Differential type

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woerie938
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Location: Nieuwleusen, Netherlands

Tue May 06, 2014 10:48 pm

I've got a e36 316i Compact for bangerstox racing.

Now I've took the Tag of the differential and it says,
338V2562

I know 338 stands for the ratio 3,38.
But what means the V? Can it maybe be an Viscous LSD?

My e30 has the same though. I've asked this question once before on a dutch forum, but knowone seemed to know it. Some people said If you can pull 2 stripes you have an LSD but my experience is that it is possible with an open diff too.
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harry_p
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Wed May 07, 2014 12:35 am

All bmw limited slip diffs that I know of have an S, and as far as I know bmw diffs are all clutch plate, or Torsen.

A compact could possibly have a Torsen diff from a z3.

A quick way to tell if it's a clutch LSD is to jack either jack on rear wheel off the ground, handbrake off, gearbox in neutral. If you can turn the wheel easily it's not a clutch LSD. Or, raise both rear wheels, leave it in gear, try an spin one wheel. If it's an open diff the other wheel should spin the opposite way with very little resistance.

If it's a gear type Torsen diff, it's harder to tell by turning wheels, you'd be better off taking the rear cover off the diff.
cheers,

harry
gareth
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Wed May 07, 2014 1:03 am

Another trick to be sure, without needing a backplate gasket is to drop one drive shaft out. Then pop the output flange off and peer in the hole.

An open diff will have one cross pin in the centre, crossing the hole.
A plated LSD will have two pins in a cross.
A torsen LSD will have no cross pins.

Being a 3.38, it's almost certainly the original small case 3.38:1 open diff. Any BMW LSD tag i've ever seen will say 'S' in the code and if the rust hasn't removed it, will also say 'S' on the casing in white paint, about 1.5" high.
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woerie938
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Wed May 07, 2014 5:26 pm

Ok so It's probably an open diff. Doesn't really matter I was planning to weld it
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