1999 E39 528i Wagon - Flex Disc (Giubo) replacement

[jcain]

Attempting to replace the FD on my E39 wagon. I've done this a number of times on the E36.

The problem is that after unbolting the CV and making sure it was loose and unbolting the center support bearing and unbolting all of the flex disc bolts the driveshaft will not deflect enough to remove the flex disk.

I completely removed the exhaust so that is not an issue. I did not drop the rear transmission mount as the one on my car does not have the rubber bumper that causes issues on earlier model e39.

I attempted to use a 3 foot pry bar on the transmission/driveshaft flanges, but was not able to get enough deflection for removal of the driveshaft.

There is no damage to the car so the distance between the transmission output flange and the differential input flange is unchanged from factory.

The question I have is should there be enough travel in the driveshaft so that this should not be an issue and also would dropping the rear of the transmission help?

[Dmitry at Pelican Parts]

Hello - take a look at the link below to a DIY tech article from our site on the procedure. If you have any additional questions, please feel free to post a Comment just below the article and one of our techs will get back to you with more details. Hope this helps you and best of luck!

https://www.pelicanparts.com/BMW/techarticles/BMW-5-Series-E39/70-SUSPEN-Guibo_Flex_Disc_Replacement/70-SUSPEN-Guibo_Flex_Disc_Replacement.htm

[jcain]

I've looked at those articles. They are not helpful because they do not address the issue I am having, which is specifically the driveshaft will not deflect enough to be able to remove it.

I own 6 bmws. 4 E36s and 2 E39s. I have replaced the engines in both e36 and e39s. I have familiarity with how to replace the FD and with BMWs specifically.

However there does not seem to be enough front to rear movement coupled with angling the driveshaft to get it to clear the transmission output flange.

My thinking is perhaps the driveshaft is not moving enough front to rear because of an issue with the CV joint. I have searched on the internet, but there is no information on the length of travel the CV is capable of.

[jcain]

Okay, so here's the progress so far. It turns out that the CV joint is supposed to have about 3/8ths of an inch forward to aft movement if it is working properly. This one has no movement. I was able to slightly angle the CV joint so there is a gap between the CV joint and the differential input flange. I spent today using PB Blaster and a straw inserted through the gap to fill the CV joint with penetrating oil. I also rotated the driveshaft between each application of PB Blaster.

At the end of the day I was then able to get the driveshaft to move enough in the CV joint so that it could be deflected enough to remove it.

In retrospect I could probably just have cut the CV boot and applied the PB Blaster that way, but I had hoped that I would be able to reuse the CV as a new one is about $225.00.

Anyway, I will be installing a new CV joint as this one is obviously not working properly and I don't want to take the chance of it failing. Although it was not causing an issue until when removing it the angle of the driveshaft changed enough to cause it to bind and not release.

[CPC]

Haynes says driveshaft must be removed to replace guibo. Good luck!