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3.07 LSD?

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Boggie
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3.07 LSD?

Post by Boggie » Wed Jul 18, 2018 9:52 pm

Hi All,

Was there ever a 3.07LSD fitted to the E24?
As I understand it only the M6/M635 got LSD and the ratio was 3.73 in Europe, 3.91(?) in the US.

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Ian
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GRNSHRK
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Re: 3.07 LSD?

Post by GRNSHRK » Wed Jul 18, 2018 9:55 pm

Ian, the European series I E12 based 635's with the M90 and CR trans did indeed have a 3.07 diff \:D/

However, this is a sideloader and is not compatible with the series II E28 chassis 6ers [-X

edit: you mention LSD, not sure about that but I would surmise that limited slip was an option [-o<

Perhaps at this point we need somebody who actually has one, to step up to the plate O:)
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Boggie
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Re: 3.07 LSD?

Post by Boggie » Wed Jul 18, 2018 10:05 pm

Thanks for the info. The reason I ask is that I have been speaking to a guy here that claims to have an E24 3.07-LSD. From his pictures the diff case looks similar to my '84 EU M635...
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Re: 3.07 LSD?

Post by GRNSHRK » Wed Jul 18, 2018 10:24 pm

Hmm, well, that does sound weird :-k

Pretty sure you have the correct ratios, however =D>

US M6 = 3.91
Euro M635 = 3.73

My advise would be to get her up so that you can turn the prop shaft and count the wheel revolutions \:D/
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Re: 3.07 LSD?

Post by Pasocb » Thu Jul 19, 2018 12:40 am

Yes, the early side loader 3.07 did come limited slip. I have a 1980 635 euro with one in the shop now.
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Re: 3.07 LSD?

Post by bpoliakoff » Thu Jul 19, 2018 3:12 am

Have an 81 euro came with an open 3:07 sideloader now has an LSD 3:07
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

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Ralph in Socal
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Re: 3.07 LSD?

Post by Ralph in Socal » Thu Jul 19, 2018 7:47 am

06/83 Euro 635 (8181587) e28 base with 3.07 Medium Case (188 MM) LSD with an autobox in front of it.

The M5/M6 cars were equipped with the Large Case (210 MM) LSD. They look very similar and unless you know the differences, a picture will not provide the "size" reference you need to determine which is which.

The Medium Case will have 6 bolts securing the Bearing Carrier Side Flanges to the case. The Large Case will have 8 bolts securing the flanges

All the mounting holes to secure the unit to the subframe are the same.

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Re: 3.07 LSD?

Post by wattsmonkey » Thu Jul 19, 2018 10:50 am

As far as I know, all UK manual 635 E24s (Series 2, E28-based) had the large case 3.07 LSD. That has certainly been the case with the three manual cars I've had direct experience of. Same as fitted to all E28 M535is. The earliest (y reg) cars had the medium case lsd in the same ratio.

Highlines had 3.64, with the motorsport editions having the LSD and presumably an option for others. Assume standard for manual.
Last edited by wattsmonkey on Thu Jul 19, 2018 11:08 am, edited 1 time in total.
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wattsmonkey
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Re: 3.07 LSD?

Post by wattsmonkey » Thu Jul 19, 2018 11:07 am

...and yes, M635s had 3.73:1 LSD as standard.
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Masked Man
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Re: 3.07 LSD?

Post by Masked Man » Thu Jul 19, 2018 2:24 pm

And Grace, my 1985 635CSiA came from the factory with a 3.25 open diff. (not a good match for the 182 horse green engine)

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Boggie
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Re: 3.07 LSD?

Post by Boggie » Thu Jul 19, 2018 8:06 pm

Ralph in Socal wrote:
Thu Jul 19, 2018 7:47 am
06/83 Euro 635 (8181587) e28 base with 3.07 Medium Case (188 MM) LSD with an autobox in front of it.

The M5/M6 cars were equipped with the Large Case (210 MM) LSD. They look very similar and unless you know the differences, a picture will not provide the "size" reference you need to determine which is which.

The Medium Case will have 6 bolts securing the Bearing Carrier Side Flanges to the case. The Large Case will have 8 bolts securing the flanges

All the mounting holes to secure the unit to the subframe are the same.

Ralph
Hi Ralph,
That is a great bit of info my '84 E24 EU M635, I just checked, has 8 bearing carrier bolts. The one this guy has been saying will fit my car, has 6 by the look of this picture: Image
So, this is an early (E12?) non-M 635CSI LSD?
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Re: 3.07 LSD?

Post by bpoliakoff » Fri Jul 20, 2018 1:18 am

No It is not a side loader diff. IIRC, the side loader was in use up through 5/82. I believe that to be a medium case diff, but am not dead sharp on the post 82 cars.
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

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Ralph in Socal
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Re: 3.07 LSD?

Post by Ralph in Socal » Wed Jul 25, 2018 9:41 pm

Sorry but that picture angle does not give a definitive answer. Ask the seller to pry off the stub axle to get a better shot. Good luck

Ralph
There is a very fine line between "Hobby" and Mental Illness.

85 635csi Zinno Auto
84 528i Euro
83 635 Euro Arktik
81 528i Kastanien 5-speed
88 528e Bronzit (Granpa Car)
86 535i Auto (For Sale)
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