z06 manual diff work with 1998 auto?
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
Likes: 10
From: Lewiston California
Thanks
thanks alot, Im ready to pay for a very low mi 3.42 diff, but it said it was manual, and I was nervous..Thanks alot, Ill let you know how it goes. Im in the hills, and the 2.73s just lug.. Im sure Ill like the 3.42s on these mountain roads...
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
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From: Lewiston California
Thanks, Im going to a driveline shop this moring and see if they can reprogram, or maybe buy a handheld tuner and do it in their parking lot after its installed, or could I drive it somewhere for a tune?
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Should be a nice improvement in performance.
Team Owner
Joined: Sep 2001
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From: Lake Elsinore, CA
You'll need to transfer the A4 diff adapter plate from the old to the new diff.
Here's the adapter plate I transferred from my 2.73 diff to my 3.42 diff a few years ago. It's held in essentially by the O-ring so it's not pressed in with a lot of force. You should replace the large, outer O-ring and shaft seal while it's out.
Here's the adapter plate I transferred from my 2.73 diff to my 3.42 diff a few years ago. It's held in essentially by the O-ring so it's not pressed in with a lot of force. You should replace the large, outer O-ring and shaft seal while it's out.
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Joined: Aug 2005
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From: CA.
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I did this exact same mod on my 98 auto trans car---You will need a "shift point correction" in your tune when changing gears--However you do not need a speedo correction when changing gear ratios
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
Likes: 10
From: Lewiston California
Dissapointed?
I did this exact same mod on my 98 auto trans car---You will need a "shift point correction" in your tune when changing gears--However you do not need a speedo correction when changing gear ratios
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Im confused, I was hoping changing the rear end to 3.42 would be a good mod for my car, especially in the hills that I live.
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Im confused, I was hoping changing the rear end to 3.42 would be a good mod for my car, especially in the hills that I live.
Le Mans Master
Joined: Mar 1999
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From: Palm Coast, FL
now have them upgraded to 3.73's and put in a 4K yank and feel the difference, you'll love the 3.42 but I think you should go with a higher stall, maybe 3,600. Don't fear the gear they say 
I ran the 3.73's and 4K yank until I wore it out then went with a 3,800 PA series. Car runs low tens NA
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
Likes: 10
From: Lewiston California
Shift Point Correction?
I did this exact same mod on my 98 auto trans car---You will need a "shift point correction" in your tune when changing gears--However you do not need a speedo correction when changing gear ratios
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Finally I was quite disappointed after this mod--Thining the lower gear ratio would help my 1/4 mile times and my 0-60 times----The gains were almost nothing --less than 1 tenth in the 1/4-----I was far more happy by adding a "stall converter" to my trans----This mod made my car almost 1/2 second quicker in the 1/4 mile and 2-3 tenths faster in the 0-60 times----- I ended up doing both mods but if I were to do it over again I would do the stall converter only----I would reccomend nothing smaller than a 3000 stall and trust me you will love it and your car will become a beast !!! ( my heads and cam 98 would run in the low 12's with the 3000 stall---)
Can I use a diablo Preditor to change the shift points? Or any other handheld tuner that you would recommend? There are no local tuners in my northern ca area..
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
Likes: 10
From: Lewiston California
You'll need to transfer the A4 diff adapter plate from the old to the new diff.
Here's the adapter plate I transferred from my 2.73 diff to my 3.42 diff a few years ago. It's held in essentially by the O-ring so it's not pressed in with a lot of force. You should replace the large, outer O-ring and shaft seal while it's out.
Here's the adapter plate I transferred from my 2.73 diff to my 3.42 diff a few years ago. It's held in essentially by the O-ring so it's not pressed in with a lot of force. You should replace the large, outer O-ring and shaft seal while it's out.
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
Thread Starter
Instructor
Joined: Sep 2014
Posts: 125
Likes: 10
From: Lewiston California