E34 - E30 diff

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Jnielsen
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Post Sun Jun 07, 2015 12:35 pm

This topic I sure has been covered, but don't seem to be able to find anything...

I am at the final stage of my E30 hill climb/track car build. Unfortunately the car has a welded diff, which is crap. So in my search I have found myself an E34 diff. Now my question is, is the LSD internals a straight swap from the E34 diff to my E30 diff. No need to shim anything?? I like the ratio which is on the car now so unbolt the crown wheel and bolt it onto the lsd carrier and install everything again, or am I totally off on this one???

The car is an E30 325I with a medium case diff(188) and the E34 diff is an 3.46, 188 with 25% lock.

I have never had a diff opened before so it's gonna be new to me;)
DanThe
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Post Sun Jun 07, 2015 1:16 pm

Contact Gareth on here, diff building expert and he is a straight down the line no nonsense trustworthy chap 8)
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Jnielsen
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Post Sun Jun 07, 2015 1:21 pm

I'll try and contact him, thanks!
heathy325
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Post Sun Jun 07, 2015 2:47 pm

I've just done this the other way round so I'm pretty sure it's a yes I've taken the crown wheel and pinion from an e34 and put the e30 LSD unit on the crown wheel and rebuilt if your using the same gears and just changing the LSD unit it shuldent need a re shim
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Jnielsen
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Post Sun Jun 07, 2015 7:58 pm

Sounds good. It should be the same then, just the other way around. I have the option of the E34 diff and a small case e30 320 lsd with the right gearing, just need to get answers from the sellers regarding price. But from what I can read, the small/medium case diff's is bolt on's, only a small adjustment of the prop shaft?7

They are not easy to find these diff's. In Denmark we are talking £550-600 for a diff!!