I am getting ready to upgrade my rear end in the next few weeks (stock GU5 open). I was debating on either 3.73's or 3.55's but today I was offered a low mile GU6/G80 (auburn) rear for $75. Will I be happy with that or do I really want the 3.73 and my torsen I have for it? I'm the kind of person that doesn't mind using the used parts if I will be happy with it, but if it will leave more to be desired I would rather just spend the money once.
Also if you were me and you were going to build my rear end would you get 3.73's or 3.55's? Its the car in my signature and it sees a good amount of freeway driving. Milage isn't a huge concern, I have learned if I really want to enjoy the car I cant worry about the gas that its drinking.
RPM's @ 70MPH; speed at 6000RPM's (redline on my motor)
3.23- 2900; 145
3.42- 3050; 137
3.55- 3200; 132
3.73- 3350; 125

 

I figure what would be too much and then go with the one just below it. I wouldn't do all this and settle for less unless money or mileage is an issue.

 

auto or manual?
mods?

 

I have 3.42s' in my 93Z, A4........ Its a daily driver and still gets 20~24 MPG highway....

If you have a manual, then go with 3.73s'... From what I have read, its driver friendly...

 

I went from 2.73 Open to a 3.42 Auburn years ago. I was happy with the results. Still had good cruising comfort and the bottom-midrange was desirable as well. Thats with a A4 tranny. Also, IDK anyone who makes a 3.55 gear for the 7.5/7.625 diff. Usually its 2.73, 3.08, 3.23, 3.42, 3.73, 4.10 and so on.

 

There's not much difference between 3.23 and 3.42 IMO - I'd go with 3.73 if just doing gears. I went with 3.42 over my original 2.73 because I got a deal on a complete rear also.

 

Sorry I dont know why my signature dosent show up. I have a th400