Auto "kicking down" when descending hills

4687ah · Post by **4687ah** » Wed Jul 18, 2012 9:19 pm

Hi, as I have said before I am new to autos, so be gentle! I have twice noticed the x dropping down the gears very noticeably when i touched the brakes going down a steep hill. I was wondering if the car senses a decline and the brake pedal being applied so changes down to assist by engine braking.
This has been on A roads so it's not like a crawling off road incline. The last time it sent the revs up to about 3500 to 4000rpm (it's a diesel) and for the incline and road speed this seemed severe.
Is this the norm or a bit unusual? Anyone else experienced anything similar?
Thank you.

Horizon · Post by **Horizon** » Wed Jul 18, 2012 9:29 pm

Its normal for the X5 to change down and hold a lower gear when decending. The car senses thay you are trying to slow the car with the brakes, so changes down a gear or 2 to aid in engine braking to stop you overheating the brakes. Far too clever. Ive had several BMW autos and the X is the only one to do this.
Lots of past tnhreads on the subject.
There is a gearbox soft reset proceedure to improve matters, im sure one of the regular guys will put a link up for you

Sanj · Post by **Sanj** » Wed Jul 18, 2012 9:31 pm

Normal engine braking, don't worry.

petert · Post by **petert** » Wed Jul 18, 2012 9:36 pm

Normal. Happened (as designed) on my 3.0i petrol version as well, and yes - the rev increase felt rather harsh to me as well.
Peter T

X5Sport · Post by **X5Sport** » Wed Jul 18, 2012 9:53 pm

It's the special BMW/ZF 'cringe' or 'wince' function....immediately replaced by the 'moment of panic' function when you then apply throttle and the car is off like a scared rabbit once the engine braking disconnects. :drive:

I love the German sense of humour......

)

barnowl930 · Post by **barnowl930** » Wed Jul 18, 2012 10:06 pm

Turn off the DSC, this stops that and it turns into waftamatic.

The bloke that wrote the software for the x5/zf 6hp26 was a d%*khead. imho

shadrack · Post by **shadrack** » Wed Jul 18, 2012 10:09 pm

[quote="barnowl930"]
Turn off the DSC, this stops that and it turns into waftamatic.

The bloke that wrote the software for the x5/zf 6hp26 was a d%*khead. imho
[/quote]
i do this or drive in manual mode alot round where i am as its very hilly and tbh its embarrasing when your going down a hill and its reving itself so high

4687ah · Post by **4687ah** » Wed Jul 18, 2012 10:16 pm

It made sense, it just seemed a bit severe but if it's quite normal then that's me sleeping tonight. It doesn't help that I do so many miles in my van so am used to that and don't get much chance to get familiar with the car.
May try that software reset, just out of interest really.
Thanks to all for the reassuring replies.

CondorX5 · Post by **CondorX5** » Wed Jul 18, 2012 10:57 pm

Mine does it as well, a bit disconcerting at times.......then flies off like a bat out of hell but with a very loud V8 growl instead of a hgh pitched batlike

scooby1doo1 · Post by **scooby1doo1** » Thu Jul 19, 2012 12:26 am

As others mine does this, but never revved that high. Only drops one gear and only if I lightly touch the brakes.
My 530d did this as well and that only dropped one gear, i think it's a good idea saves ridding the brakes if your going down a long hill.

Sent from the Iphone via talktapa

Cannondale · Post by **Cannondale** » Thu Jul 19, 2012 6:48 am

[quote="scooby1doo1"]
As others mine does this, but never revved that high. Only drops one gear and only if I lightly touch the brakes.
My 530d did this as well and that only dropped one gear, i think it's a good idea saves ridding the brakes if your going down a long hill.

Sent from the Iphone via talktapa
[/quote]

Mine is exactly the same, it seems to change down as I wouod have in a manual car. No big revs and as soon as you go back on the power it change straight back up.

Are there diffrent softwear versions for the gearbox?

Rich...

X5Sport · Post by **X5Sport** » Thu Jul 19, 2012 10:30 am

[quote="Cannondale"]

Are there diffrent softwear versions for the gearbox?

Rich...
[/quote]
Yes indeedy.....probably two or three versions released for the X5, but usually only uploaded if there's an issue. They're really only patches to fix known problems, or if like me you have a new Mechatronics module which needs to be 'taught' which car it's going into (they're blank when new).

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