Driveline Service (X6 40d)
Posted: Mon Dec 20, 2021 6:01 pm
Took my X6 in for a full driveline service this morning. For the initiated this is both diffs, transfer and gear boxes. ZF recommend it every 8 yrs or 50,000 miles. BMW regard the transmission as being end of life after 3 years and as it’s filled with ‘Lifetime Oil’ hence they don’t service it. ZF think otherwise, and given they design and build it……..
The car is 11 years old and just passed 53k miles so due on both age and mileage (not that my BMW Dealer showed any interest, or even offered a service of this type).
Got the car back this evening and the gearbox is as smooth as silk again. I had noticed a very slight ‘nudge’ when it changed down but that has gone completely.
Not a cheap job, but the E71 variant has (alongside the X6M and X5M) a clever GKN/ZF made Torque Vectoring rear differential. This is an electro-hydraulic unit with powered clutches on each output shaft. It has 3 chambers and two different oils (it would wouldn’t it!). The oil alone for the rear diff side chambers is £122 (£61/litre). The centre chamber uses the same as the front diff.
All in, including all labour, parts, oils, new pan (inc filter) and bolts (these MUST be changed) it came to £880 inc VAT. Labour was £288 of that. This was done by a Specialist BMW Indy in Milton Keynes. They also reset the transmission adaptations in the EGS module. This last bit is necessary to ensure the internal solenoid pressure values are reset using a specific ZF ‘relearning’ procedure. If the retuned values are too high then there is an internal issue with the box - meaning a rebuild is on the cards.
Still well under the £1,200 I was quoted by a ZF ‘aftermarket’ centre, and that was just to service the gearbox! I dread to think what a main BMW Dealer would have charged - if they offered such a service. Stupid really because the rear diff side-chamber oil had to come from them anyway.
The car is 11 years old and just passed 53k miles so due on both age and mileage (not that my BMW Dealer showed any interest, or even offered a service of this type).
Got the car back this evening and the gearbox is as smooth as silk again. I had noticed a very slight ‘nudge’ when it changed down but that has gone completely.
Not a cheap job, but the E71 variant has (alongside the X6M and X5M) a clever GKN/ZF made Torque Vectoring rear differential. This is an electro-hydraulic unit with powered clutches on each output shaft. It has 3 chambers and two different oils (it would wouldn’t it!). The oil alone for the rear diff side chambers is £122 (£61/litre). The centre chamber uses the same as the front diff.
All in, including all labour, parts, oils, new pan (inc filter) and bolts (these MUST be changed) it came to £880 inc VAT. Labour was £288 of that. This was done by a Specialist BMW Indy in Milton Keynes. They also reset the transmission adaptations in the EGS module. This last bit is necessary to ensure the internal solenoid pressure values are reset using a specific ZF ‘relearning’ procedure. If the retuned values are too high then there is an internal issue with the box - meaning a rebuild is on the cards.
Still well under the £1,200 I was quoted by a ZF ‘aftermarket’ centre, and that was just to service the gearbox! I dread to think what a main BMW Dealer would have charged - if they offered such a service. Stupid really because the rear diff side-chamber oil had to come from them anyway.
2 different oils in the diff , well who needs that complexity ? lol 
