I think I have a 76 Corvette Rear end that may be a 3:36 or maybe a 3:55 gearing rear end that I am wanting to put in my 67 Corvette that has a 4:11 in it now. Is there any markings on the outside casing that tells me the year and gearing of this rear end? I am a C2 guy and hang out there so if you could PM me or send me an e-mail that would be great. mikes54vet@aol.com Thanks in advance.

 

There are markings on the case, however that doesn't necessarily mean that's whats in it. A quick check is to see how many driveshaft revolutions to one revolution of the tire. That will toss you in the ballpark. To compare, the differential code is stamped on the bottom of the differential carrier housing just forward of the rearend cover. The axle code reads from left to right. The two-letter prefix designates the gear ratio and any other specific information about the axle. The third digit is the plant code. The next three numbers designate the actual day of the year this axle was built (001-365). The seventh digit represents the shift the axle was manufactured on. The last character letter is the Posi-traction source. If a space or no letter follows the shift code, the axle did not originally come equipped with a Posi-traction axle.

Plant Codes:* B = Buick* C = Buffalo* G = Detroit Gear & Axle* K = McKinnon Industries* M = Pontiac of Canada* O = Oldsmobile* P = Pontiac* W = Warren, MI

Posi-Traction Codes:* (-) = No Posi-traction* D = Dana Posi-traction differential* E = Eaton Posi-traction differential* W = Warner Motive Posi-traction carrier

Example: AA G 218 1 E* AA = Axle Prefix: 3.55:1 Corvette Posi-traction axle* G = Assembly Plant: Detroit Gear & Axle* 218 = Day of Year: August 6, 1972* 1 = Shift: First* E = Posi-traction
Source: Eaton

Good luck!

 

Hi

Markings are only markings and not facts.

Best is to measure what you have.

Jack up both aft wheels , mark the tires and turn the main drive draft. Count the turns of the main drive shaft for 1 full turn of both tires.

Rgds. Günther

 

The 76 Rear end is not in a car at this time, it is in my garage on the floor.

 

here we go again...hahaha
http://forums.corvetteforum.com/c3-g...do-i-have.html

 

Not in a car is easy. Count the gear teeth and do some math. 41 tooth ring, 11 tooth pinion== 41/10=4.10

 

Exactly. And that's why it's 4.10 and not 4:10.

 

PM sent.
Mike