diff wiggle?

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bosers
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Post Tue May 05, 2015 7:48 pm

Hi, as I was under the car today I noticed that the propshaft where it goes through the rear subframe isn't central to the hole, but nearer to the edge on the drivers side. I wondered if there is any adjustment on the diff holding mounts to allow a slight twist of diff to make prop more central in the hole? Didn't get a pic unfortunately. Thanks Joe.
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motormanmick
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Post Wed May 06, 2015 8:03 am

Hello Joe,
the holes are a fraction bigger than the bolts that hold the diff in situ, so there is a little bit of play, but not much, don't know how long you have owned the car? but sometimes the bolts can work a little loose if not tightened up properly (previous owner) and may have enlarged, then been tightened correctly, but not in correct position, it that makes sense? so back them off a bit and see how much play there is and see if there is enough to get the diff where it should be.
One of the other zoners may know if your current position is correct or not, cheers.
HairyScreech
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Post Wed May 06, 2015 1:09 pm

I'm pretty sure that's normal, the pinion is offset to one side on the diff.

E36 compacts are like it as are e21s.

My E30 with Z3 diff is certainly like it.
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jmc330i
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Post Wed May 06, 2015 1:17 pm

Yup my touring is the same. You certainly wouldn't be able to move the diff to get the prop central through the beam.
James
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'93 318i touring 16v
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bosers
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Post Wed May 06, 2015 1:33 pm

Ok that's a relief, thanks for the replies. I put the diff on and didn't notice at the time how it lined up with the beam.
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Brianmoooore
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Post Wed May 06, 2015 2:38 pm

It is important for the life of the prop. that it does NOT line up with the centre bearing, and the centre bearing must NOT line up with the gearbox. A prop shaft that runs dead straight will soon damage the UJ bearings.
HairyScreech
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Post Wed May 06, 2015 4:56 pm

^ and the above.

I think not taking account of the above is one of the biggest reasons some of the engine swaps go through guibos, props, centre bearings and diffs so quickly.

The recommendation someone made of tuning the centre bearing around when fitting an e36 prop might not be as stupid as it sounds, The E30 centre bearing is also offset to one side.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

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bosers
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Post Wed May 06, 2015 8:00 pm

Great, thanks all. It makes sense when you think about it. Hadn't thought about it before though. :D