Hey guys,
I took my wheels off and was wondering what size my rear wheels are. The front were straight forward, 7.5 width (993.362.134.05).

The rears not so much as both part numbers are stamped on the back of my rear wheels:
9in width part # (993.362.138.00 "B")
10in width part # (993.362.140.00 "A")

Both offsets are stamped too:
9in offset and width- (9Jx18-ET52 "B")
10in offset and width- (10Jx18-ET65 "A").

Can anyone point me in the right direction?

 

My 99 996 C2 was originally sold with a PLUS 1 wheel combo:

OEM WHEEL COMBO:
205/50/17x7 F 25.07 diameter; 50ET
255/40/17x9 R 25.03 diameter; 55ET

PLUS 1:
225/40/18x7.5 F 25.08 diameter; 50ET
265/35/18x10 R 25.30 diameter; 65ET

Are your rear tires: 265/35/18 ? If so, 65ET should be correct.

 

Yes, 265/35's in the rear! So, after 2 hours of searching I was about to post since I found an answer a little different to yours too and both make sense. If you look a little closer by the hub, you'll notice two boxes marked "A" and and "B". The box will be marked with an "X" with what wheel width/offset you have, my box was checked off on the letter "A" so the wheels definitely are the ET 65's you speak of:

The manufacturing process (whatever that was, as I wasn't there at the time) would be the same either way - but from the 996/986 era, for obvious manufacturing reasons, the central section was made for two width rims, so both these part numbers were 'cast' into the central section.

How do I know?

1) I read it somewhere

2) why else would you have two part numbers, with an A and B and ticked boxes on any object, unless some part of it was shared.

3) An alloy wheel came to me in a vision, and sayeth it was so.

 

Being that I was not the original owner of my 99 P-car, I have never seen the original PLUS 1 rear wheel. However, in the course of my research, an alloy wheel came to me in a vision, and sayeth it was so as well.

 

Why does it say 17 for the fronts if they are 18" tires?

 

What are you referencing?

The 996 will accept both 17" and 18" wheels/tires as long as they are within OEM specs.

 

Thanks