[johnewhite]

More Info:
Manufacturer:
Advanced Composite Products and Technology
John Heard
800 799 7893
info@acpt.com
www.acpt.com
15602 Chemical Lane
Huntington Brach CA 94629-USA

DIY:
You will need to pick up a gasket for the connection at the diff. flange. See item 21 here - http://www.realoem.com/bmw/showparts.do?model=BL93&mospid=47714&btnr=26_0197& hg=26&fg=10. Your local dealership will probably have to order this item.

Also you will need to replace 3 nuts and bolts that attach the DS to the transmission guibo, item 2 in the illustration above. Because the 3-pronged flange of the new DS is thicker, you will need to get these longer than OEM bolts at your local hardware store. Make sure to use the same grade, e.g., 8.8 or 10.9 (should be marked on the top of the OEM bolts that you remove).

Finally, you will also need to replace the 6 bolts that connect the DS to the differential flange. Again, this is because the new DS flange is thicker than the OEM DS flange. Also, use the same grade bolts of course and you will need to match the width and pitch of the OEM bolts as the bolts screw into the differential flange.

Now, keep in mind, this was my experience and I have an 05 M3. Your experience might be different. Double check, measure and compare the connection points and bolts at both ends of the new DS with your OEM DS and this will tell you whether you need to replace the 3 nuts and bolts on the one end and the 6 bolts on the other end of the DS.

In terms of the swap, here's the procedure.

1. Raise and secure the M3.

2. Remove the V brace at the rear axle.

3. Remove the plastic undercover panel on the right (passenger) side near the rear wheel.

4. Remove Sections 1 and 2 of your exhaust (two sections between header/cat pipes and the muffler).

5. Remove the plastic undercover panel on the left at the point close to where the DS and transmission meet.

6. Remove the aluminum heat shield below the DS.

7. Depending on your tools, you may or may not need to remove the trans. support brace to get to the nuts on the guibo. I did. If you need to, support the trans. with a jack or jack stand. Then remove the 4 bolts underneath the brace and loosen the two connecting the brace to the trans. and slide the brace out and set aside.

8. Remove the OEM DS. Bolts out at the guibo, differential flange and support bracket in the middle. You will need to come out from underneath the car repeatedly to disengage and engage the parking brake and transmission gears so that you can turn the DS to get to the bolts in the guibo and diff. flange and to give you the leverage to loosen the nuts at the guibo.

9. Once the OEM DS is out, check to determine whether you can reuse the diff. flange bolts. Go the the hardware store to get the bolts and nuts you need, pickup the gasket from the dealership.

10. If it isn't already installed, install the new centering sleeve (the little rubber coupler) in the tip of the new DS where it goes into the guibo.

11. To install the new DS, you will need to loosen/remove the three bolts holding the diff. in place. This is because the new DS does not fold/bend in the middle like the OEM DS so you need to push the diff. back an additional inch or so to get the new DS in place. The only way to push the diff. is to loosen/remove its three connecting bolts. My suggestion is to substantially loosen the two hex bolts at the top of the diff. cover (back of the diff. facing the muffler). Then remove entirely the big single bolt connected through the side at the front/bottom of the diff. To ensure you don't strip that large bolt or the diff. hole, make sure to push up on the diff. and release as you work that bolt out and then later back in.

12. With the diff. having some flex now, you can connect the DS at the guibo, don't put the nuts on yet or just barley put them on - so the bolts don't pull out when working on the other end. Then, place the OEM gasket into the diff. flange and align it (of course you removed the almost certainly torn existing gasket that you are replacing). Now by maneuvering the diff. and the play in DS flange you should be able to seat the DS flange into the diff. flange and get a bolt finger tightened in there. With the parking brake off and the car not in gear turn, the DS or diff flange or wheels so that you can install and finger tighten each of the six diff. flange bolts.

13. Tighten each of the six bolts in a criss-cross fashion and tighten the 3 nuts and bolts at the guibo.

13. Reinstall and tighten the 3 diff. bolts and then retighten the DS at both ends.

14. Replace the trans. support brace, heat shield, exhaust sections 1 and 2, plastic undercover panels, and V brace.

[UYM3]

^ Thanks for all the info... i'll past this on to the buyer..