Why new rear diff why not just new gears??

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Jul 15, 2005 | 11:28 AM

CarsRFun

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Drifting

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From: Chesapeake Va

Why new rear diff why not just new gears??

As the title says,,, seems like everyone gets a whole new rear diff when they want to change the gear ratio.. why not just get new gears?? am I missing something??

Thanks

Jul 15, 2005 | 11:37 AM

debmwb

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From: Fort Worth Texas

Quote:

Originally Posted by CarsRFun

As the title says,,, seems like everyone gets a whole new rear diff when they want to change the gear ratio.. why not just get new gears?? am I missing something??

Thanks

The vette rear is a transaxle carrier and not just a pumpkin like on other cars. There are a number of issues with the carrier...1) Few shops can swap and setup the gears correctly...not that it can't be done...there is risk. 2) The 2.73 carrier will not take some of the other ratios. 3) The 2.73 carrier has less webbing than for instance the 3.42SP Z06 carrier.

So....typically the carrier is swapped as a unit...already setup and ready to rock-n-roll.

Jul 15, 2005 | 11:46 AM

lost

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From: Spring Tx

One reason is that the 2.73 rear is a different animal than either the 3.15 or 3.42, has smaller carrier bearings.The labor involved in properly setting up new gears offsets much of the cost of just changing the complete rear end. Really well qualified rear end mechanics are few and far between. One only has to read the many complaints of improperly set up rear ends, whining, grinding etc.to know it makes sense for the shop owner to recommend the total rear end change.Even the higher non stock ratios are many times put together by professionals and sold as a complete unit.

Jul 15, 2005 | 12:06 PM

CarsRFun

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Drifting

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From: Chesapeake Va

i have 3.42's came with my FRC

Jul 15, 2005 | 02:09 PM

DTE Powertrain

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From: Fort Wayne Indiana

Quote:

2) The 2.73 carrier will not take some of the other ratios.

Quote:

3) The 2.73 carrier has less webbing than for instance the 3.42SP Z06 carrier.

Not entirely correct.. 2 AND 3-series differentials both come from the manufacturer with either 1 or 3-ribs.

Quote:

One reason is that the 2.73 rear is a different animal than either the 3.15 or 3.42, has smaller carrier bearings.

Absolutely incorrect.... ALL 1997 to 2005 Getrag differentials in either 2 or 3-series models have the very same carrier bearing/race sizes for all years of C5 Corvette.

FYI if anyone is interested.

http://www.dynotech-eng.com/dte_c5_diff.htm

Jul 15, 2005 | 02:28 PM

debmwb

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From: Fort Worth Texas

Quote:

Originally Posted by DynoTech Engineering

Yes they do, as we've been performing these types of gear ratio upgrades using the 2-series differentials with outstanding durability success for 3 years now. The 2-series carrier will and has accepted any other gear ratio that's currently on the market when built properly.

Not entirely correct.. 2 AND 3-series differentials both come from the manufacturer with either 1 or 3-ribs.

http://www.dynotech-eng.com/dte_c5_diff.htm

Yep....forgot about that....you are entirely correct! I will also add that your shop is one of the few performing these upgrades that I have heard nary a complaint about!

Jul 15, 2005 | 02:52 PM

lost

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From: Spring Tx

Kudos to DTE, their website has got to the best I've seen for Corvette owners.Absolutely no question is left unanswered...Wish I'd checked them out when I was in Cincinnati last month....