Welcome to Bimmerfest -- The #1 Online Community for BMW related information! Please enjoy the discussion forums below and share your experiences with the 200,000 current, new and past BMW owners. The forums are broken out by car model and into other special interest sections such as BMW European Delivery and a special forum to voice your questions to the many BMW dealers on the site to assist our members!

Please follow the links below to help get you started!

Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 7 Series / 8 Series > 7 Series - E38 (1995 - 2001)

7 Series - E38 (1995 - 2001)

Reply
 
Thread Tools Display Modes
  #1  
Old 07-11-2010, 12:01 PM
balance balance is offline
Officially Welcomed to the 'Fest
Location: NC
 
Join Date: Feb 2009
Posts: 766
Mein Auto: 97 740iL
Transmission issues...

I have a '97 740iL that was made in 12/96 which has a ZF 5HP30 transmission.

I have a problem with my transmission that seems to get progressively worse as time goes by. It started a few months ago when I got a noise in the motor that I couldn't figure out. I left the car at a friend's house for him to take a shot at finding out what the noise was. I told my friend that the noise would only happen with the engine under load, and then I left, only to return a few hours later to find out that he was power-braking for minutes at a time to try to locate the noise. The first issue with my tranny happened later that day.

While I'm pulling away from a stoplight, I get what feels like a shudder from the tranny right after it shifs from 1st to 2nd gear while the car is on Drive. When it shudders, it only lasts abuout 1 second. If I shift it into S4, or sport mode, the shudder happens right before the first upshift. It only does this while accelerating from a stop, and doesn't do it again until I accelerate from the next stoplight. This was the issue I was having for a few months, and while it annoyed me, I didn't really care too much until the issue I had a few nights ago.

I was driving on the highway, following a few cars on the left lane. They were going about 5 miles under the speed limit so when I decided to pass them, I went on the right and hit the kickdown switch, passed all of them, and then went back to the left lane. After that, the transmission would not hold gear while coasting. It would go in and out of gear unless I either hit the gas to accelerate, or let go of the gas completly. When I got to my exit, I shifted the car into sport mode to see if it would help, but it did not.

The next day I took the car to a transmission shop to get a free inspection. I did not drive the car sinse the night before, so it had alot of time to cool down. So when I drive the car to the shop, I realize that while the shudder was there, the car seemed to stay in gear just fine. The guys at the tranny shop didn't seem to know what the shudder was, and they told me that without feeling the other problem for themselves, they couldn't diagnose it. They told me to drive the car for a while, and if the problem comes back, to bring the car back. So I go driving for about an hour to try to get the problem to come back, but it never gets as bad as the night before. It happened every now and then for a few seconds at a time, only when the transmission was hot, but it always went away before I could bring it back to the shop.

I've been a mechanic for a few years, but I never really got into transmissions. From the little I do know about them, I'm starting to think that the torque converter is slipping, sinse the problem only seems to happen when the torque converter is supposed to be locked. I priced it out at $250 from a local warehouse that stocks transmission parts and I could do the job myself, but I would hate to go through all that labor just to find out that the problem was still there.

So my question is, does anyone have any ideas what the problem could be. Any advise or comments are welcome.
Reply With Quote
Advertisement
  #2  
Old 07-12-2010, 09:20 AM
DarkStarMedia DarkStarMedia is offline
Registered User
Location: Multiple States
 
Join Date: Jul 2010
Posts: 26
Mein Auto: 01 750iL
Get INPA and look at the tranny computer. It'll tell you if something is slipping. you might also want to do a fluid and filter change and maybe rebuild the valve body. It's all DIY.

Richard
Reply With Quote
  #3  
Old 07-12-2010, 01:09 PM
strifepeddler strifepeddler is offline
BimmerBro82
Location: Mesa, Arizona
 
Join Date: Jul 2010
Posts: 5
Mein Auto: 2003 BMW M5
Get a diagnostic tool hooked up to the car to read the fault codes. The fault codes will explain what might be failing. If you don't have access to that you can pull the plug on your fluid and see if it looks dirty and possibly any metal debris inside. I would be careful on a fluid and filter change, as the ZF fluid is not cheap, and its almost a shot in the dark, half the time if your transmission is acting up, the fluid isn't going to magically cure the problem, definitely sounds like a torque converter, but could also be valve body issues. No way to tell with transmission problems unless you have a diagnostic tool or have an experience technician open up the pan to see whats going on inside. Let us know what you figured out. Also you could try calling Auto Sports Unlimited in Michigan for advice, they are a ZF transmission rebuild shop that specialize in BMW transmissions. Ask for Stacy or Kirt, both have over 20 years with the zf5hp30 transmission and could probably get you a better deal on that torque converter as well.

http://www.autosportsunlimited.com - i think thats the website
Reply With Quote
  #4  
Old 07-12-2010, 04:25 PM
balance balance is offline
Officially Welcomed to the 'Fest
Location: NC
 
Join Date: Feb 2009
Posts: 766
Mein Auto: 97 740iL
Thanks for the info guys.

I scanned the transmission when the problem first happened, and then again today, but still no fault codes. I'm guessing the problem is mechanical and not electrical sinse it hasn't thrown a code yet. I have no problem with changing either the TC or the valve body, but I'd like some assurance about what the problem is before throwing money at it. I will definately call one of the guys at auto sports unlimited and see if they could give me any more info, and when I find out something new, I'll make another post.

Once again, thanks for the help guys.
Reply With Quote
  #5  
Old 07-12-2010, 04:28 PM
DarkStarMedia DarkStarMedia is offline
Registered User
Location: Multiple States
 
Join Date: Jul 2010
Posts: 26
Mein Auto: 01 750iL
Did you scan the main computer (OBDII) or the tranny computer.... if you used a standard scanner I can almost guarantee you that you did not see the tranny computer.
Reply With Quote
  #6  
Old 07-12-2010, 04:45 PM
balance balance is offline
Officially Welcomed to the 'Fest
Location: NC
 
Join Date: Feb 2009
Posts: 766
Mein Auto: 97 740iL
I have a snap-on mt 2500 with a BMW software cartridge and a circle adaptor for the connector in the hood.
Reply With Quote
  #7  
Old 07-12-2010, 05:41 PM
tommyb2b tommyb2b is offline
Registered User
Location: Hemet California
 
Join Date: Jul 2010
Posts: 57
Mein Auto: 1998 BMW 740IL
Yeah I would replace the TC and get a fluid and filter change.
__________________
Reply With Quote
  #8  
Old 07-13-2010, 01:13 PM
drchavana drchavana is offline
Registered User
Location: texas
 
Join Date: Jul 2010
Posts: 4
Mein Auto: 1998 bmw 740i
I have a 1998 740i. The trans failed safe program appeared on the dash after the car seemed to go into a high gear/ 4th or 5th. It now seems to work fine for about a mile every time i turn it on but then the above senerio happens again. I heard it could be the battery or alternator. Any other suggestions.
Reply With Quote
  #9  
Old 07-13-2010, 02:11 PM
DarkStarMedia DarkStarMedia is offline
Registered User
Location: Multiple States
 
Join Date: Jul 2010
Posts: 26
Mein Auto: 01 750iL
unlock your cluster and check your voltage

Richard
Reply With Quote
  #10  
Old 07-14-2010, 10:54 AM
tommyb2b tommyb2b is offline
Registered User
Location: Hemet California
 
Join Date: Jul 2010
Posts: 57
Mein Auto: 1998 BMW 740IL
Quote:
Originally Posted by drchavana View Post
I have a 1998 740i. The trans failed safe program appeared on the dash after the car seemed to go into a high gear/ 4th or 5th. It now seems to work fine for about a mile every time i turn it on but then the above senerio happens again. I heard it could be the battery or alternator. Any other suggestions.
Do you know how to unlcok your cluster? if not I can walk you threw it
__________________
Reply With Quote
  #11  
Old 07-14-2010, 11:50 AM
drchavana drchavana is offline
Registered User
Location: texas
 
Join Date: Jul 2010
Posts: 4
Mein Auto: 1998 bmw 740i
went home for lunch and unlocked the cluster and checked the voltage. The voltage checked out at 11-14 v. Ill take the car for a test drive after work today. ( youtube had the steps for unlocking the cluster.)
Reply With Quote
  #12  
Old 07-14-2010, 12:13 PM
DarkStarMedia DarkStarMedia is offline
Registered User
Location: Multiple States
 
Join Date: Jul 2010
Posts: 26
Mein Auto: 01 750iL
you have a bad alternator or battery... your voltage should never drop below about 13v while the engine is running.... and if you are below 12v with the engine off... your battery may need replacing.

Last edited by DarkStarMedia; 07-14-2010 at 12:23 PM.
Reply With Quote
  #13  
Old 07-14-2010, 09:18 PM
PETER NEWMAN's Avatar
PETER NEWMAN PETER NEWMAN is offline
Officially Welcomed to the 'Fest
Location: RAINHAM KENT UK
 
Join Date: Mar 2010
Posts: 271
Mein Auto: BMW 635 CSi BMW 730i E38
After reading about your tranny problems it sounds to me as though your gearbox clutches are slipping and if you had the gearbox sump removed you will most proberly find that the bottom of the sump is full of dark sludge and the filter will be blocked, I doubt that you will get away with just flushing the tranny oil and a tranny rebuild will be needed, Peter.
Reply With Quote
  #14  
Old 07-16-2010, 12:06 PM
balance balance is offline
Officially Welcomed to the 'Fest
Location: NC
 
Join Date: Feb 2009
Posts: 766
Mein Auto: 97 740iL
I called Auto Sports Unlimited today and talked to Dan. I was surprised at how willing to help, he seemed to be. He said that I should do a couple things first, before diagnosing the car, starting with disconnecting the battery for a few hours to reset the transmission computer and see if that helps. I doubt this will help but I will try it first and then call him tommorow.

He said that it sounds to him like a valve body but he is a service writer and wants to run it by his tech first and then let me know what he finds out when I call him later. He also assured me that they will have almost any part that I would need for a 5HP30 transmission.

I'll let you know what I find out tommorow.
Reply With Quote
  #15  
Old 07-16-2010, 11:35 PM
PETER NEWMAN's Avatar
PETER NEWMAN PETER NEWMAN is offline
Officially Welcomed to the 'Fest
Location: RAINHAM KENT UK
 
Join Date: Mar 2010
Posts: 271
Mein Auto: BMW 635 CSi BMW 730i E38
Smile Flat battery

I've come across lots of BMW's with batteries going flat or current drain and the way that I check them out is as follows but you will need an assistant, Disconnect a battery lead and check to see if you get a spark current jump from the battery to the battery lead and then you need to pull fuses out one at a time to determine which cuircuit has the power drain and if the spark jumping has gone, I must add that I have never come up against the same current loss whenever I've done this test and there are a lot of fuses on BMW's. Please keep me informed of your progress, Peter Newman.
Reply With Quote
  #16  
Old 07-19-2010, 02:32 PM
drchavana drchavana is offline
Registered User
Location: texas
 
Join Date: Jul 2010
Posts: 4
Mein Auto: 1998 bmw 740i
I had my transmission rebuilt and hasn't run right since. The mechanic essentialy said everything looks good and doesnt know what to do anymore. He gave up. I dont want to take to a BMW dealership because I know they will tell me I need a new transmission or try to sell me a new car. It continues in "fail safe program" mode and the battery and alternator are fine. Any short solutions I could try. I've already unlocked the cluster and checked the voltage and things are fine.

1998 740i with 84,000 miles

drchavana
Reply With Quote
  #17  
Old 07-19-2010, 02:34 PM
DarkStarMedia DarkStarMedia is offline
Registered User
Location: Multiple States
 
Join Date: Jul 2010
Posts: 26
Mein Auto: 01 750iL
you have to get into the EWS (Transmission computer) and read it directly. INPA can do this.

Richard
Reply With Quote
  #18  
Old 07-19-2010, 05:26 PM
PETER NEWMAN's Avatar
PETER NEWMAN PETER NEWMAN is offline
Officially Welcomed to the 'Fest
Location: RAINHAM KENT UK
 
Join Date: Mar 2010
Posts: 271
Mein Auto: BMW 635 CSi BMW 730i E38
My advise is to get a complete fault code test done for the engine and the transmission and maybe you should consider persuing your mechanic legaly through the courts to sort it out, Peter
Reply With Quote
  #19  
Old 07-24-2010, 04:46 PM
balance balance is offline
Officially Welcomed to the 'Fest
Location: NC
 
Join Date: Feb 2009
Posts: 766
Mein Auto: 97 740iL
Well, I called Auto Sports Unlimited again and told them that disconnecting the battery didn't help. The said that it would be very hard to diagnose transmission problems over the phone, but they still think that it is the valve body. They gave me a price on a used tranny, so I'm just going to keep driving until the old one goes out completely, then buy the a used one. If I'm driving sporty, the problem doesn't seem so bad, so I'll be driving on sport mode until the tranny goes.
Reply With Quote
Reply

Bookmarks


Forum Navigation
Go Back   Bimmerfest - BMW Forums > BMW Model Discussions > 7 Series / 8 Series > 7 Series - E38 (1995 - 2001)
Today's Posts Search
Thread Tools
Display Modes

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 -7. The time now is 03:53 PM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms