ZPOST
BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   ZPOST > BMW Z4 Roadster and Coupe > General BMW Z4 Forum
  TireRack

SUPPORT ZPOST BY DOING YOUR TIRERACK SHOPPING FROM THIS BANNER, THANKS!
Post Reply
 
Thread Tools Search this Thread
      07-25-2009, 09:04 PM   #1
E82tt6
Colonel
 
E82tt6's Avatar
 
Drives: '08 Black Saphire Z4 MC
Join Date: Oct 2007
Location: New Jersey

Posts: 2,629
iTrader: (0)

Very fast 1-->2=Grind. CDV?

Only issue I've had with the way the car drives. If I shift slowly (but not slowly enough to drop past the revs where 2nd will pick up. I'd say just about 3/4 second) I won't have any issues, but if I try to shift fast, 2nd will grind even if my foot is absolutely flat to the floor. Not trying to powershift or anything, just regular fast shift. My "fast" shifts in my 135i were generally a bit under .25 seconds, based on BT logging, but the CDV was removed in that car.

Will removing the CDV do the trick, or is this something I have to take the car to the dealer for?

Otherwise, I'm very impressed with the car. It continues to exceed my expectations, and it's capabilities in all regards are astounding. Sounds system is actually much better than expected, heh.
__________________
'08 Black Saphire/Black Z4 M Coupe
RIP Gretta: Blue Water/Lemon 135i. Died to save me.
-ChuckV
E82tt6 is offline  
0
Reply With Quote
      07-25-2009, 10:06 PM   #2
Starscream
Lieutenant Colonel
 
Starscream's Avatar
 
Drives: ///M Roadster + E92 335i 6MT
Join Date: Dec 2007
Location: Park Ridge NJ + Windermere FL

Posts: 1,985
iTrader: (22)

Did you just buy the car?

Reason I ask is that most people complain about this on the Z4M's,
It takes a little getting used to but you should be able to stop doing it,

I can tell you the CDV was done on my car within the first few days of taking delivery and I do believe it helps a lot,

The CDV slows down the clutch release and it would make sense that it could cause the grind,
I wouldn't remove it, a company called Zechausen Racing sells a modified valve that on visual inspection under the car appears to be stock,

http://www.zeckhausen.com/BMW/Z4-M_Coupe_Roadster.htm

According to board members some dealers get "funny" when it comes to any modifications, at least if it looks stock it doesn't throw up a red flag,

My dealer is too stupid to even notice such a thing,
__________________

Imola Red Roadster
Starscream is offline   United Kingdom
0
Reply With Quote
      07-25-2009, 10:40 PM   #3
E82tt6
Colonel
 
E82tt6's Avatar
 
Drives: '08 Black Saphire Z4 MC
Join Date: Oct 2007
Location: New Jersey

Posts: 2,629
iTrader: (0)

Yep, picked the car up today. Thanks for the tip on the modified CDV. I have a good relationship with the dealer, but you can never be too careful.

Am I just out shifing the syncros? Do I need to adopt a softer touch?
__________________
'08 Black Saphire/Black Z4 M Coupe
RIP Gretta: Blue Water/Lemon 135i. Died to save me.
-ChuckV
E82tt6 is offline  
0
Reply With Quote
      07-25-2009, 11:00 PM   #4
Starscream
Lieutenant Colonel
 
Starscream's Avatar
 
Drives: ///M Roadster + E92 335i 6MT
Join Date: Dec 2007
Location: Park Ridge NJ + Windermere FL

Posts: 1,985
iTrader: (22)

from what I understand the transmission BMW used for the Z4M is the same as the one from the 3.0si,
The E46 M3 transmission at the time wouldn't fit apparently so BMW used the si's trans,

The si transmission wasn't designed for the loads or revolutions of the S54 engine and that's why according to websites a lot of people have the 1-2 grind,

I have done it myself a few times when I first got the car, but now it seems I never do it,

Weird thing is, I can't actually remember what I do different

I am sure though a modified CDV valve will make the car shift a lot smoother, its a very noticeable difference
__________________

Imola Red Roadster
Starscream is offline   United Kingdom
0
Reply With Quote
      07-25-2009, 11:46 PM   #5
reRESERVEDFX
(oO (||||) (||||) Oo)
 
reRESERVEDFX's Avatar
 
Drives: 06 BMW Z4 3.0i 03 BMW M5 DINAN
Join Date: Oct 2008
Location: Downers Grove, IL

Posts: 165
iTrader: (0)

Send a message via AIM to reRESERVEDFX Send a message via Yahoo to reRESERVEDFX Send a message via Skype™ to reRESERVEDFX
It's not the transmission cause I have the same problem in the 3.0. The problem is the CDV! Get rid of that damn thing and a lot of stuff will come down to normal. CDV, clutch stop and clutch bushings are the first things u should put on a BMW! They're cheap too, CDV 35, stop 20, and bushings are 20 as well!
__________________
2006 Porsche 911 C4S Black/Black 6MT/Sport Chrono/Extended Leather/GT2 bucket seats/Turbo wheels
Soon to come 07 BMW Z4M Coupe Black/Red
reRESERVEDFX is offline   United_States
0
Reply With Quote
      07-26-2009, 12:11 PM   #6
thekurgan
Bad Lieutenant
 
thekurgan's Avatar
 
Drives: E90M3
Join Date: Aug 2007
Location: Sacramento

Posts: 2,586
iTrader: (0)

Garage List
2008 BMW M3  [0.00]
The CDV does help, but the transmission does require a gentle, respectful touch. The CDV does not affect the disengaging of the clutch, just the engaging, according to Dave Z. I've never had a grind and have changed the trans fluid twice in 10k as I felt it wasn't really broken in after 1200, so after I had it changed at 1200, I waited until the transmission felt broken in, smooth and going to 1st was smooth, then I changed the oil at that point.
__________________

08 E90M3 6MT Alpinweiss/Carbon/BMW Pedals/Dinan Exhaust/Rattle fixes
thekurgan is offline   United_States
0
Reply With Quote
      07-26-2009, 07:24 PM   #7
Z4MCJJ
Lieutenant
 
Z4MCJJ's Avatar
 
Drives: Z4MC
Join Date: Dec 2008
Location: Z4MC

Posts: 448
iTrader: (0)

My CDV is deleted...I still grind from time to time if I haven't driven my Z4MC in a while...and I drive it very little.
Z4MCJJ is offline  
0
Reply With Quote
      07-27-2009, 05:13 AM   #8
pvr
Private
 
Drives: Z4M
Join Date: Apr 2008
Location: UK

Posts: 55
iTrader: (0)

I have heard from a fellow owner of the M that they replaced the gearbox because of this issue. That was a 2006 M.
pvr is offline  
0
Reply With Quote
      07-27-2009, 09:41 AM   #9
onelove
Track Head
 
onelove's Avatar
 
Drives: 07 Z4M
Join Date: Jan 2008
Location: Orlando,FL

Posts: 501
iTrader: (0)

I get a grind from time to time in mine, usually 2-3 times a month when doing fast shifts.
onelove is offline   United_States
0
Reply With Quote
      07-27-2009, 11:30 AM   #10
Incompatible
Major
 
Drives: 07 AW Z4C 3.0Si
Join Date: Aug 2007
Location: San Diego

Posts: 1,131
iTrader: (1)

CDV delete does improve the clutch release and subsequently the feel, it does not have anything to do with the transmission grind on shifts. Grinding during shifts is primarily a function of the synchros being able to spin up and match rotation speed. Spin up can be affected by the viscosity and temperature of the trans lubricant, the rpm difference between the input shaft (engine rpm) and gear shaft, the speed of the shift, and the design/condition of the synchros.

There are a number of variables to deal with when trying to isolate the problem. Since most of us are stuck with what BMW put in the car, for good or bad, we have to work around any of the limitations. BMW may have gone with a more robust and durable design (to include reduced noise production) which compromised the synchros ability to rapidly spin up, I don't know. Like any other component, there is always a set of design considerations and compromises. Some manufacturer's have dealt with a similar problem by using a shift gate design which makes it near impossible to shift rapidly.

A large number of owners do not have the 1st to 2nd grind problem, but a few do. Some have resolved the issue with a change of shifting technique, some think that a different lubricant helped/resolved the problem. For some, nothing seems to work. And of course there is certainly a small percentage of transmissions which have an "out of spec" manufacturing problem.

As many have stated, the grind doesn't always occur and appears to happen only in the high rpm shift range. Maybe a specific and objective (no rants) "technical" thread which provides production date of car, type and frequency of grind problem, vehicle/transmission mileage, corrective action taken (such as lubricant change and type, warranty replacement.....), and the effectiveness of the corrective action would benefit all of us to find a common solution or at least minimize the problem.

I now relinquish my soapbox.
__________________
If you can't take the time to teach a kid something good, someone will take the time to teach them something bad.
Incompatible is offline   United_States
0
Reply With Quote
      07-27-2009, 05:49 PM   #11
thekurgan
Bad Lieutenant
 
thekurgan's Avatar
 
Drives: E90M3
Join Date: Aug 2007
Location: Sacramento

Posts: 2,586
iTrader: (0)

Garage List
2008 BMW M3  [0.00]
Quote:
Originally Posted by Incompatible View Post
CDV delete does improve the clutch release and subsequently the feel,
No, it's a one-way valve, only on engagement.

http://www.bimmerfest.com/forums/sho...75&postcount=4
__________________

08 E90M3 6MT Alpinweiss/Carbon/BMW Pedals/Dinan Exhaust/Rattle fixes
thekurgan is offline   United_States
0
Reply With Quote
      07-27-2009, 05:56 PM   #12
Incompatible
Major
 
Drives: 07 AW Z4C 3.0Si
Join Date: Aug 2007
Location: San Diego

Posts: 1,131
iTrader: (1)

Quote:
Originally Posted by thekurgan View Post
No, it's a one-way valve, only on engagement.

http://www.bimmerfest.com/forums/sho...75&postcount=4
Poor choice of words on my part, you are correct. (I was thinking in terms of releasing the pedal....which engages the clutch.)
__________________
If you can't take the time to teach a kid something good, someone will take the time to teach them something bad.
Incompatible is offline   United_States
0
Reply With Quote
      07-27-2009, 06:07 PM   #13
thekurgan
Bad Lieutenant
 
thekurgan's Avatar
 
Drives: E90M3
Join Date: Aug 2007
Location: Sacramento

Posts: 2,586
iTrader: (0)

Garage List
2008 BMW M3  [0.00]
Quote:
Originally Posted by Incompatible View Post
Poor choice of words on my part, you are correct. (I was thinking in terms of releasing the pedal....which engages the clutch.)
I actually thought the same thing, I couldn't tell the difference when I blew through the zeck cdv when I received it. I don't have the grind, but I know 2 others that do. Has anyone tried Redline D4 ATF as a replacement for the BMW fluid? I wasn't sure if the BMW fluid was a 100% synthetic, some say it works, some say it makes no difference.
__________________

08 E90M3 6MT Alpinweiss/Carbon/BMW Pedals/Dinan Exhaust/Rattle fixes
thekurgan is offline   United_States
0
Reply With Quote
      07-27-2009, 06:36 PM   #14
fatmatt0116
Hooligan
 
fatmatt0116's Avatar
 
Drives: 2011 X5 5.0
Join Date: Dec 2008
Location: Boston, MA

Posts: 547
iTrader: (0)

Sigh.

I have read this exact thread from 2007 on this board after researching the problem as it has occurred in my car at the same frequency before and after the cdv modification. The only definitive solution is a transmission replacement (doh!). I have tried all manner of shifting technique finesse etc to no avail. The truth is a sticker price 57k sports car should have absolutely no difficulty quickly shifting from 1st to 2nd at any rpm, period.

I'm no mechanic, but from what I gather the problem has something to do with the synchros. Mine was sitting on the floor for 2 years before I bought it in late '08 with probably a few hundred jaggofs having banged the shifter around, who knows what the effect was. As it is a difficult problem to reproduce, the dealer ofcourse looked at me like an idiot when I brought it to them despite the fact that I printed out the threads from 2007 in which several people wound up having their transmission replaced and in fact listed the part number for the new transmission (I got the old "Don't believe everything you read on the internet my friend."). Frustrating, but not difficult to understand their perspective as I could see myself saying the same thing in their shoes. Fortunately my service department staff have been great since day one and agreed to get in touch with BMW NA to find out about the problem. I am scheduled to have a new transmission installed next month. Halla-f*ckin-lullah.

What I did not mention and what is the most alarming thing about the transmission problem is that after I get the grind, if I then come to a complete stop and try to put the car into first, I find that I am locked out and am sitting there like a jackoff in my 60k sports car that I cannot get to move. In the meantime people are looking at me like I am some kind of ass hole who doesn't know how to drive his father's sports car. I have to shut the thing off, cycle through all the gears, and then turn it back on again which resets it. This is an element that I have yet to hear another z4 m owner complain of, and hope not to.

Anyhow, I decided I would sell the car if they didn't fix the problem, and this proclamation seemed to move things along when I spoke with the BMW NA representative, who was very nice by the way.


Good luck with your situation. I'm still happy I bought the car but holding my breath until after the tranny transplant.
__________________

2007 Imola Red Z4 M Coupe
2004 Navy Blue BMW 325Ci
fatmatt0116 is offline   United_States
0
Reply With Quote
      07-27-2009, 11:28 PM   #15
VitaminT
Second Lieutenant
 
Drives: 2006 M Roadster
Join Date: Sep 2007
Location: Alabama

Posts: 295
iTrader: (0)

Mine only does it on high RPM shifts. Mine sometimes feels like the selector gets past the syncro but doesn't engage on the teeth for second gear as it will go in about half way and make this real nasty high pitched BBBBzzzzzzzzzzzz noise. Not a grind, but not good none the less.

I haven't had it lock me out of a gear like you mentioned but have had to shift to second at a light to be able to get it into first. I guess it doesn't matter now that a new tranny is scheduled but if it locks you out, can you put it in neutral, let the pedal out, push the pedal back in and then select first?
VitaminT is offline   United_States
0
Reply With Quote
      07-27-2009, 11:35 PM   #16
fatmatt0116
Hooligan
 
fatmatt0116's Avatar
 
Drives: 2011 X5 5.0
Join Date: Dec 2008
Location: Boston, MA

Posts: 547
iTrader: (0)

Yes, grindwise we have the identical problem. no, try as i might, i cannot get it back into first after this happens, no matter how many times i release the clutch. by default, it is in neutral after grinding since it won't go into gear. typically the grind is at high rpms, though it happened once when i shifted between 3-4k. the lockout has happened about 3 times in the past 2-3 months.
__________________

2007 Imola Red Z4 M Coupe
2004 Navy Blue BMW 325Ci
fatmatt0116 is offline   United_States
0
Reply With Quote
      10-22-2009, 11:18 PM   #17
MVF4Rrider
PCA, BMWCCA
 
MVF4Rrider's Avatar
 
Drives: 997S, MV Agusta F4, E46 M3
Join Date: Apr 2008
Location: Las Vegas NV

Posts: 2,060
iTrader: (0)

Before I departed Germany in early June of this year, I inquired about the grind and was told it's all shifting technique. They told me to hold the gear shift with firm pressure to the left as you pull the lever into 2nd (keep the left pressure all the way through the shift). I haven't had a grind since and I can shift at high rpms at will. CDV has nothing to do with it.
__________________
'08 Carrera S 6MT Guards Red/Black ext leather, Carbon fiber pkg, sport exh, sport chrono +, PASM, Nav, Bose, 19" forged turbos, red tranny tunnel
'07 MV Agusta F4 1000 R 1+1, Corse Red/Silver, RG3 race pipes and factory race ECU
MVF4Rrider is offline  
0
Reply With Quote
      10-23-2009, 12:40 AM   #18
scotch1217
New Member
 
scotch1217's Avatar
 
Drives: 2003 Z4 3.0i
Join Date: Oct 2009
Location: Germany

Posts: 22
iTrader: (0)

For everyone not in an M...it's your technique...sorry, but that's what's up.

For everyone in an M. Your tranny got mated to the wrong engine at factory. Somewhere in the adaption the synchros got turned around...but it also has to do with power. For example in the si, there's a lot more power running through the tranny than in the 3.0i in 1st gear. In the si you can alter your technique to counter act this, but with the M...1st gear is pretty much useless...plain and simple, you can't put that kind of power into a car with out a tranny that can handle it...
scotch1217 is offline   Germany
0
Reply With Quote
      10-23-2009, 07:20 AM   #19
thekurgan
Bad Lieutenant
 
thekurgan's Avatar
 
Drives: E90M3
Join Date: Aug 2007
Location: Sacramento

Posts: 2,586
iTrader: (0)

Garage List
2008 BMW M3  [0.00]
The tranny for the M is just fine, these are not dragsters, they are more suited for a track where 1st would rarely be used. There haven't been any issues I've read where the tranny has failed in the M.
__________________

08 E90M3 6MT Alpinweiss/Carbon/BMW Pedals/Dinan Exhaust/Rattle fixes
thekurgan is offline   United_States
0
Reply With Quote
      10-23-2009, 07:39 AM   #20
scotch1217
New Member
 
scotch1217's Avatar
 
Drives: 2003 Z4 3.0i
Join Date: Oct 2009
Location: Germany

Posts: 22
iTrader: (0)

Nobody's saying the tranny is going to fail, but when you make the 1 and 2 synchros out of brass you're going to have some grinding issues...the S54 wasn't meant for that transmission...plain and simple...you M guys are way too sensitive about this by the way...you want to fix it, bleed the clutch every so often...
__________________

2003 BMW Z4 3.0i - Merlotrot Red, Tan Leather, Carver Stereo+Navigation, aux input, 17 inch premium alloys, Bridgestone Blizzaks, SKN CHIP Tune
scotch1217 is offline   Germany
0
Reply With Quote
      10-23-2009, 08:01 AM   #21
MVF4Rrider
PCA, BMWCCA
 
MVF4Rrider's Avatar
 
Drives: 997S, MV Agusta F4, E46 M3
Join Date: Apr 2008
Location: Las Vegas NV

Posts: 2,060
iTrader: (0)

^^ It will grind at power levels equal to your car. The trans can't differentiate which motor it's mated to. The trans may have a design/materials issue, but if you do as i stated you won't have any more grinds and that's about all we can do at this point. I'm still using the OEM gear oil. I may change to something better to see if it makes any difference.
__________________
'08 Carrera S 6MT Guards Red/Black ext leather, Carbon fiber pkg, sport exh, sport chrono +, PASM, Nav, Bose, 19" forged turbos, red tranny tunnel
'07 MV Agusta F4 1000 R 1+1, Corse Red/Silver, RG3 race pipes and factory race ECU
MVF4Rrider is offline  
0
Reply With Quote
      10-23-2009, 10:43 AM   #22
zeroselect
New Member
 
Drives: Z4 M Coupe
Join Date: Jul 2009
Location: Fairfax, VA

Posts: 25
iTrader: (0)

I have this problem as well. I never do drag launches with the car I usually do autox and track event with it. Taking it real easy it never has a problem only when its in high rpm and shifting quickly but not aggressivly. I never have issue like this in any of my other cars.

I'm going to try changing the way i shift and see if it disappears and if that doesn't work i'm going to replace the shifter with the UUC to see if that helps as well.

edit: I haven't done the CDV delete yet but it wouldn't even apply to this problem anyways.
zeroselect is offline  
0
Reply With Quote
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -5. The time now is 08:37 AM.




zpost
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST