WTB Sierra differential

[James A]

I'm looking for a well used Sierra 7" differential, I plan to install new bearings and seals and a Quaife LSD, so as long as the case and gear set are good it can be in very rough shape.

This differential is going in a Caterham S3 standard width so I need the 7" NOT the 7.5".

Jim

[ChuckeD]

Would the differential from an 86 Merkur be the same?

[James A]

It is likely a 7 1/2 inch diff that would not fit. You can tell by looking at it, the upper through bolt mount on the 7" is cut away, the 7 1/2" is solid where the bolt goes through.

Everything is see out there from a Sierra looks to be 7 1/2" from what I have seen.

[scannon]

If you are putting the diff in a Caterham you can now use the BMW 1 series diffs. Caterham makes a cradle that will mount the BMW diff as a bolt in. You will need to modify the drive shaft and halfshafts to match. Apparently the Sierra differentials are no longer being produced and Caterham now supplies their kits with the BMW diffs and cradle.

 

However, it may be that the BMW diff will not work in place of the 7" Sierra diff. Jon at Caterham USA can probably tell you if it will work.

[jlumba81]

Found one on ebay.

[James A]

Yea, I saw this one, he says it is a 7" but it is a 7 1/2". Someone who buys this is not going to be very happy.

I guess I am going to have to breakdown and buy a rebuild from the UK.