Not joined yet? Register for free and enjoy features such as alerts, private messaging and viewing latest posts and topics.

How long are DCT boxes designed to last?

Specific discussion about the E89 2009 Z4 (sDrive35is, sDrive35i, sDrive30i, sDrive23i)
User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

How long are DCT boxes designed to last?

Post by sunnydays » Mon Dec 04, 2017 5:13 pm

BMW states the DCT will last the life of the car, does this mean mileage wise or years?

Additionally I noticed the 35i and 35is use the Getrag GS7-D36SG. This is the same part # as the E92 M3 4.0 and i beleive the 335i, 135i m and m4 also use this. Are these literally identical? Ie could a m3 dct box be dropped in to a z4 for example

Thanks

User avatar
Zed Five
Senior Member
Senior Member
Posts: 2290
Joined: Thu Aug 20, 2009 1:58 pm

How long are DCT boxes designed to last?

Post by Zed Five » Mon Dec 04, 2017 5:16 pm

Why, do you have a problem with yours? Age will be irrelevant, how it is used and how much will be.
Why is it that people who can't take advice always insist on giving it? 

E89 35is | BMW S1000rr Motorsport Ed.

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

How long are DCT boxes designed to last?

Post by sunnydays » Mon Dec 04, 2017 5:23 pm

Zed Five wrote: Mon Dec 04, 2017 5:16 pm Why, do you have a problem with yours? Age will be irrelevant, how it is used and how much will be.
Nah I dont, just thinking longer term ownership and part availabillity

User avatar
Gaffa22
Member
Member
Posts: 407
Joined: Wed Aug 16, 2017 9:31 am

How long are DCT boxes designed to last?

Post by Gaffa22 » Mon Dec 04, 2017 6:54 pm

Well hopefully they will last a bloody long while, you can't get bits for them and they are about £9000 to replace.
However they are manufactured to withstand 600bhp plus and are regarded as being very reliable, so fingers crossed eh !
2010 E89 35i DCT
2017 Honda CBR1000RR fireblade
2016 Honda VFR1200F
Image

Scooba_Steve
Lifer
Lifer
Posts: 5277
Joined: Wed Feb 19, 2014 3:01 pm
Location: NW London

How long are DCT boxes designed to last?

Post by Scooba_Steve » Mon Dec 04, 2017 7:15 pm

Are they "lifetime fill"... There's no substitute for mechanical sympathy.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

User avatar
Gaffa22
Member
Member
Posts: 407
Joined: Wed Aug 16, 2017 9:31 am

How long are DCT boxes designed to last?

Post by Gaffa22 » Mon Dec 04, 2017 7:19 pm

Yes BMW state the oil is lifetime, apparently they are not easy to do an oil change on
2010 E89 35i DCT
2017 Honda CBR1000RR fireblade
2016 Honda VFR1200F
Image

Andyturbo2000
Member
Member
Posts: 50
Joined: Sun Sep 10, 2017 10:21 am

How long are DCT boxes designed to last?

Post by Andyturbo2000 » Mon Dec 04, 2017 8:50 pm

Had an Audi S Tronic, most said 100,000 is considered a 'lifetime'. Mine went at 85,000. 10k to fix

flybobbie
Lifer
Lifer
Posts: 4016
Joined: Sat May 25, 2013 8:27 pm
Location: Stourbridge

How long are DCT boxes designed to last?

Post by flybobbie » Mon Dec 04, 2017 9:57 pm

Depends how long a 'life' is, they tend to vary.
One of my customers bought a new Mini in 1970.
Changed oil every 3k, got rid of the car at 230k miles and 23 years later, so he says.

User avatar
sunnydays
Member
Member
Posts: 983
Joined: Fri Sep 23, 2016 7:50 am

How long are DCT boxes designed to last?

Post by sunnydays » Mon Dec 04, 2017 11:48 pm

I guess the real question is could you just take the dct out of say a 335i which also has the n54 and drop it in the z4. Its the same model dct and engine etc.... and these boxes are only around £1000 when they appear on ebay. This is certainly more reassuring if it can be done!

User avatar
R.E92
Senior Member
Senior Member
Posts: 1644
Joined: Wed Dec 04, 2013 10:10 am

How long are DCT boxes designed to last?

Post by R.E92 » Tue Dec 05, 2017 9:37 am

sunnydays wrote: Mon Dec 04, 2017 11:48 pm I guess the real question is could you just take the dct out of say a 335i which also has the n54 and drop it in the z4. Its the same model dct and engine etc.... and these boxes are only around £1000 when they appear on ebay. This is certainly more reassuring if it can be done!
Yes, it's the same unit.

The transmission is the same between the 135i, 335i, Z4 and the M3. The only difference being the M3 has a different gear selection unit (shifter) which means you can't use the M3 software with the other cars. Although some people are working on making that possible.

Scooba_Steve
Lifer
Lifer
Posts: 5277
Joined: Wed Feb 19, 2014 3:01 pm
Location: NW London

How long are DCT boxes designed to last?

Post by Scooba_Steve » Tue Dec 05, 2017 10:19 am

The cynic in me believes that lifetime is really just the warranty period... If you get a second hand box, how do you know it has been looked after, won't fail similarly etc.
3.0si Sport: F10 Illuminated ZHP, Retrofit Cruise, OE Stubby, Gaptech RCH+, Kenwood BT73DAB + Handsfree, HIDs, LED Sidelights, OE LED Number Plate Lights, Custom LED strip bootlight.

Andyturbo2000
Member
Member
Posts: 50
Joined: Sun Sep 10, 2017 10:21 am

How long are DCT boxes designed to last?

Post by Andyturbo2000 » Tue Dec 05, 2017 11:55 am

And warranties are only valid if all the service is complete from the past...that one caught me out

User avatar
stuartinzg
Member
Member
Posts: 838
Joined: Fri Aug 14, 2015 7:33 am

How long are DCT boxes designed to last?

Post by stuartinzg » Tue Dec 05, 2017 1:46 pm

I've been speaking to ken at wedge performance who said he has access to the pressure line tables for the DCT now, through MHD.
They are running 600 whp on stock units and the clutches appear to be holding. He also recommends SSP over Dodson, a lot of issues with Dodson clutches on the BMW DCT, although apparently they're brilliant for the GTR. They are making good inroads in the US and Australia on working with these boxes
35iS, Black/Coral Red, 19" BBS CH-R/MPSS, Eiback Pro Springs, CoolCarbon Performance Pads, Golf T, Stubby, LED 80w halo's, X6 tips, CarPro CQuartz, Custom painted accessories

Image

User avatar
R.E92
Senior Member
Senior Member
Posts: 1644
Joined: Wed Dec 04, 2013 10:10 am

How long are DCT boxes designed to last?

Post by R.E92 » Tue Dec 05, 2017 3:27 pm

stuartinzg wrote: Tue Dec 05, 2017 1:46 pm I've been speaking to ken at wedge performance who said he has access to the pressure line tables for the DCT now, through MHD.
They are running 600 whp on stock units and the clutches appear to be holding. He also recommends SSP over Dodson, a lot of issues with Dodson clutches on the BMW DCT, although apparently they're brilliant for the GTR. They are making good inroads in the US and Australia on working with these boxes
What exactly did Ken say about the line pressure tables?

As far as I know, the pressure tables are inside the transmission control unit(TCU). MHD only flashes the engine control unit(ECU). The ECU sends a calculated torque output value to the TCU which then uses that torque value to decide what line pressure to use.

Editing the line pressure tables would be awesome if they are actually accessible.

User avatar
stuartinzg
Member
Member
Posts: 838
Joined: Fri Aug 14, 2015 7:33 am

How long are DCT boxes designed to last?

Post by stuartinzg » Tue Dec 05, 2017 3:56 pm

He recons they can now - didn't go into details. I'll look back through the whatsapp log when I get home
35iS, Black/Coral Red, 19" BBS CH-R/MPSS, Eiback Pro Springs, CoolCarbon Performance Pads, Golf T, Stubby, LED 80w halo's, X6 tips, CarPro CQuartz, Custom painted accessories

Image

Post Reply