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Free Diff Update - WTF???
TimC - 22/10/06 at 07:37 PM

Evenin'

Need some follow-up help after my recent tag cleaning post.

Had a choice of 4 diffs. Two were 7.5" so not what I wanted and the other was a 3.92 non LSD so also no good to me.

So, I opted for No.4 and now I'm really confused.

Firstly, I can't find any reference to it's tag code - it's as follows:
V85 BB AA 362
So, do we think it's an LSD or not?

Also there's something else not right. When you turn one of the driveshaft flanges the other turns the same way. I thought all these Diffs (according to the Sierra forum guide) would turn the drive flange the opposite way??

Finally, it is impossible to turn the drive flange while preventing the input flange from moving.

This is how I imagine a locked diff to operate.

Can someone put me back on track??

Ta

TC

[Edited on 22/10/06 by TimC]


flak monkey - 22/10/06 at 07:40 PM

Both output flanges will turn the same way on an LSD as far as i know.

I would guess its a 3.62 LSD you have...though I stand to be corrected.

Theres a list of diff ratio codes on my site in the FAQ.

If you really want to know, take the back off and the ratio is painted on the crown wheel, you will also soon see if its an LSD

David


Liam - 22/10/06 at 07:44 PM

sounds like a nice tight LSD. Try and turn the outputs in opposite directions. It should be difficult but you should be able to.

Liam


need4speed - 22/10/06 at 08:01 PM

I'm sure AA means LSD and all the other thing sound correct for a LSD.

Nice find.

Dave


TimC - 22/10/06 at 08:04 PM

quote:
Originally posted by Liam
sounds like a nice tight LSD. Try and turn the outputs in opposite directions. It should be difficult but you should be able to.

Liam


I can just get them to turn in opposite directions. So, do we think I've done ok!?


jacko - 22/10/06 at 08:06 PM

quote:
Originally posted by flak monkey
Both output flanges will turn the same way on an LSD as far as i know.

I would guess its a 3.62 LSD you have...though I stand to be corrected.

Theres a list of diff ratio codes on my site in the FAQ.

If you really want to know, take the back off and the ratio is painted on the crown wheel, you will also soon see if its an LSD

David
AS David says 3.62 lsd
Jacko


aerobrick - 22/10/06 at 09:20 PM

Sorry but log into this site
www.fordsierraclub.co.uk.

This guys and gals are very helpful and will give any info you may ask on sierra bits.

They also can supply and buy bits of you if needs be

As far as i can recall a lsd diff tag needs A minimum of 3 AAA in the code sequence.


Though i stand to be corrected


mackei23b - 23/10/06 at 07:51 AM

Hi there

I'm sure this was the code for my LSD, AA denoting an LSD, while the 362 give the ratio at 3.62.

Hope this helps

Ian

[Edited on 23/10/06 by mackei23b]


chockymonster - 23/10/06 at 08:11 AM

AA means LSD

Any other letters in the centre means open diff.


DaveFJ - 23/10/06 at 09:37 AM

I always thought a simple check was that all LSD diffs have output flanges for bolt on drive shafts. ?
(or are there some odd mixes out there?)


andrew.carwithen - 23/10/06 at 11:32 AM

quote:
Originally posted by DaveFJ
I always thought a simple check was that all LSD diffs have output flanges for bolt on drive shafts. ?
(or are there some odd mixes out there?)


They do, but there are also various Sierra models that use bolt-on shafts with open diffs - such as the XR4i, for example. So bolt-on flanges are not the definitive answer when identifying an LSD.


Gav - 23/10/06 at 08:40 PM

My 3.62 LSD also has AA (which iunderstood to be for a LSD) in the tag and is similar in operation to yours.


seventhheaven - 9/11/10 at 06:01 PM

I'm starting to build a database of Sierra/Granada/Escort/Scorpio rear differentials and codes:
http://www.super7thheaven.co.uk/Sierra_Rear_Differential

It lists all the codes I have found so far - for both 7" and 7.5".

I've also put the rebuild manuals on there.

It should help you find or identify your axle.

From a code you should be able to see if it's :
- a lobro or tripod,
- 7" or 7.5"
- Top mount or side mount
- LSD or open
- What model to look for

To confirm the previous question, any code with 2 'A's will be an LSD. e.g. 83BG 4006 AA and 91GG 4006 ABA. The 'both shaft rotate the same' test is a good confirmation if you can lay your hand on one - not so good for buying from an auction site.

If anyone has one they can't see or wants listing (especially if they know what model and year it came from) email me on mark@vantagecms.com


MikeR - 9/11/10 at 06:32 PM

You should note that their are two types of push in shaft. The difference (that i'm aware of - there may be more) is that the part that pushes into the diff is difference sizes. The smaller is around 25mm and the larger around 30mm.

In the next week i'll be trying to replace a 30mm push in part with a 25mm push in part (ie my diff is 25mm and the shaft i want to use currently has the larger part on it so i'm going to swap over the bits and see what happens).


procomp - 9/11/10 at 07:55 PM

Hi Tim

Surely it's only the ratio your after. The fact of whether it's a Ford lsd is irrelevant as your going to have to use a quaife ATB anyhow surely.

Cheers Matt