Help! Need a recommendation for a rear diff
Thread Starter
Burning Brakes
Joined: Nov 2004
Posts: 961
Likes: 0
From: Albuquerque NM
Help! Need a recommendation for a rear diff
I just purchased the parts necessary to swap my A4 to an M6. I've got a 3.15 rear diff and need something to better match the manual. Car is about 50%/50% around town and highway. Thought I wanted a 3.42, but my mechanic is pushing a 3.73 - thoughts?
Intermediate
Joined: Feb 2005
Posts: 30
Likes: 0
Please pm me if you want to sell your 3.15 or call 601-660-0328 or emailme at delaughter74@hotmail.com .I am getting in line early because 2.73 sux. I dont have computer at home but will check mail at work wed or thur.thanks
Melting Slicks
Joined: Jul 2004
Posts: 2,826
Likes: 39
From: Central NJ
St. Jude Donor '05-'06-'08-'10
I recently swapped my 3.42's for 4.10's. I'd say you want at least the 3.73 with the 6sp. I think 3.90's or 4.10's are your best bet. I still cruise at 1800 rpm's at 70-72 mph. 
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Race Director
Joined: May 2003
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From: Paducah KY
Cruise-In VII Veteran
I've got a DTE 3.90 on order now. Had a 4.10 that was absolutely awesome for low end torque, but thought I needed the extra little bit of range the 3.90's provide to keep from shifting out of 4th at the track. 
Safety Car
Joined: Mar 2002
Posts: 3,780
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From: Southwest MI
Originally Posted by gdphillipsvette
I just purchased the parts necessary to swap my A4 to an M6. I've got a 3.15 rear diff and need something to better match the manual. Car is about 50%/50% around town and highway. Thought I wanted a 3.42, but my mechanic is pushing a 3.73 - thoughts?
what's the difference in 1/4 times? (3.42 to 4.10?), maybe a tenth? if you can get it to hook in first.....