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is this an open dif?
ned - 31/7/06 at 12:22 PM

just want confirmation for a mate, he was told it was an lsd but it looks like an open dif to me.

cheers,

Ned.

Diff Inside 3
Diff Inside 3

Guinness - 31/7/06 at 12:25 PM

Yup, that's open, they normally have a cover on the back

Mike

P.S. Sorry, couldn't resist!

ned - 31/7/06 at 12:31 PM

ha harr

ned - 31/7/06 at 01:06 PM

fair enough, should have thought of that !

I still thought it was possible to tell by looking at it as I'm sure an lsd looks different in the centre of the dif where the planet gears are, just don't have a pic of an lsd to compare to and thought that someone here must have whipped the back off a ford lsd and be able to confirm either way..

Ned.

roadboy - 31/7/06 at 01:28 PM

Yup it's an open diff, no LSD
HTH
Ian

ned - 31/7/06 at 01:44 PM

Thanks Roadboy. The one pictured is a 7.5" scorpio dif, I guess the manufacturer that supplied it assumed that they were all lsd's in scorpio's...

Ned.

[Edited on 31/7/06 by ned]

Avoneer - 31/7/06 at 04:00 PM

That is definately an LSD.

The two plates on the back of the Crown Wheel have viscous fluid in-between them.

See here:

http://locostbuilders.co.uk/viewthread.php?tid=27608

Pat...

Liam - 31/7/06 at 04:09 PM

No no no

It is an LSD as you were told. How to tell?...

In an open diff the diff mechanism is dead central in the case as you look at it from the back. I.e. the middle pin of the spider gears is central between the two output bearings/flanges.

On an LSD the diff mech is shoved over to the right (as you look at the back of the diff) to make room for the viscous coupling which lives to the left of the spider gears under the crown wheel. Coincidentally (or not) the middle pin of the spider gears is now dead central to the input flange rather than the output flanges.

That looks rather like the diff mech is offset and central to the input flange (not totally 100% sure given the image distortion, but 99.9). Take out the circlips and remove the output flanges. On an open diff they are the same length, on an LSD they are different as the mech has been shoved over.

This can all be seen in the drawings of both diffs (7" versions in this case) in the sierra V6 haynes manual.

Not the first time i've seen an LSD dismissed as open by just having an uninformed look in the back!

Liam

meany - 31/7/06 at 04:12 PM

dont know if you have already seen this.

http://fordsierraclub.co.uk/forum/viewtopic.php?p=100105

Liam - 31/7/06 at 04:21 PM

quote:
Originally posted by Avoneer
That is definately an LSD.

The two plates on the back of the Crown Wheel have viscous fluid in-between them.

See here:

http://locostbuilders.co.uk/viewthread.php?tid=27608

Pat...


You're just looking at the crownwheel itself bolted to the diff cage there. You can't actually see the viscous coupling - it's burried deep inside. 10 or so plates in a completely sealed unit.

Liam

P.S. Only the bug-eye scorps have traction control instead of an LSD. An old style 24V scorp is a gauranted 7.5" LSD.

Confused but excited. - 31/7/06 at 05:55 PM

quote:
Originally posted by roadboy
Yup it's an open diff, no LSD
HTH
Ian
Jude Performance Services


Won't be using them then.