Is this an LSD??

[Theo]

Terrible pictures I know but.....





Any help would be greatly appreciated.

[jonbuoy]

There is a metal tag hanging out from a bolt on the back, that's the best way you can tell.......it'll say something like 3:91 S if it's an LSD or a different ratio.

[Martinaston]

Judging by the length of the output flange i'd say no.

[Steviec]

Is this the tag in question?

If so, what do I use to clean it so I can actually see what it says?

[DaveD]

how about a vin search ...might that tell you

[gcorky]

vin search ok if original ,they do get swapped however!

[kam-325i]

Is this the tag in question?

If so, what do I use to clean it so I can actually see what it says?

I used a wire brush, the numbers & letters are stamped into the tag, if it is a LSD, it will read like "S3.63", its the S that denotes a LSD.

[x-works]

Put the car in gear, make sure the rear brakes are off, jack up one rear wheel while leaving
the other on the ground and try and turn it. If it turns its not an LSD, if it's very hard to turn
or won't turn it's an LSD.
If it's in a scrap yard and you can remove the rear cover, undo the 6 or 8 bolts holding the rear cover on,
when you look in there will be a large toothed gear to one side in both type's, the difference between
the two will be in an open/non LSD diff you will be able to see a lot more gears inside this cover
(2, 3 or 4 depending on what position it's in) in a LSD you will only be able to see the large toothed gear
and what looks like a dark grey/black cylinder attached at 90 degrees to the large gear.
This cylinder is what houses the LSD mechanism.

[Theo]

Cheers for the advice guys, think im going to have to attack it with a wire brush, and failing that jack it up, wouldnt be a problem if my trolley jacks were at home 100 miles away

[bigpimpin]

Just drop the clutch in first with plenty of revs (on a private road ) 1 black line = No LSD, 2 black lines = LSD.

Simple.

[Dan318-is]

Just drop the clutch in first with plenty of revs (on a private road ) 1 black line = No LSD, 2 black lines = LSD.

Simple.

Not always

[Theo]

Btw should have mentioned that this is a diff on a 318is, which i imagine looks slightly different to the bigger cased diffs on 325's.

[Dan318-is]

If its of a 318-is it will be a small case open diff 4.10 lsd, 90%

if thats an LSD mate your about to make a mint cos they are rare as fook!

[318is_irl]

its only a 6 bolt back plates so its not an lsd

[Theo]

Thats the hope mate, although it would be uncharacteristically lucky if it was.

[Dan318-is]

its only a 6 bolt back plates so its not an lsd

No, this just means it is small case and not large case; small case diffs were found on 318is; whether it is LSD or not will be anounced by the owner soon i hope!

[dazleeds]

cnt you just jack both rears up and spin em and see if they go same way??

is that right??

if they go opposits its open??

[Dan318-is]

cnt you just jack both rears up and spin em and see if they go same way??

is that right??

if they go opposits its open??

Correct. You can even jack it from the diff if you are careful this is how i did it; both wheels of the floor easily and quickly and without any scrubbing.

[dazleeds]

just looked at the tag on mine

the end of tag is pretty bad so cant tell if theres an s on it but rest says 391 920

whats that mean then??
thios is on the is by the way

[gcorky]

just got a 3.91 lsd off jonb and there is quite a good lock on outputs i.e both outputs travel the same way when spun.so jack a wheel up and it shouldnt spin.if it does its open.

[tonyppe]

lol about diffs.
i know mine doesnt have an lsd because if i give some power round a slow bend it spins one wheel only. also is some wet conditions only 1 wheel spins.

but!...

when i jack it up (both back wheels off) and spin 1 wheel, the other goes the same way! which ive been told indicates a diff that is on the way out. hehe