Advice on differentials
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Racer
Joined: Dec 2010
Posts: 427
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From: Redding Ca
Advice on differentials
I would like to change my 2.73 diff to..... 3.15 or 3.42. I need to know if I will need a tune after doing an upgrade like this.
Thanks in advance
- 2002 automatic
- 2.73 currently
Thanks in advance
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If I had to pick between those two differentials, I'd go with the 3.42s. You'll definitely notice a difference from the 2.73s.
Tech Contributor
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From: Anthony TX
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Wrong O bongo!
YES you WILL need a TUNE. Your transmission will go spastic and your shift points will be all over the place!
The PCM transmission parameters have to be adjusted for proper A4 operation after a gear change behind an Automatic..While you are doing DIFFERENTIAL MODS,,, please consider this. Its a fantastic reliability upgrade and it isnt all that much money and ITS EASY!
- C5, ragtopws6 , Upgrading your C5 rear with C6 Z06 guts, : http://forums.corvetteforum.com/c5-g...-z06-guts.html
-
- C5, Its_Go_Time, Output Shaft Install - Left and Right: http://forums.corvetteforum.com/c5-t...post1573407966
Contact Gene Culley www.gmpartshouse.com for a great deal on all the parts.
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From: Haymarket VA
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From: Hillsboro OR
When I converted from 2:73 to 3:42 (I also added a stall converter 
) I used an HP Tuner handset to change the gear ratio in the PCM to 3:42.
FWIW, When I updated the gear change, the HP Tuner set "automagically" adjusted the shift up/down points to the more aggressive gearing. Of course, it wasn't as aggressive as I would have liked so I had them manually adjusted to my liking.
HTH
) I used an HP Tuner handset to change the gear ratio in the PCM to 3:42. FWIW, When I updated the gear change, the HP Tuner set "automagically" adjusted the shift up/down points to the more aggressive gearing. Of course, it wasn't as aggressive as I would have liked so I had them manually adjusted to my liking.
HTH
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From: Oceanside California
I did the 3.42 from 2.73 swap. Defiantly needed a tune. I could not even make use of the gears as the engine would immediately red line when gunning it and it would sit there and bounce off the rev limiter and not shift.
Good news is (at least where I went) a transmission tune is around 150 bucks and only takes 10-20 minutes to do.
Dont get those damn super-chip or hyper-tech tuners. I bought one because it has an option for gear swaps, but go figure, it didn't do a thing. Even with the super-chip 3.42 gear tune, the redlining was happening. Ridiculous the **** that is sold out there. Nothing but a "real" tune for "your" vehicle is worth it.
Good news is (at least where I went) a transmission tune is around 150 bucks and only takes 10-20 minutes to do.
Dont get those damn super-chip or hyper-tech tuners. I bought one because it has an option for gear swaps, but go figure, it didn't do a thing. Even with the super-chip 3.42 gear tune, the redlining was happening. Ridiculous the **** that is sold out there. Nothing but a "real" tune for "your" vehicle is worth it.
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