rumatt's E46

[John V]

3.72 is the thickness in mm of the carrier shim on that side of the diff that will receive the Lsd.

Tailshaft seal is easy

[clyde]

Originally Posted by rumatt

Why does the diff have 3.72 written on it?

Originally Posted by John V

These snap ring pliers are the only way to get these snap rings out. On an E46 the snap rings double as retainers for the outer bearing races and as the axial locators of the differential unit. They're marked for their thickness (in mm, between around 3.4mm and 4.0mm). Generally, when installing an LSD you can get away with retaining the stock snap rings which is why I write their sizes on the case, but there are still a bunch of measurements that need to be taken to make sure. BMW doesn't sell these, so I keep a collection of about 30 of them to be able to build differentials without resorting to other methods.

Originally Posted by John V

3.72 is the thickness in mm of the carrier shim on that side of the diff that will receive the Lsd.

Tailshaft seal is easy

Which Matt would have known if he bothered to read the build thread JV is trying to do for Matt's car.