BMW TRANSMISSION & DIFFERENTIAL OIL

BMW TRANSMISSION & DIFFERENTIAL OIL

John Iuga

 This page covers fluid information and recommendations for BMW manual and automatic transmissions, rear differentials, and front differentials on xDrive models. Note: for the purposes of this page, "Vintage" refers to all BMW cars built up to and including the E30 3-series.

BMW Manual / SMG / DCT Transmission Fluid 


Vintage 5-speed manual
Most manual transmissions on vintage models do not have a fluid label on the transmission because nearly all gearboxes took the same fluid - a universal GL-4.  If no label is present, the official recommendation is any GL-4 gear oil. Our favorite is the Red Line MTL. However, some transmissions will have an orange ATF label and you should use a Dexron III ATF fluid. The 1984-1986 325e/528e should have a green "Special Oil" label on the transmission. These transmissions use a specific Mobil SHC 630 synthetic fluid (SAE 90 weight). Because of the narrow applications, we don't have a recommended alternative to the Mobil fluid.
Recommended replacement interval: 30,000-40,000 miles

Shop MTL for BMW Manual Transmissions:

MTL 75W80 GL-4 Gear Oil

Red Line MTL


1990s-2000s 5-speed and 6-speed ATF (excluding E46 M3, E9X M3, Z4M)
 

From the mid-1990s, nearly all BMW manual transmissions, except 6-speed M models, use a Dexron III ATF oil, indicated by an "ATF" label on the transmission. You can find a Dexron III spec almost anywhere, but we are impressed with the performance of Red Line ATF D4 in manual transmissions. In our experience, it outperforms even fresh factory fluid, especially in colder temps. For track use, an ATF may become too slippery at high temps, in which case we recommend the Red Line MT-LV which has a slightly heavier weight that holds up better.
Recommended replacement interval: 30,000-40,000 miles

Shop ATF for BMW Manual Transmissions:

D4 ATF

Red Line D4 ATF


This is the era that BMW started using "Lifetime" fluids, indicated by a "MTF" label on the transmission. The "Lifetime" has never been fully explained and we don't buy into it, especially when fresh fluid typically makes a huge improvement in shift quality and smoothness. The fluid formula has changed over the years - MTF-LT-1, LT-2, LT-3, LT-5, and FFL-4. There are discernible differences between them and LT-2 has the strongest following among enthusiasts. Our observations are that these LT fluids are acceptable in normal day-to-day driving and in cold temperatures but are permanently affected by high temps, such as on track. We have found that the Red Line MT-LV is superior than ATF D4 and factory MTF for these cars in all conditions. SMG transmissions use the same MTF oil as the manual transmissions, however, the SMG Hydraulic Pump uses Pentosin CHF 11S hydraulic fluid.2000s-2010s M 6-speed and SMG (not DCT) MTF

Recommended replacement interval: 30,000-40,000 miles

Shop MTF for BMW Manual Transmissions:

Red Line MT-LV

2000s-2010s DCT
The Double-Clutch transmission uses a set of two clutches that are "wet" clutches. The clutch discs are immersed in the same oil used to lubricate the transmission internals. The wet clutch system ensures smooth operation and engagement. BMW requires a special DCT-specific fluid, although they also label it as "Lifetime Fill". We don't buy in to the lifetime fluid policy and have experienced the benefits of fresh fluid on our daily and track cars.

The OEM DCT fluid is made by Pentosin and works just fine for normal street use. Red Line DCTF is an upgraded formula that works on normal street cars and holds up better for sustained track time. With more power or higher heat the fluid thins out and breaks down which causes the clutches to slip. A stronger oil like the Red Line fluid will not break down as easily at higher temps.
Recommended replacement interval: 30,000-40,000 miles

Shop DCTF for BMW:

Dual Clutch Transmission Fluid

Red Line DCTF


 

BMW Automatic Transmission Fluid

Note that changing the fluid on automatic transmissions can be a very technical process that requires a precise procedure, special tools, and/or professional-level diagnostics software. There is no doubt that fresh fluid will perform better than used and dirty fluid. However, most of the problems we hear come from an improper transmission flush where particles and debris block fluid flow or from failing to set the correct fluid level after. We believe automatic transmission fluid service should be left to a professional BMW technician and that extended fluid service (>50,000 miles) is acceptable as long as the fluid level is regularly checked and maintained.

Vintage 4-speed auto
ATF Dexron III is the fluid standard for 4-speed BMW automatics (ZF 4HP). This is also the most common ATF you will find at auto parts stores (it's compatible with most GM and Ford auto transmissions).
Recommended replacement interval: 40,000 miles

Shop ATF for BMW Automatic Transmissions:

D4 ATF

Red Line D4 ATF

1990s-2000s 4- & 5-speed auto
BMW 4 and 5-speed automatics are made by either ZF (4HP) or GM (5L40-E/A5S360R). The recommended ATF for either is Dexron III (D4). This is also the most common ATF you will find at auto parts stores (it's compatible with most GM and Ford auto transmissions). BMW has transitioned to a newer Dexron VI spec, which is backwards compatible with Dexron III. If your car is serviced at the dealer they will likely install D6. BMW recommends using only the same fluid in the transmission when topping off the oil level. They do not recommend mixing ATF oil brands and specs so keep track of what oil is in your transmission.
Recommended replacement interval: 60,000 miles

Shop ATF for BMW Automatic Transmissions:

D4 ATF

Red Line D4 ATF

All 6-speed auto
The BMW 6-speed automatic is made by either GM (6L45/6L50) or ZF and was used mostly in mid-2000s RWD and AWD models. BMW used the ZF GA6HP19, GA6HP26, and GA6HP28 throughout the model range. Contrary to what's written online, the ZF 6HP can be serviced with a full oil pan and gasket kit available. However, professional servicing is recommended due to the precise procedures required. The OEM ATF is a ZF Lifeguard 6 which carries a Dexron VI (D6) rating. BMW refers to it as "ATF 2". Cars that originally used D6 cannot use D4 (all 6- and 8-speed automatics) so keep track of what oil is in your transmission.
Recommended replacement interval: 80,000 miles (BMW's estimate is 100,000 miles)

Shop ATF for BMW 6-speed Automatic Transmissions:

D6 ATF

Red Line D6 ATF

All 8-speed auto
The BMW 8-speed automatic is made by ZF and was used mostly in mid-2010s RWD and AWD models. BMW used the 8HP45, 8HP50, 8HP70, 8HP75 throughout the model range. The ZF 8HP can be serviced with a full oil pan and gasket kit available. However, professional servicing is recommended due to the precise procedures required. The OEM ATF is a ZF Lifeguard 8 which carries a Dexron VI (D6) rating. BMW refers to it as "ATF 3". Cars that originally used D6 cannot use D4 (all 6- and 8-speed automatics) so keep track of what oil is in your transmission.
Recommended replacement interval: 80,000 miles (BMW's estimate is 100,000 miles)

Shop ATF for BMW 8-speed Automatic Transmissions:

D6 ATF

Red Line D6 ATF


 

BMW xDrive Front Differential and Transfer Case Fluid

BMW Xi and xDrive models use a center transfer case to distribute power to the rear and front axles. This is a chain-driven transfer case mounted on the back of the transmission with a driveshaft extending from the front and rear of the housing. The front differential is a traditional hypoid gear design very similar to the rear differential but in a smaller size.

Center Transfer Case
1999-2003 325Xi/330xi and X5 Models (NV Transfer Case)
BMW recommendation: ATF Dexron III rated
Our recommendation: Red Line D4 ATF
Recommended replacement interval: 50,000-60,000 miles

Shop ATF Transfer Case Oil:

D4 ATF

Red Line D4 ATF

All Front Differential
BMW recommendation: SAF-XO, 75W90 weight, GL-5 rated
Our recommendation: Red Line 75W90
Recommended replacement interval: 40,000-50,000 miles

Shop Front Axle Gear Oil:

75W90 GL-5 Gear Oil

Red Line 75W90


 

BMW Rear Differential Gear Oil

BMW rear differentials are either open without a limited-slip feature or with limited-slip (posi-traction). Nearly all non-M models use an open differential and rely on traction control to limit wheel spin. Vintage models and M cars use some form of limited-slip - clutch-type, viscous, or Torsen designs.

Vintage-1990s Open or Limited-Slip Differential
BMW recommendation: SAF-XJ, 75W140, GL-5 rated*
Our recommendation: Red Line 75W90 or 75W110
Recommended replacement interval: 40,000-50,000 miles

* - The SAF-XJ synthetic fluid replaces the previous factory recommendation of SAF-XLS mineral oil for clutch-type limited-slip differentials. This must have been part of a larger effort to switch to full synthetic instead of mineral-based oils. The 75W140 weight is strange to us but it's the only gear oil listed in BMW's official fluid guide for these differentials. We have used Red Line 75W90 in just about everything with great results and have adopted the new 75W110 for hot climates or heavy track use.

Shop 75W90 Rear Axle Gear Oil: 

                                                                                                                            75W90 GL-5 Gear Oil                                                    75W110 GL-5 Gear Oil      

                                                                                                                            Red Line 75W90                                                  Red Line 75W110    

Rear Open Differential, before 7/2011 production
BMW recommendation: SAF-XO, 75W90 weight, GL-5 rated
Our recommendation: Red Line 75W90
Recommended replacement interval: 40,000-50,000 miles

Shop SAF-XO Rear Axle Gear Oil:

                                                                                                                            75W90 GL-5 Gear Oil                                                    75W110 GL-5 Gear Oil      

                                                                                                                            Red Line 75W90                                                  Red Line 75W110    

Rear Open Differential, after 7/2011 production
BMW recommendation: G1 synthetic, 75W85 weight, GL-4 rated
Our recommendation: Red Line MT-85 (GL-4)
Recommended replacement interval: 40,000-50,000 miles

Shop G1 Rear Axle Gear Oil:

MT-85 75W85 GL-4 Gear Oil

Red Line MT-85

Rear 2001-2013 M-Variable Limited-Slip Differential
BMW recommendation: SAF-XJ+FM, 75W140, GL-5 rated
Our recommendation: Red Line 75W140
Recommended replacement interval: 40,000-50,000 miles

Shop M-Variable Diff Oil:

75W140 GL-5 Gear Oil

Red Line 75W140

Rear 2012-present M-Active Electronic Limited-Slip Differential
BMW recommendation: MSP/A 75W140, GL-5 rated
Our recommendation: Red Line 75W140
Recommended replacement interval: 40,000-50,000 miles

Shop M-Active Diff Oil:

75W140 GL-5 Gear Oil

Red Line 75W140

Rear M Performance Limited-Slip Differential (F22, F30, F32, etc)
BMW recommendation: hard to say because BMW does not publish a replacement fluid. We think it's MSP/A 75W140 (same as used in M Active diffs).
Our recommendation: Red Line 75W90 or 75W110
Recommended replacement interval: 40,000-50,000 miles

Shop M Performance Diff Gear Oil:

                                                                                                                            75W140 GL-5 Gear Oil                                                    75W110 GL-5 Gear Oil      

                                                                                                                            Red Line 75W90                                                  Red Line 75W110    

 

Rear Custom Differential
Through our friends and diff experts at Diffsonline, we offer custom-built performance differentials. These diffs are usually built with some form of a limited-slip feature, using traditional clutch discs, a viscous unit, or helical gears. Below you will find fluid recommendations for each.
Recommended replacement interval: 40,000-50,000 miles
Traditional clutch-type: Red Line 75W90 for moderate street use; Red Line 75W110 for aggressive street and/or track
Factory BMW M Variable: Castrol-BMW SAF XJ+FM or Red Line 75W140
Diffsonline Helical: Red Line 75W110
Quaife: Red Line 75W110
Wavetrac: Red Line 75W110
OS Giken: proprietary OS Giken-branded 85W250
Kaaz: proprietary Kaaz fluid

Shop Custom Diff Gear Oil:

                                                                                          75W110 GL-5 Gear Oil                                                    75W110 GL-5 Gear Oil                                                    75W140 GL-5 Gear Oil

                                                                                         Red Line 75W90                                                  Red Line 75W110                                                Red Line 75W140    

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Terminology & Acronyms
Below are some explanation of the scientific terminology, jargon, and acronyms commonly used when discussing BMW transmission and differential axle fluid.

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