2010 BMW X6 40d E71
Discussion
(this is a boring update, it still doesn't drive - waiting on parts!)
Had some spare power steering fluid so thought I'd give it a change.
Sucked just under a litre out of the reservoir with a pipette - bottom left (green) is the colour of new stuff, bottom right (black) is the existing stuff.
It was disgusting and had suspended black bits in as well (probably adhered to the reservoir and loosened when agitated removing).
From my experience I doubt it'll make a difference to how the steering feels, but I certainly feel better about it.
The car has paddle shifters, but BMWs of this era have an odd arrangement where both paddles do the same thing - pull on *either* side upshifts and push downshifts - which is unlike any other paddle shifter arrangement I know of.
My 335d already came with this fixed, and the simplest solution is just to swap the wires on the left hand side paddle to reverse it. Very important to have paddles working intuitively, when you can't shift out of park after all.
This only applies to the earlier models, later models with the "newer" style paddles work differently IIRC
Airbag detached, trim unscrewed and popped free
And removed - note the X5/X6 has an extra pair of bolts holding the trim to the paddle shifter that means you have to remove the airbag, unlike the E9x where apparently you can wiggle the trim free without it (not that removing the airbag is hard)
Paddle shifter connector removed
"Hinged" flap on the connector opened
You need to swap top/bottom wires, depress the little locking tang on the pin to allow it to be removed
Had some spare power steering fluid so thought I'd give it a change.
Sucked just under a litre out of the reservoir with a pipette - bottom left (green) is the colour of new stuff, bottom right (black) is the existing stuff.
It was disgusting and had suspended black bits in as well (probably adhered to the reservoir and loosened when agitated removing).
From my experience I doubt it'll make a difference to how the steering feels, but I certainly feel better about it.
The car has paddle shifters, but BMWs of this era have an odd arrangement where both paddles do the same thing - pull on *either* side upshifts and push downshifts - which is unlike any other paddle shifter arrangement I know of.
My 335d already came with this fixed, and the simplest solution is just to swap the wires on the left hand side paddle to reverse it. Very important to have paddles working intuitively, when you can't shift out of park after all.
This only applies to the earlier models, later models with the "newer" style paddles work differently IIRC
Airbag detached, trim unscrewed and popped free
And removed - note the X5/X6 has an extra pair of bolts holding the trim to the paddle shifter that means you have to remove the airbag, unlike the E9x where apparently you can wiggle the trim free without it (not that removing the airbag is hard)
Paddle shifter connector removed
"Hinged" flap on the connector opened
You need to swap top/bottom wires, depress the little locking tang on the pin to allow it to be removed
(not a boring update, but it still doesn't drive)
The faults looking electrical, but I don't have the tools to diagnose further (but I probably will have to).
More specifically, it looks like there's a fault on the powertrain CANBUS, but the ISTA test plan basically says "try driving the car, it might go away on it's own".
I checked the gearbox oil level (low fluid would cause these issues) and while the level was fine, the gearbox oil wasn't.
It's on the left, new (admittedly ZF lifeguard 6) fluid is on the right... it's really, really dark. This seemed like a more sensible place to start.
ZF oil service kit ordered
There's very little clearance between the transfer case crossmember and the gearbox sump, making some bolts very awkward. I made a tool (just a cut down torx bit) to do this on the X5 but it's gone missing, so made another
Sump removed
Unfortunately one of the bolts snapped in the gearbox - the threads are open on the other side so I reckon water's got in from the top and corroded it
Drilled it out and the thread was savable which was very, very lucky
Dropped the mechatronics unit
The gearbox oil is very expensive (£20 a litre) so it makes sense to think about anything else at the same time.
On the ZF6, the seals wear and cause issues so I thought I'd see if there was a ZF8 equivalent. Not as much info online about this, but found a seal kit that replaces the seals between the mechatronic unit and gearbox. Not pictured is the clutch B seal that took forever to arrive separately.
I also dropped the transfer case bracket as the mechatronic sleeve would've been very difficult to remove with it in place. So homemade tool was for nothing.
The seal kit came with a new plastic "pressure pipe", but my car already had a metal one. So I swapped just the o-rings over. None of the old stuff looked worn, but was noticeably tighter when re-installing.
Clutch B seal was noticeably more proud than before showing the wear over the years
When I was trying to get a seal kit, the seller recommended that my issue was likely to be the solenoids.
My understanding is that the gearbox has a pressurised oil supply, but the solenoids control where the oil flows - and the oil pressure is what actually shifts mechanically (hydraulically?). The gearbox defaults to park with a big spring, whose resistance must always be counteracted.
The solenoids can be tested with a multimeter, but all tested ok - which makes sense, as if not it's likely I would've had a specific fault code.
Still, the solenoids have their own seals and filters etc, so I splashed out on a new solenoid kit, which includes the parking release valve. Genuine ZF parts, and not very cheap at £260.
These parts took *ages* to arrive, and the whole time the car was parked with the sump and mechatronic unit on the bench. It was slowly dripping out transmission oil. When DIY servicing, the torque converter holds some amount of oil you can't drain, and the kits are sized appropriately.
I suspected it'd need a bigger fill than usual, so did the usual cold fill and then started the car to get the oil pumped around and turned it off again. Straight away a lot more could go in.
The next step is to get the gearbox up to temp while stationary and then the final fill - after waiting ages for the gearbox to warm up, just as I got to put more oil in, it kept taking it and taking it until I had no more oil left!
Another bottle of oil later, repeating the whole filling process, and in total, 7.5L of new oil has gone in.
I did the filling process via ISTA, and as new solenoids the adaptations were reset, too.
It seemed ok when up in the air, but back on the floor and the problems still there unfortunately. Frustrating (and expensive, with over £500 of bits...), but it's good preventative maintenance.
I also got frustrated with my tiny workbench, so while waiting for various parts I made one.
In hindsight, not a good idea when you have an immobile, oversized car taking up the space - you need space to work, space for the new bench, space for the old stuff and I spent a lot of time falling over myself.
Not finished, but together enough I can carry on with the car for now.
Speaking of which, the car is now *covered* in sawdust. So that's another job to deal with.
The faults looking electrical, but I don't have the tools to diagnose further (but I probably will have to).
More specifically, it looks like there's a fault on the powertrain CANBUS, but the ISTA test plan basically says "try driving the car, it might go away on it's own".
I checked the gearbox oil level (low fluid would cause these issues) and while the level was fine, the gearbox oil wasn't.
It's on the left, new (admittedly ZF lifeguard 6) fluid is on the right... it's really, really dark. This seemed like a more sensible place to start.
ZF oil service kit ordered
There's very little clearance between the transfer case crossmember and the gearbox sump, making some bolts very awkward. I made a tool (just a cut down torx bit) to do this on the X5 but it's gone missing, so made another
Sump removed
Unfortunately one of the bolts snapped in the gearbox - the threads are open on the other side so I reckon water's got in from the top and corroded it
Drilled it out and the thread was savable which was very, very lucky
Dropped the mechatronics unit
The gearbox oil is very expensive (£20 a litre) so it makes sense to think about anything else at the same time.
On the ZF6, the seals wear and cause issues so I thought I'd see if there was a ZF8 equivalent. Not as much info online about this, but found a seal kit that replaces the seals between the mechatronic unit and gearbox. Not pictured is the clutch B seal that took forever to arrive separately.
I also dropped the transfer case bracket as the mechatronic sleeve would've been very difficult to remove with it in place. So homemade tool was for nothing.
The seal kit came with a new plastic "pressure pipe", but my car already had a metal one. So I swapped just the o-rings over. None of the old stuff looked worn, but was noticeably tighter when re-installing.
Clutch B seal was noticeably more proud than before showing the wear over the years
When I was trying to get a seal kit, the seller recommended that my issue was likely to be the solenoids.
My understanding is that the gearbox has a pressurised oil supply, but the solenoids control where the oil flows - and the oil pressure is what actually shifts mechanically (hydraulically?). The gearbox defaults to park with a big spring, whose resistance must always be counteracted.
The solenoids can be tested with a multimeter, but all tested ok - which makes sense, as if not it's likely I would've had a specific fault code.
Still, the solenoids have their own seals and filters etc, so I splashed out on a new solenoid kit, which includes the parking release valve. Genuine ZF parts, and not very cheap at £260.
These parts took *ages* to arrive, and the whole time the car was parked with the sump and mechatronic unit on the bench. It was slowly dripping out transmission oil. When DIY servicing, the torque converter holds some amount of oil you can't drain, and the kits are sized appropriately.
I suspected it'd need a bigger fill than usual, so did the usual cold fill and then started the car to get the oil pumped around and turned it off again. Straight away a lot more could go in.
The next step is to get the gearbox up to temp while stationary and then the final fill - after waiting ages for the gearbox to warm up, just as I got to put more oil in, it kept taking it and taking it until I had no more oil left!
Another bottle of oil later, repeating the whole filling process, and in total, 7.5L of new oil has gone in.
I did the filling process via ISTA, and as new solenoids the adaptations were reset, too.
It seemed ok when up in the air, but back on the floor and the problems still there unfortunately. Frustrating (and expensive, with over £500 of bits...), but it's good preventative maintenance.
I also got frustrated with my tiny workbench, so while waiting for various parts I made one.
In hindsight, not a good idea when you have an immobile, oversized car taking up the space - you need space to work, space for the new bench, space for the old stuff and I spent a lot of time falling over myself.
Not finished, but together enough I can carry on with the car for now.
Speaking of which, the car is now *covered* in sawdust. So that's another job to deal with.
Edited by Jakg on Thursday 25th April 14:27
Edited by Jakg on Thursday 25th April 14:29
Edited by Jakg on Thursday 25th April 14:31
Jakg said:
Checked all the pins for voltage and all looks good (but don't have the gear to check CAN).
Jakg said:
The faults looking electrical, but I don't have the tools to diagnose further (but I probably will have to).
The only faults I had were communication faults
It'd had errors between different modules and I'd already checked the obvious joints and connectors, but couldn't see anything - but it was consistently the powertrain CAN network (PT-CAN) with issues.
You can view signals on a CAN network with an oscilloscope, so I bought and one and some super handy backfeeding probes so I could watch the traffic at a module while it was still plugged in.
Engine ECU (DDE)
Specifically (and I'm going to butcher this explanation), the pair of wires send a 1 or 0 with the signals across both CAN lines - CAN-high and CAN-low refers to their "off" voltage, and they drop (or increase) respectively to indicate "on"
This means both lines signals can be checked against each other to validate they are working correctly, including if they are shorted with each other / ground / positive.
You can watch this pattern on an oscilloscope. I was *expecting* intermittent bad signals at a module due to a wiring fault
Unfortunately, the signals were all fine - I checked a couple of places and you can see the pattern clearly.
The last place I checked was the handbrake (it's electric) - it's on the PT-CAN, and there's always been an error about it and it's not worked.
However, they are known to fail and while the seller said it'd been replaced, he also told the recovery driver not to use it so I figured I'd get round to that later.
The connector was broken and held together with a cable tie.
Still, CAN tested fine at the plug, too.
So, at this point I was feeling a bit dejected... every step I'd taken had found problems, but nothing was actually fixed. I resigned myself to a new gearbox.
Edited by Jakg on Thursday 2nd May 10:03
Edited by Jakg on Thursday 2nd May 10:08
Jakg said:
So, at this point I was feeling a bit dejected... every step I'd taken had found problems, but nothing was actually fixed. I resigned myself to a new gearbox.
I really, really didn't want to replace the gearbox (for a start - how on earth was I going to get the car high enough in the garage!).So I tried a couple more steps:
- Reset the DSC module (based on a suggestion)
- Reset the steering angle sensor - this was required after resetting the DSC module, and although I'd already done this, the process seemed... different this time?
- Cleared and rescanned for faults
Stayed in gear, with my foot on the brakes in the air.
This is weird...
Put it back on the ground... and rolled out of the garage without issue.
Quick hose to get rid of all the saw dust
And here it is, not at home in the garage!!!!
So what was wrong?
Anti-climatically, I don't know!
Either:
- The communication fault was a red herring - ISTA does suggest that kind of fault *may* go away when the car is driven, but I obviously wasn't able to test that - so fixated on the fault code
- I failed to calibrate the steering angle sensor properly, after the battery/alternator was replaced
- The plug on the handbrake module wasn't connected properly, and that caused the whole car to enter some kind of limp mode
Now it's fixed and I'm keeping it, I can do all the non-essential jobs. Still no idea if I like it yet, though!
Well done! The “it’s fixed snd I don’t know why” is always a painful one but it has its gears, which is good news. I’m sure there was some CAN or other bus issues causing it to have a fit which you have inadvertently solved. Your troubleshooting was top notch too, reminds me of Eric O @SMA on YouTube.
Well done. You should definately open up a beer and celebrate a job well done.
i had an electrical issues with my Ml55 that took 3 months to solve, and in the end it was a major wire connector behind the dash that had slightly become unseated. I really did fire off the parts gun too 3x ecus, 1 wiring loom, 1x new fuse board and removed the entire dash / interior. I had an issue with the ABS pump before hand so I wrongly thought the issue must be related to that, you never think that there could be two faults, which is what I had.
Anyway, you know your car far better now, and if you can check for CAM bus traffic ( I had to do the same ) , replace a gearbox, then you can do anything :-)
Enjoy the truck.
simon
i had an electrical issues with my Ml55 that took 3 months to solve, and in the end it was a major wire connector behind the dash that had slightly become unseated. I really did fire off the parts gun too 3x ecus, 1 wiring loom, 1x new fuse board and removed the entire dash / interior. I had an issue with the ABS pump before hand so I wrongly thought the issue must be related to that, you never think that there could be two faults, which is what I had.
Anyway, you know your car far better now, and if you can check for CAM bus traffic ( I had to do the same ) , replace a gearbox, then you can do anything :-)
Enjoy the truck.
simon
Watchthis said:
Where did you purchase the zf8 solenoids and seals from?
Solenoids - https://www.autodoc.co.uk/zf-getriebe/15816662 - for reference, I paid £260 - the prices change daily so if it's expensive today, try again tomorrowSeal kit - https://www.sussexautos.com/products/8hp45-8hp70-m...
Clutch B seal - https://www.ic24.uk/products/f826a2-automatic-gear... - took about 2 weeks to arrive from Poland, but can't argue less than a fiver delivered
Jakg said:
Solenoids - https://www.autodoc.co.uk/zf-getriebe/15816662 - for reference, I paid £260 - the prices change daily so if it's expensive today, try again tomorrow
Seal kit - https://www.sussexautos.com/products/8hp45-8hp70-m...
Clutch B seal - https://www.ic24.uk/products/f826a2-automatic-gear... - took about 2 weeks to arrive from Poland, but can't argue less than a fiver delivered
Fantastic, thanks for the info. I've got the oil and filter kit for mine but wouldn't mind swapping the solenoids and seals whilst I'm under thereSeal kit - https://www.sussexautos.com/products/8hp45-8hp70-m...
Clutch B seal - https://www.ic24.uk/products/f826a2-automatic-gear... - took about 2 weeks to arrive from Poland, but can't argue less than a fiver delivered
I've always liked the X6 shape even though I generally dislike SUVs. Colour looks great on it too - even though it's subtle as you say, it's a lovely shade of silver and you can tell it's more 'special' than regular silver.
I hope after all your efforts you like the car and get to enjoy it for a bit!
I hope after all your efforts you like the car and get to enjoy it for a bit!
Jakg said:
The last place I checked was the handbrake (it's electric) - it's on the PT-CAN, and there's always been an error about it and it's not worked.
However, they are known to fail and while the seller said it'd been replaced, he also told the recovery driver not to use it so I figured I'd get round to that later.
The connector was broken and held together with a cable tie.
Luckily available separately (...for £16...), good as new.However, they are known to fail and while the seller said it'd been replaced, he also told the recovery driver not to use it so I figured I'd get round to that later.
The connector was broken and held together with a cable tie.
Clocked up some miles now and, touch wood, no gearbox issues.
First impressions are:
I think for most people (including myself) the X5 is probably a better (and cheaper) option, which I already knew!
I'm also still £2k up on the cheapest X6 40d for sale right now (ignoring tools and labour), which is nice.
Another not-in-the-garage shot
I now have three cars with identical keys, which is absolutely infuriating
First impressions are:
- despite being an X5 underneath, it feel more like a car than an SUV to drive. I think it's the much smaller windscreen that tricks your brain. I'm not sure this is actually a good thing!
- the gearbox (8HP) is much better than the older 6HP in my 335d/X5
- the steering is unpleasantly light, with no feel. Maybe I'll adjust?
- ride over rough surfaces so much better than my 335d
- black seats, black leather, black headlining, black trim with a small sunroof (no pan roof on X6!) means it feels a little dark inside
- wing mirror cameras make it very easy to park
I think for most people (including myself) the X5 is probably a better (and cheaper) option, which I already knew!
I'm also still £2k up on the cheapest X6 40d for sale right now (ignoring tools and labour), which is nice.
Another not-in-the-garage shot
I now have three cars with identical keys, which is absolutely infuriating
Edited by Jakg on Wednesday 8th May 11:45
Love it. Had an E71 40d myself for 3 years. Chopped it in for an X6M F86 and regretted it almost immediately. Hated the M and got rid within 6 months. Currently in an F82 M4 but I keep scouring the ads for a petrol E71 with the right spec.
Yours looks almost perfect. I say almost, as I had the roof bars on mine which came in useful
Yours looks almost perfect. I say almost, as I had the roof bars on mine which came in useful
Jakg said:
Clocked up some miles now and, touch wood, no gearbox issues.
First impressions are:
I think for most people (including myself) the X5 is probably a better (and cheaper) option, which I already knew!
I'm also still £2k up on the cheapest X6 40d for sale right now (ignoring tools and labour), which is nice.
Another not-in-the-garage shot
I now have three cars with identical keys, which is absolutely infuriating
Good to see it's out & about in the wild First impressions are:
- despite being an X5 underneath, it feel more like a car than an SUV to drive. I think it's the much smaller windscreen that tricks your brain. I'm not sure this is actually a good thing!
- the gearbox (8HP) is much better than the older 6HP in my 335d/X5
- the steering is unpleasantly light, with no feel. Maybe I'll adjust?
- ride over rough surfaces so much better than my 335d
- black seats, black leather, black headlining, black trim with a small sunroof (no pan roof on X6!) means it feels a little dark inside
- wing mirror cameras make it very easy to park
I think for most people (including myself) the X5 is probably a better (and cheaper) option, which I already knew!
I'm also still £2k up on the cheapest X6 40d for sale right now (ignoring tools and labour), which is nice.
Another not-in-the-garage shot
I now have three cars with identical keys, which is absolutely infuriating
Edited by Jakg on Wednesday 8th May 11:45
You could always 're-case' the key so it stands out more: https://www.ebay.co.uk/itm/204318687658?fits=Car+M...
Something like that for example
Fas1975 said:
Love it. Had an E71 40d myself for 3 years. Chopped it in for an X6M F86 and regretted it almost immediately.
Interested to know what you didn't like about the M - I was originally after an E71 X6M but there was a big variation in prices.Fas1975 said:
I keep scouring the ads for a petrol E71 with the right spec.
Petrol makes way more sense for my usage profile, but there were barely any for sale and at stupid prices.d_a_n1979 said:
You could always 're-case' the key so it stands out more: https://www.ebay.co.uk/itm/204318687658?fits=Car+M...
Not sure that'll work, it's not keyless and there's a tight slot for the key to sit in. I did think about a cover for the key but decided against it for that reason.There's some animal stickers in the post right now...
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