BMW 6-Speed Manual Transmission Guide

GS6-17BG, GS6-37BZ, GS6-45BZ, GS6-53BZ, S6S 420G, S6S 560G · six-speed manual · Getrag and ZF · US-market cars 1989-2019 · E39, E46, E60, E82, E90 family, F-series 2 to 4 Series, F87 M2

Part of the BMW transmission guide. To find the gearbox in a particular car, use the E-series lookup or the F and G series lookup.

The six-speed manuals in US BMWs built from 1989 to 2019 come from a handful of Getrag and ZF gearboxes. BMW names them by a letter code: D, E and I are Getrag designs and G, H and K are ZF designs. The most common names in US cars are GS6-17BG (Getrag I), GS6-37BZ (ZF H), GS6-45BZ (ZF K), GS6-53BZ (ZF G) and, in the older V8 and M cars, S6S 420G (Getrag D).

The gearboxes took three different lifetime oils over the years, MTF LT-2, LT-3 and LT-5, so the gearbox name alone does not tell you the fluid. This page gives BMW's assignment where its documents show one and says so where they do not.

Quick read

• Ownership position: Not established yet. We are still researching how these gearboxes age in service.
• Reliability: No family-wide verdict. BMW documents in our files cover only the S6S 420G, listed below.
• Cost to own: Not established yet.
• Power potential: Not established yet.
• Main watch item: Fluid grade. BMW moved the GS6-37BZ and GS6-53BZ from MTF LT-2 to MTF LT-3 from 03/2007 production, and lists MTF LT-5 for the GS6-45BZ class of car.

Six-Speed Manuals At a Glance

Technical Specifications

Which BMWs Have Them

Variants

• GS6-17BG (Getrag I): the lighter gearbox, in the N51, N52, N20 and B46 four- and six-cylinder cars. BMW also lists a GS6-17EG with the B46 in the 230i, 330i and 430i.
• GS6-37BZ (ZF H): the mid-size ZF, in the N52, N55 and M54 330i, 530i, Z4 and X3 and X5 cars, with a GS6X-37BZ for the xi cars.
• GS6-45BZ (ZF K): in the N55 and B58 335i, 340i, 435i, 440i, M235i and the M2, and with the S55 in the M2 Competition and the manual F80 M3 and F82 and F83 M4, with GS6X-45BZ for the xDrive cars.
• GS6-53BZ (ZF G): the heavier gearbox, in the N54 335i, the N62 and N63 V8 cars and the S65 E9x M3.
• S6S 420G (Getrag D) and S6S 560G (Getrag E): the older six-speeds. S6S 420G is in the E34 and E39 540i, E39 M5, E46 M3 and Z8; S6S 560G is in the E31 850Ci and 850CSi.

Fluid by Gearbox

BMW's table covers manual gearboxes built after 09/1997; for an older gearbox, such as an E34 540i six-speed, check the label near the filler plug. For the GS6-45BZ, the BMW bulletin table lists the gearbox but its cell is not readable in our copy. BMW parts data lists MTF LT-5 for 335i-class cars, M2, M3 and M4, so that is what we show. Confirm it against the oil filler plug label, which BMW says is yellow for LT-1, green for LT-2 and blue for LT-3.

Service Parts at a Glance

These BMW part numbers were looked up in BMW parts data (December 2019 data date).

Known Failure Points and Service Items

Only items a BMW document backs are listed. We found no BMW bulletin on the GS6-17BG, GS6-37BZ, GS6-45BZ or GS6-53BZ in our files, and an NHTSA recall search on sample US model years found no recall with the manual gearbox as the component. Frequency is not established.

01 Hard shift from third gear, S6S 420G (E39 540i and M5)

BMW service information traces a stiff shift out of third gear to the detent balls on the third-gear selector rod losing their guide. It covers the E39 M5 and 540i with the S6S 420G built from the start of production until 12/1999. BMW's remedy is to replace the arrester balls with arrester sleeves, using repair kit 23 31 7 506 947. Watch for a stiff shift out of third.

02 Leaking drain plug, S6S 420G (E39 540i and M5)

BMW service information says the thread flanks on some drain and filler plugs were not made correctly, so oil could drip from the drain plug. For the S6S 420G it covers the E39 M5 and 540i built between January 1999 and January 2000. BMW's measure is to replace both plugs and renew the lifetime oil. Watch for oil drops at the drain plug.

Reliability Verdict

Not established yet. We are still researching this gearbox family.

Power Potential

Not established yet.

Cost of Ownership

Not established yet.

Common Questions

What manual transmission does a BMW E90 335i have?

BMW parts data lists the ZF GS6-53BZ with the N54 engine, and the GS6-45BZ or GS6-37BZ with the 2010 to 2011 N55 engine. The xDrive 335xi cars carry the GS6X versions.

What manual transmission does a BMW E46 M3 have?

BMW parts data lists the Getrag S6S 420G, the Getrag D gearbox, for the E46 M3 with the S54 engine, with a fill of 1.8 liters.

What oil does a BMW six-speed manual take?

BMW lists lifetime MTF LT-2 for the S6S 420G, MTF LT-2 or LT-3 for the GS6-37BZ and GS6-53BZ depending on production date, and MTF LT-3 for the GS6-17BG. BMW part numbers are 83 22 2 339 219 for LT-2 and 83 22 2 339 221 for LT-3.

How much oil does a GS6-37BZ hold?

BMW technical data gives 1.5 liters, or 1.6 liters on a first fill or replacement gearbox, and BMW parts data gives 1.6 liters.

What does GS6-37BZ mean?

G is for gearbox, S is manual, 6 is six forward gears, 37 is the ZF H gearbox type, B is the petrol gear set and Z is ZF.

Sources

• BMW service documentation: transmission designations and maker table.
• BMW Service Information SI 23 02 96 (142): manual gearbox oils, enclosures 2 and 9 and the MTF table.
• BMW Service Information 23 02 99 (506) and 00 23 03 01: S6S 420G bulletins.
• BMW technical data: transmission filling capacities, group 23.
• BMW parts catalog data, December 2019 data date: fluid table, fitment and part numbers.