What Rear End do I have?
Thread Starter
Racer
Joined: Apr 2008
Posts: 381
Likes: 3
From: Santa Clarita So.California
What Rear End do I have?
How do I find out what rear end I have? I know someones going to say it so I'll say it first...Just turn around and look
2:73
3:15
3:42
What are the advantages of the different ones i.e. gas mpg etc...?
2:73
3:15
3:42
What are the advantages of the different ones i.e. gas mpg etc...?
Racer
Joined: Jan 2007
Posts: 293
Likes: 0
From: Maryville IL
Look at your sticker in your glove box for one of the following codes:
G92 Performance Axle Ratio 3.15:1
GU2 Std. Axle Ratio 2.73:1 MXO Auto
GU6 Std. Axle Ratio 3.42:1 Six Speed
A 3.15 gear over the 2.73 is going to help your acceleration a little, but rob your gas milage a little.
G92 Performance Axle Ratio 3.15:1
GU2 Std. Axle Ratio 2.73:1 MXO Auto
GU6 Std. Axle Ratio 3.42:1 Six Speed
A 3.15 gear over the 2.73 is going to help your acceleration a little, but rob your gas milage a little.
Race Director
Joined: Dec 2005
Posts: 11,664
Likes: 15
From: Wellsboro Pa
Look at your sticker in your glove box for one of the following codes:
G92 Performance Axle Ratio 3.15:1
GU2 Std. Axle Ratio 2.73:1 MXO Auto
GU6 Std. Axle Ratio 3.42:1 Six Speed
A 3.15 gear over the 2.73 is going to help your acceleration a little, but rob your gas milage a little.
G92 Performance Axle Ratio 3.15:1
GU2 Std. Axle Ratio 2.73:1 MXO Auto
GU6 Std. Axle Ratio 3.42:1 Six Speed
A 3.15 gear over the 2.73 is going to help your acceleration a little, but rob your gas milage a little.
Thread Starter
Racer
Joined: Apr 2008
Posts: 381
Likes: 3
From: Santa Clarita So.California
I looked at the sticker in the glove box...it had alot of letters and numbers. When I got to the letter G there were two of them one was G90 and the other was G92.? Was that the right sticker?
Le Mans Master
Joined: Sep 2006
Posts: 6,997
Likes: 1
From: Life is a game/Golf is serious. IA
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Melting Slicks
Joined: Mar 2005
Posts: 2,891
Likes: 4
From: North Port Fl
When I bought my car new it came with the 3:15 rear end, but I have since replaced the ring and pinion gears to a 3:42 to 1 ratio. So if you look at my glove box sticker or the tag on the rear end it will tell you I have the 3:15 rear end but I don't. There is a chart in this link that will tell you at what the RPM you should have at a given speed for certain gear ratios for A4 cars. http://forums.corvetteforum.com/show....php?t=1908031 Just check your RPM at certain speeds in high gear and look at the chart. Going by the glove box number will just tell you what came in the car new. In probably 95% of car this will be ok but if the rear end or the gears have been changed this won't be accurate.
Administrator
Joined: Mar 2001
Posts: 368,522
Likes: 24,823
From: In a parallel universe. Currently own 2014 Stingray Coupe.
C7 of the Year - Modified Finalist 2021
MO Events Coordinator
St. Jude Co-Organizer
St. Jude Donor '03 thru '26
NCM Sinkhole Donor
CI 5, 8 & 11 Veteran
With the sticker showing G92, you have the 3.15 rear end ratio. 
Team Owner
Joined: Jul 2006
Posts: 22,200
Likes: 4,187
From: Kannapolis NC
Your code says 3:15, if you want to see if it's been changed do this:
Put your auto trans in 3, drive 75 mph steady and note your rpms and divide by 1000. For example if at 75 in 3rd your rpms are 3150, you have 3:15's. The same will work for an MN6 in 4th gear at 75.
Put your auto trans in 3, drive 75 mph steady and note your rpms and divide by 1000. For example if at 75 in 3rd your rpms are 3150, you have 3:15's. The same will work for an MN6 in 4th gear at 75.
Safety Car
Joined: Jun 2008
Posts: 3,812
Likes: 5,884
Guys,
Its real easy to check your gears. 90% of the time, the RPO will be correct. But to make sure a previous owner didn't change them.. do this:
Put your tranny in the gear that has a 1:1 ratio (3rd for autos, 4th for 6 speeds). Accelerate to 70mph, then check your tach.
2,730rpm = 2.73 gears
3,150rpm = 3.15 gears
3,420rpm = 3.42 gears
Etc, etc, etc. You get the idea.
It worked with my Fbodies, don't see why it wouldn't work with vettes.
EDIT: I see someone beat me to it.
Its real easy to check your gears. 90% of the time, the RPO will be correct. But to make sure a previous owner didn't change them.. do this:
Put your tranny in the gear that has a 1:1 ratio (3rd for autos, 4th for 6 speeds). Accelerate to 70mph, then check your tach.
2,730rpm = 2.73 gears
3,150rpm = 3.15 gears
3,420rpm = 3.42 gears
Etc, etc, etc. You get the idea.
It worked with my Fbodies, don't see why it wouldn't work with vettes.
EDIT: I see someone beat me to it.
Team Owner
Joined: Jul 2006
Posts: 22,200
Likes: 4,187
From: Kannapolis NC
Last edited by 65GGvert; Sep 19, 2008 at 08:17 AM.
Race Director
Joined: Apr 2005
Posts: 10,179
Likes: 2,306
From: Wesley Chapel, FL Las Vegas, NV
Can I just go 37 1/2 mph and divide by 500 instead?
