the electric motor and battery management system. Current stock at £2,327.
• Six-speed manual (GS6-58DG) – fitted to certain F-generation 1 and 2 Series variants. Less common through the breaker trade than automatics, but available. Current listing at 765 miles, £379.99.
• Near-new F70 twin-clutch unit (GN7Q40SC) — a unit from the latest-generation 1 Series, recorded at 353 miles. Currently listed at £4,399.99. Available because the donor vehicle was written off, not because the gearbox was worn.

The M Cars: A Different Category Altogether

It’s worth separating the M car gearboxes, because they behave differently in the used parts market. Standard automatic units come through in volume. There are a lot of F30 3 Series and F10 5 Series being broken every week. M cars are scarcer, which means M gearboxes are scarcer too.

The GS7D70SG – the M DCT fitted to the F10 M5 and F12/F13 M6, is a unit that M car owners and specialist garages actively search for. MT Auto Parts holds several at any one time, across a range of mileages. A higher-mileage spare/repair unit starts from £703; a low-mileage clean example runs to £2,099. There are options in between. For an M5 or M6 owner facing a gearbox bill from an independent BMW specialist, the difference between a dealer-sourced exchange unit and a quality used one is significant.

The GS7D36SG – the six-speed M DCT in the F80 M3, F82 M4 and M2 Competition, is similarly in demand. These are cars where owners tend to be knowledgeable and specific about what they want; the DCT option on the M4 was available before BMW moved to the ZF automatic for later models, and buyers looking to preserve that character look for it carefully. Units in stock from around £1,499 to £2,499 depending on condition and mileage.

Both M DCT families require proper adaptation after installation, clutch bite-point learning and gear selector calibration using a BMW-capable diagnostic tool. This is not optional. Any workshop quoting for an M DCT swap should factor it into the estimate.

Beyond the Gearbox: Transfer Boxes, Differentials and Driveshafts

A gearbox failure on an xDrive BMW doesn’t always mean just the gearbox. The transfer box, the unit that splits torque between the front and rear axles, is a separate component, and it has its own wear pattern. MT Auto Parts stocks transfer boxes (ATC13, ATCL45L and related variants) from £309 to £1,299 depending on type. For a diagnosis that points at the transfer box rather than the main gearbox, a used replacement unit is often a realistic repair path.

Front and rear differentials are stocked too. Front differentials from £227; rear differentials from around £459 to £759. These come into play on both standard and M xDrive models. A rear diff failure on an M5 or X5 M is an expensive dealer repair; a quality used unit from a low-mileage donor changes the maths considerably.

Driveshafts are available front and rear, from £225 to £406. And for buyers looking at a gearbox swap who also need the control module: Transmission Control Units (TCUs) are stocked at £854.99. TCUs on modern BMW automatics are part-number specific and require coding after fitment. They cannot be swapped freely between vehicles. VIN confirmation is strongly recommended before purchase.

How Parts Are Described: Condition, Mileage, Transparency

Every listing at MT Auto Parts states the part’s condition clearly. Three categories are used:

• VERY GOOD – the unit is in excellent used condition with no known faults. Ready to fit.
• GOOD – normal used condition with wear appropriate to the mileage stated. Suitable for direct replacement.
• WORN – listed explicitly as a spares or repairs item. Priced accordingly. Suitable for rebuilders or those needing sub-assemblies.

Mileage is recorded from the donor vehicle’s history at the point of dismantling and is stated on every listing. For used BMW gearboxes, this matters more than for most parts. An automatic transmission’s wear is closely tied to its service history, and a buyer should know what they’re dealing with before committing. MT Auto Parts processes VIN confirmation requests before purchase, particularly important for BMW automatic gearboxes where the same family can include multiple variants with different clutch specs, software versions and oil pump configurations depending on model year and build date.

Clutch kits are also stocked for manual gearbox applications, a complete petrol clutch assembly from an 800-mile donor at £360.99 and a LUK clutch set at £262.62. MT Auto Parts does not stock brake pads or service consumables, but a nearly new clutch assembly from a low-mileage car is a different proposition entirely.

For Workshops and Trade Buyers

Independent BMW mechanics, gearbox rebuilders and bodyshops can approach MT Auto Parts directly for stock checks and lead times. The business works with trade customers regularly, particularly for the less common units that don’t move in volume through standard channels.

A few technical notes for fitting garages:

• ZF 8HP automatic gearboxes require a full oil fill and adaptation procedure after installation. The correct fluid is ZF Lifeguard Fluid 8; this should be part of any ZF automatic quote.
• G-generation BMW models communicate gearbox control data over the ENET interface. TCU coding after a swap on these cars needs a BMW ISTA-capable diagnostic tool. Standard OBD2 scanners are not sufficient.
• M DCT units (GS7D70SG, GS7D36SG) require clutch bite-point adaptation and gear selector calibration after fitting. This step cannot be skipped.
• Almost all used BMW gearboxes sold by MT Auto Parts carry a 30-day warranty (terms and conditions apply). WORN/spares listings are an exception and are clearly labelled as such.
• Trade enquiries for specific variants or availability on recently dismantled vehicles can be directed to the team directly.

Free standard delivery to UK mainland addresses within 48 hours applies to items under 20 kg. Complete gearbox assemblies exceed this. Additional freight charges apply, and units are sent via specialist pallet carriers. Most orders go out within 24 to 48 hours of payment.

About MT Auto Parts

MT Auto Parts is a specialist BMW breaker based in Thurnscoe, South Yorkshire. The business covers BMW F, G and U generation models produced from 2012 onwards, 1 to 8 Series, X1 to X7, Z4 and the full electric range including the i3, i8, iX3, iX and i7, and holds an Environment Agency Authorised Treatment Facility permit. Parts are available across lights, alloy wheels, engines, gearboxes, exhausts, in-car entertainment, body parts, drivetrain and suspension, interior, electrical systems, restraint systems and airbags, and brakes. Almost all used parts carry a 30-day warranty (terms and conditions apply). Free standard delivery within 48 hours to all UK mainland addresses for items under 20 kg.

Website: www.mtautoparts.com