C5 Tech Corvette Tech/Performance: LS1 Corvette Technical Info, Internal Engine, External Engine, Tech Topics, Basic Tech, Maintenance, How to Remove & Replace
Sponsored by:
Sponsored by:

Differential Gears

Old May 16, 2013 | 10:44 PM
  #1  
memmer's Avatar
memmer
Thread Starter
Burning Brakes
10 Year Member
 
Joined: Aug 2010
Posts: 1,148
Likes: 22
From: Portland OR
Default Differential Gears

Is it very difficult to change rear end gears from 3.15 to 2.73.
Fred
Reply
Old May 16, 2013 | 10:51 PM
  #2  
NukeC5's Avatar
NukeC5
Melting Slicks
 
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
Default

Its rare that someone would want to do that. Are you thinking fuel economy?
If you pick up a complete diff, its not complicated, but a bit of work. If you're talking about replacing the ring and pinion in your existing diff, your going to need a little expertise and several other refresher items (seals and stuff) as well.
Reply
Old Jun 21, 2013 | 04:40 AM
  #3  
FiberglassFan's Avatar
FiberglassFan
Melting Slicks
10 Year Member
 
Joined: Nov 2004
Posts: 2,275
Likes: 6
From: Lake Oswego, Near Portland Oregon
Default

...and here I am wanting to go shorter ratio than my 3.15!!
You will gain a tiny amount of maximum fuel economy, but loose acceleration at all times, and torque when on hills..Think of going southtbound on the I-5 out of Portland in the Terwillerger Curves, the long uphill..you might have to leave 4 th to keep the load in the cam range of the engine. With 3.15 it is is no sweat.

Yeah, I'm in the Portland area too!
Reply
Old Jun 21, 2013 | 04:48 AM
  #4  
FiberglassFan's Avatar
FiberglassFan
Melting Slicks
10 Year Member
 
Joined: Nov 2004
Posts: 2,275
Likes: 6
From: Lake Oswego, Near Portland Oregon
Default

C5 Gear and final drive ratios

M6 >R&P 3.42 >Final drive ratio
1st Gear 2.66:1 =9.0972:1
2nd Gear 1.78:1 =6.0876:1
3rd Gear 1.30:1 =4.4460:1
4th Gear 1.00:1 =3.4200:1
5th Gear 0.74:1 =2.5308:1
6th Gear 0.50:1 =1.7100:1
Reverse 2.90:1 =9.918:1

Z06/M12 >R&P 3.42 >Final drive ratio
1st Gear 2.97:1 =10.1574:1
2nd Gear 2.07:1 =7.0794:1
3rd Gear 1.43:1 =4.8906:1
4th Gear 1.00:1 =3.4200:1
5th Gear 0.84:1 =2.8728:1
6th Gear 0.56:1 =1.9152:1
Reverse 3.28:1 =11.2176:1


A4 >R&P 2.73 >Final drive ratio
1st Gear 3.06:1 =8.3538:1
2nd Gear 1.62:1 =4.4226:1
3rd Gear 1.00:1 =2.7300:1
4th Gear 0.70:1 =1.911:1
Reverse 2.29:1 = 6.2517:1

A4 Option >R&P 3.15 >Final drive ratio
1st Gear 3.06:1 =9.639:1
2nd Gear 1.62:1 =5.103:1
3rd Gear 1.00:1 =3.150:1
4th Gear 0.70:1 =2.205:1
Reverse 2.29:1 =7.2135:1

A4 CUSTOM with M6 or M12 differential
A4 >R&P 3.42 >Final drive ratio
1st Gear 3.06:1 =10.4652:1
2nd Gear 1.62:1 =5.5404:1
3rd Gear 1.00:1 =3.4200:1
4th Gear 0.70:1 =2.3940:1
Reverse 2.29:1 =7.8318:1

Of course, R&P is "Ring and Pinion"

Your current final drive ratio is 4th Gear 0.70:1 =2.205:1, if you went to the 'stock' A4 economy differential, it would be 4th Gear 0.70:1 =1.911:1 that is quite a big difference in actual feel of how a car responds to throttle.
Reply
Old Jun 21, 2013 | 10:15 AM
  #5  
NukeC5's Avatar
NukeC5
Melting Slicks
 
Joined: Jun 2012
Posts: 3,163
Likes: 6
From: Oceanside California
Default

Honestly, Id keep the 3.15's. They are a great medium between efficiency and performance. You can still get 30mpg on the free way with them. My 3.42's are getting me 28-29. You are not sacrificing much at all economically, and will never save enough on fuel to make up for the cost of the change over.

P.S. Oregon native here too
Reply
Old Jun 21, 2013 | 08:24 PM
  #6  
tiojames's Avatar
tiojames
Team Owner
Supporting Lifetime Gold
15 Year Member
 
Joined: May 2005
Posts: 23,682
Likes: 9
From: Flagstaff Az.
Default

Originally Posted by NukeC5
Honestly, Id keep the 3.15's. They are a great medium between efficiency and performance. You can still get 30mpg on the free way with them. My 3.42's are getting me 28-29. You are not sacrificing much at all economically, and will never save enough on fuel to make up for the cost of the change over.

P.S. Oregon native here too
Before I started modding the vert I was running 3:15s and it averaged a little over 31 at 75-85 on the road. I really doubt you will be happy with the difference in performance for the tiny bit of extra fuel mileage.
Reply

Get notified of new replies

To Differential Gears



Thread Tools
Search this Thread

All times are GMT -4. The time now is 04:45 PM.

story-0
5 Best & 5 Most Overrated Corvette Track Packages of All Time!

Slideshow: The 5 best and 5 most overrated Corvette track packages ever.

By Joe Kucinski | 2026-06-09 12:46:45


VIEW MORE
story-1
Every 2027 Corvette Engine Explained

Slideshow: Every 2027 Corvette engine explained

By Joe Kucinski | 2026-06-09 12:16:31


VIEW MORE
story-2
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette

Slideshow: A Jaguar designer's personal project imagines what a modern front-engined Corvette might look like if Chevrolet revisited the golden age of the Stingray.

By Verdad Gallardo | 2026-06-08 19:53:43


VIEW MORE
story-3
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-4
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-5
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-6
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-7
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-8
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-9
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE