front flex disk question

[Dirty325ix]

Is there a thickness difference between front flex disk and the rear one because my front guibo bolts hit the transmission cover and I tried to reuse a old rear flex disk
I tried to look it up on real OEM and got confused as which is which

http://www.realoem.com/bmw/showparts.do?model=1293&mospid=47311&btnr=26_0040&hg=26&fg=10

[frankie591]

.

[Northern]

There's one at the rear output of the tcase, and one between the tcase and trans as well. Not just for the front ds.

I had heard that the front guibo is thinner than the rear, with the same bolt pattern/diameter. I read a thread somewhere about the use of a rear guibo in place of the front to act as a driveshaft spacer, but I've yet to try it myself

[frankie591]

didn't know you were talking about an ix...backs out of thread :razz:

[williamtii]

Yes. The front shaft Guibo is the skinny one, the rear is in the middle, and the one between the trans and T-case is extra fat (96mm?) and larger bolt pattern. You can use the rear guibo for the front but you have to eliminate the centering pin which I personally was not comfortable with.

[Dirty325ix]

^^^^I kinda wanna do that because I just tried that and it fit

Anyone have any experience with this

Long term

[nomansland92]

I thought i also heard you can use a flex disk from an x5 or something to act as a spacer instead to lightning the splines?

[nando]

you use the x5 centering pin. the front x5 flex disk is the same thing as the rear ix part. the X5 centering pin is longer so it still mates with the front diff. it fits the E30 driveshaft perfectly.

[flyboyx]

this is true, but the bolts from the thicker rear guibo will hit the bell housing flange on the oil pan. in order to make this work, you have to grind away about 1/8" of material off that flange. the pan doesn't hold oil there you do don't have to worry about having a disaster on your hands.

[Northern]

if you just use washers/a spacer on the driveshaft, do you still need the x5 centering pin? Also, anyone have the P/N of this centering pin?

[moto650]

Perhaps part #4. Some of the IX experts here can chime in to confirm/deny

From RealOEM

[nando]

yes

I still think washers are pretty pointless, another 1/4" isn't going to do you a whole lot of good. but the flex disk is easy enough, although it's also a bit more expensive.

I want to say my X5 centering pin cost about $40

[Northern]

I wouldn't look at it as another 1/4", but as a percentage added to the original "penetration" depth. I think an extra 1/4" would be a good improvement over stock.

If the stock depth is 3/4", then another 1/4" is a 33% increase, which doesn't sound bad at all to me.

If the E53 front centering pin is only needed if you run a larger guibo, then I feel like its faster/easier to make a spacer using a spare DS as a template. If I didn't have the material to do so, I would definitely go the E53 pin route.


EDIT: Also, I came across a different P/N for the "centering flange" that you(Chris) posted in a previous thread and RealOEM here. Note the two P/Ns for MY2000. Any chance you could find your blunt invoice from like 2009 to find out for sure? hahaha

[nando]

I don't think you can actually get 1/4" without interference between the flange bolts and the transmission cover though.

I have part # 26201227191. I haven't looked at the other part # to see the difference.

anyway, spline engagement is only a small part of it. I still believe the most critical aspect of the front driveshaft is lubrication.

[Northern]

Thanks for the confirmation on the P/N.

I wouldn't be surprised if improper lubrication(or lack thereof) is to blame for 90% of Front DS failures. But with more power being added, I can't see proper lubrication being the sole solution.