Axle Ratio Identification

AXLE RATIO IDENTIFICATION (CAPRICE SEDAN, IMPALA SS SEDAN)

Application

Teeth: Ring Gear/Pinion

RPO Code

Axle Code

7 5/8" (2.93:1)

41/14

GW9

2GF, 2GG

8 1/2" Ring Gear

2.93:1

41/14

GW9

⁽¹⁾ 2LQ, 4ZB

3.08:1

40/13

GU4

⁽¹⁾ 2LL, ⁽²⁾ 2LW, ⁽¹⁾⁽²⁾ 2LX

3.23:1

42/13

GU5

⁽¹⁾ 2GU, ⁽¹⁾ 2LS, 2LT

3.23:1

42/13

GU5

⁽¹⁾ 2LU, ⁽²⁾ 2LY, ⁽¹⁾⁽²⁾ 2LZ

⁽¹⁾	Limited slip differential.

⁽²⁾	Police equipment.

AXLE RATIO IDENTIFICATION (CAPRICE WAGON, ROADMASTER WAGON)

Application

Teeth: Ring Gear/Pinion

RPO Code

Axle Code

8 1/2" Ring Gear

2.56:1

41/16

GM8

2YN

2.93:1

41/14

GW9

2YF, ⁽¹⁾ 2YG

⁽¹⁾	Limited slip differential.

AXLE RATIO IDENTIFICATION (ROADMASTER SEDAN)

Application

Teeth: Ring Gear/Pinion

RPO Code

Axle Code

8 1/2" Ring Gear

2.56:1

41/16

GM8

2GC, ⁽¹⁾ 2GQ

2.93:1

41/14

GW9

⁽¹⁾ 2NS

⁽¹⁾	Limited slip differential.

Fig 1: Locating Rear Axle Identification Codes

Courtesy of GENERAL MOTORS CORP.