Diff identification?

[Nambo]

So 20 odd years ago, during its first respray, my Stag was given a replacement diff.
Now Ive always had it in my mind that the fella said he couldn't get a Stag diff so had put a TR6 diff on and that it therefore had higher gearing.

I have subsequently allways considered my Stag to be over geared, a real pain in slow moving traffic for instance and far too long legged.

I have a overdrive manual by the way.

So, during my current rebuild, I purchased a recently rebuild diff off an e-bay man thinking I would get a diff with lower gearing.
When I recently took my "TR6 diff off, and comparing the ratios, I find both diffs to be 3.7 ratio which is the correct lower ratio for manual cars.

Never mind, the new diff has less play so I will use it, Iam just a bit worried that this "Stag" diff, when I bought a new back plate gasket for it, I found that the top and bottom right hand bolt holes, do not line up with the gasket, so I had to trim the gasket and use copper washers to prevent any leak down the thread.

So Iam now wondering if this "new" Diff I have is Stag or something else, and if so, can I still use it.

The part number stamped into the alloy back plate is 309033, whereas my "TR6" one says, 30572

The new diff body has the number 18681 whereas in a different place my old "TR6" diff says V3170.

Any views on how interchangeable those Triumph diffs are if the ratio is the same, why the back plate holes are in different places, will it still fit my car?

And lastly, how do you folk feel about the Stag gearing?, do you find it too long legged?

[keeny]

Hello Nambo, have a look at my thread new on page 3 Diff ratio help please ,this may help you
Keeny

[Goldstar]

309033 is the correct Stag Axle Rear Cover but there's no Stag part with a number beginning 18, the dIff case - technically called the Hypoid Housing Assy (apparently) was 518212

Parts Catalogue - Magic! I'm becoming a parts number geek

[stagmuffin]

309033 is the correct Stag Axle Rear Cover but there's no Stag part with a number beginning 18, the dIff case - technically called the Hypoid Housing Assy (apparently) was 518212

Parts Catalogue - Magic! I'm becoming a parts number geek

if you carry on like this your gonna need an ANORAK !!


steve

[Goldstar]

I know I'm starting to worry myself how interested I am in the details like that. I'll get me anorak

[Nambo]

309033 is the correct Stag Axle Rear Cover but there's no Stag part with a number beginning 18, the dIff case - technically called the Hypoid Housing Assy (apparently) was 518212

Parts Catalogue - Magic! I'm becoming a parts number geek

Actually, re-reading my post, I mixed up the alloy back plate numbers, my old diff which I was told was TR6 has the correct Stag backplate number of 309033 and the new diff has 30572 and is the one that the gasket almost lined up with, but not quite, so I wonder what this is from then?

I would guess then that if the housing assembly should have a six digit number, and mine is 5 digit, then I probably cannot see the first number which would make it 518681, this being the old diff that has the correct Stag backplate on.

[Goldstar]

I looked at 518681last night but there's no part with that number-sorry

[Nambo]

I looked at 518681last night but there's no part with that number-sorry

Looking at this diff with reading glasses and better light, the lightly stamped thin big font identification number, that indeed starts with LD on my old diff. the one the fella told me was TR6, will its obviously Stag.

The new Diff that has the different stud arrangement, about 2 inches before the 18681 number, there is the single letter L, nothing else, so what sort of number is L 18681 that has the similar but not quite the same backplate, and is 3.7 to 1 ratio?

[flying farmer]

Probably a 2 litre saloon diff, these were 3.7 ratio with a different rear cover. The 2.5 litre were prefixed MG, I think the 2 litre may have been ML
Neil

[StagnJag]

This link has a list of hte Diff prefixes.

http://club.triumph.org.uk/prefix1.htm

Rgds

Dave

[73stagman]

My diff is from a 2500 saloon, 3.45:1 ratio and I only found out when I bought a new diff rear cover gasket..... it didnt fit! The nice man at Rimmers told me where to look and what numbers to look for and I discovered the error. So being tight and having already spent too much that month on the car i bought some gasket material off ebay and made my own for around 3 quid.
I also have a rover v8 and 5 speed gear box so the slightly higher diff ratio should be OK. I have heard that the ratio change has been done to standard Stags in the past with varying degrees of satisfaction as always!

I also drilled, tapped for and fitted a drain plug in the main casing whilst it was in bits!

[richardthestag]

3.45 diff really suited my tv8 and bw35. But when i fitted the man o/d it wasnt as well matched so i put the original stag diff back .

Wonder why triumph didnt bother with the 3.45 for all auto stags