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D4 - Transmission Gearboxes, diffs, drive shafts.

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  #11  
Old 20th August 2016, 01:28 PM
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Quote:
Originally Posted by paulrstaylor View Post
It's an eight-speed auto, believe it is a ZF-8HP box.

https://en.wikipedia.org/wiki/ZF_8HP_transmission
Thanks for that Paul. The GPS anticipating downshifts will speed things up, but the big improvement over the D3 box appears to be much faster changes. One of my D3 gripes is the tardy downshifts.
That Wiki is a little in error in that BMW do fit DSG boxes to some models, and they are soooo good
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  #12  
Old 21st August 2016, 07:53 AM
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I seem to remember that when i first tested a D4 4.2 Tdi with the 8 speed box I found it to be very smooth and almost impossible to tell when it changed gears! LINK to Thread
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  #13  
Old 26th August 2016, 06:53 PM
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Quote:
Originally Posted by Joe2.0E View Post
My 2011 3.0TDI can be quite rough when cold, most noticeable when selecting reverse. I have had the ATF changed and it didnt make any difference.
By comparison my old 6 speed D3 was smoother when cold but nothing as "Clever" in terms of seamless/fast changes you get on the D4.
thanks for reply guys, my Gmail app wasn't updating emails and I thought nobody reply.

like Joe2 I do experience rough changes when cold, I had ATF changed, but before I did that I had new software updated by audi. I'm thinking to do one more time ATF change and maybe ask Audi to do adaptation, reset everything in transmission ecu. so basically transmission will start learning from beginning. Or maybe someone on this forum knows how to do that through Vcds?

question to Joe2 - do you know what type ATF did garage use when they changed for you? my used according to specification by manufacturer but I think they should use proper ZF lifeguard 8. Next time I will use that one.
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  #14  
Old 26th August 2016, 07:07 PM
Joe2.0E Joe2.0E is offline
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I used my local Audi Dealer to do the ATF change and they used the Audi branded ATF fluid. I'll check the part no.s from the invoice and update the thread when I have them to hand.
It would appear to be a common issue with the 8 speed ZF box on F10 BMW's if you have a look on some Beemer forums.
The ATF change made no obvious difference with my car but overall its still a fantastic autobox. I suspect the issue may be software related rather than an issue with the ATF.
Unless it gets worse, I'm not too concerned.
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  #15  
Old 26th August 2016, 07:47 PM
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Quote:
Originally Posted by Joe2.0E View Post
I used my local Audi Dealer to do the ATF change and they used the Audi branded ATF fluid. I'll check the part no.s from the invoice and update the thread when I have them to hand.
It would appear to be a common issue with the 8 speed ZF box on F10 BMW's if you have a look on some Beemer forums.
The ATF change made no obvious difference with my car but overall its still a fantastic autobox. I suspect the issue may be software related rather than an issue with the ATF.
Unless it gets worse, I'm not too concerned.

i agree it is still fantastic gearbox, just this issue when cold. as you mentioned BMW users are complaining too, I found actually thread about 1 series but if you say f10 has issue as well then I will not worry so much. also as you said ATF change didn't cure it, so I also think it is more software related. over 60k miles on mine
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  #16  
Old 2nd May 2018, 02:03 PM
GlynH GlynH is offline
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Sorry for resurrecting an old thread but reading posts on here it seems that the 'box fitted to the D4 is the ZF 8HP55?

Looking on Wikipedia at the entry for this very box it lists the maximum petrol/diesel torque for the various 8HP gearboxes but something can't be right here surely?

https://en.wikipedia.org/wiki/ZF_8HP...F_8HP_variants

Looking down the page at the list of ZF 8HP Variants it lists the 8HP55 as being fitted to the A8/A8L D4 along with Q5/Q7 but looking at the maximum torque of 550Nm is wrong surely?

My 2011 pre-facelift D4 produced a standard 800Nm and the 2014 Facelift generates 850Nm of torque which is way above the maximum torque limit listed!

My 2011 was remapped to give 415BHP and 966Nm of torque and a couple of friends of mine have had their S8's remapped to 668BHP/945Nm and 705BHP/1014Nm respectively.

Here's hoping that the torque values listed on Wiki are just plain wrong...

Or am I overthinking things again...

-=Glyn=-
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  #17  
Old 2nd May 2018, 07:38 PM
Joe2.0E Joe2.0E is offline
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You might be on to something, I don't think it's going to be the best in terms of longevity.
My 2011 3.0TDI developed a whine in reverse about a year ago. Had the ATF changed but it didn't make any difference.
Common enough on F10 BMW's that use a variation of the same ZF 8HP unit.
Anyone else got the same issue ?
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  #18  
Old 2nd May 2018, 09:27 PM
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4.2 tdi's have 8hp90a which is good to 1000nm!!
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  #19  
Old 3rd May 2018, 01:43 PM
damtom85 damtom85 is offline
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Yes 3.0tdi which has just over 500Nm has 8hp55 but 4.2 tdi has 8hp90, audi also uses 8hp70. Different number after 8hp means different maximum torque
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