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HOMESERVICE MANUALSCHEVROLET1987HI-CUBE 6.2 J, 475/M40REPAIR AND DIAGNOSISEXTERNAL PAGESDIFFERENT CARSECTION 41 (DRIVE AXLE RATIO IDENTIFICATION)IDENTIFICATIONAXLE RATIO & IDENTIFICATION

1987 Chevrolet Hi-Cube 6.2 J, 475/M40

Axle Ratio & Identification

1987 Chevrolet Hi-Cube 6.2 J, 475/M40SECTION Axle Ratio & Identification

WARNING: This page does not describe the selected car, but rather 31 other vehicles, including the 1993 Oldsmobile Bravada, 1993 GMC Yukon, 1993 GMC Vandura Special, 1993 GMC Vandura, and 1993 GMC Value Van. However, it is still accessible from the selected car via links, so may be relevant.

ASTRO & SAFARI FRONT AXLE RATIO IDENTIFICATION

Application & Code		Ratio
7.625" Ring Gear
SKY, ZYD, ZYH		3.42:1
SKZ, ZYF		3.73:1

"C" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

8.5" Ring Gear

XPN ⁽¹⁾, XRT ⁽¹⁾

3.08:1

UUS, XPF, XPJ ⁽¹⁾, XPM, XPP ⁽¹⁾

3.42:1

UUU, UUW ⁽¹⁾, XPG, XPK ⁽¹⁾

3.73:1

9.5" Ring Gear

RYA, RYF ⁽¹⁾, TXW, TXZ ⁽¹⁾

3.42:1

RYB, RYG ⁽¹⁾, TXX, TYA ⁽¹⁾

3.73:1

RYC, RYH ⁽¹⁾, SJA, TXY, TYB ⁽¹⁾, XRC

4.10:1

RYD, RYJ ⁽¹⁾

4.56:1

10.5" Ring Gear

RYK, RYN ⁽¹⁾

3.42:1

RYL, RYP ⁽¹⁾, SJM, SZX ⁽¹⁾

3.73:1

RYM, RYR ⁽¹⁾, SJN, SJR ⁽¹⁾, SJT, SJW ⁽¹⁾

4.10:1

RDP, SJP, SJS ⁽¹⁾, SJU, SJX ⁽¹⁾

4.56:1

11" Ring Gear (UXG)

4.63:1

⁽¹⁾	With positive traction, limited slip differential.

"C/K" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

10.5" Ring Gear

XUA, XUB ⁽¹⁾, RZJ, RZM⁽¹⁾, SFB

3.73:1

SFF ⁽¹⁾, SFJ, SFM, SJM, SZZ

3.73:1

RZK, RZN ⁽¹⁾, SFC, SFG ⁽¹⁾, SFK, SFN ⁽¹⁾, SFX

4.10:1

SFY ⁽¹⁾, SJW ⁽¹⁾, SZW ⁽¹⁾, SZS, XUC, XUD ⁽¹⁾

4.10:1

RLK ⁽¹⁾, RLZ, RZL, RZP ⁽¹⁾, SFD, SFH ⁽¹⁾

4.56:1

SFL, SFP ⁽¹⁾, SFZ, SGA ⁽¹⁾, XAF

4.56:1

⁽¹⁾	With positive traction, limited slip differential.

"G" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

8.5" Ring Gear

RKF, RKG ⁽¹⁾

3.08:1

RKH, RKJ ⁽¹⁾

3.42:1

RKK, RKL ⁽¹⁾

3.73:1

9.5" Ring Gear

RKM, RKU

3.23:1

RKX, RKZ

3.73:1

RKY ⁽¹⁾, RLA

4.10:1

RKR, RKW ⁽¹⁾

4.56:1

10.5" Ring Gear

RMU, RMX ⁽¹⁾, SYK, SYP ⁽¹⁾

3.42:1

RMW, RMY ⁽¹⁾, RMA, RMC ⁽¹⁾, SYL, SYR ⁽¹⁾, XSX, XSZ ⁽¹⁾

3.73:1

RLW, RLZ ⁽¹⁾, RMB, RMD ⁽¹⁾, SYM, SYS ⁽¹⁾, XSY, XTA ⁽¹⁾

4.10:1

RMG, RMJ ⁽¹⁾, SYN, SYT ⁽¹⁾, XTB, XTC ⁽¹⁾

4.56:1

⁽¹⁾	With positive traction, limited slip differential.

"K" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

8.5" Ring Gear

UUX, UUY ⁽¹⁾, XRA ⁽¹⁾, XRD, XRF ⁽¹⁾, XPR, XPU ⁽¹⁾, XPY

3.42:1

UUZ, UWA⁽¹⁾, XPC, XPS, XPW⁽¹⁾, XPZ, XRB⁽¹⁾, XRH⁽¹⁾, XRG

3.73:1

XPX ⁽¹⁾, XPT

4.10:1

9.5" Ring Gear

TXN, TXS ⁽¹⁾, RYS, RYX ⁽¹⁾

3.42:1

TXP, TXT ⁽¹⁾, RYT, RYY ⁽¹⁾

3.73:1

TXR, TXU ⁽¹⁾, RYU, RYZ ⁽¹⁾

4.10:1

RYW, RZA ⁽¹⁾

4.56:1

10.5" Ring Gear

RZB, RZF ⁽¹⁾

3.42:1

RDM, RZC, RZG ⁽¹⁾, SZY

3.73:1

RZD, RZH ⁽¹⁾, RDN, RDR ⁽¹⁾, RLG, RLH ⁽¹⁾, XPT, XPX ⁽¹⁾

4.10:1

RDP, RDS ⁽¹⁾, RLJ

4.56:1

⁽¹⁾	With positive traction, limited slip differential.

"K" SERIES FRONT AXLE RATIO IDENTIFICATION ⁽¹⁾

Code

Ratio

ZHW, ZLS

3.42:1

ZBL, ZGT

3.73:1

⁽¹⁾	No other information is available from manufacturer.

"P" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

10.5" Ring Gear

SDK, SGB, SDN ⁽¹⁾, SDR, SDU ⁽¹⁾

3.73:1

SDL, SDS, SDX

4.10:1

SDM, SDP, SDT, SDW ⁽¹⁾, SDY, SFA ⁽¹⁾, TJT, TJX

4.56:1

TJY ⁽¹⁾

4.88:1

SDZ, UWU

5.13:1

11.0" Ring Gear

UWH

4.63:1

TFT, TFU, UWJ

5.13:1

⁽¹⁾	With positive traction, limited slip differential.

"S" & "T" SERIES REAR AXLE RATIO IDENTIFICATION

Application & Code

Ratio

7.5" Ring Gear

UBA, UBB ⁽¹⁾, XUF, XUG

3.73:1

UBC, UBD ⁽¹⁾, XUH, XUJ ⁽¹⁾

4.11:1

7.625" Ring Gear

TFY

2.73:1

TFZ ⁽¹⁾, TGA, TGB, UBJ, UBR, USZ, UTA, UWG

3.08:1

SZM, SZN ⁽¹⁾, TBS, TGF, TGH ⁽¹⁾, UBK, UBL ⁽¹⁾

3.42:1

UBT ⁽¹⁾, UTB, UTC ⁽¹⁾, UUL ⁽¹⁾, XAZ ⁽¹⁾

3.42:1

⁽¹⁾	With positive traction, limited slip differential.

"T" SERIES FRONT AXLE RATIO IDENTIFICATION ⁽¹⁾

Code

Ratio

SKY, ZXC, ZYD, ZYH

3.42:1

SKZ, ZYF

3.73:1

⁽¹⁾	No other information is available from manufacturer.

RENDER: 1.0x

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.
• Brakes feel soft, pull hard to one side, or make grinding noises.
• The engine overheats, stalls repeatedly, or misfires under load.
• You are missing required tools, torque specs, or safe lifting equipment.
• You are not confident in the next step or safety outcome.

Safety Warning

Axle Ratio &amp; Identification

Use the Manual With the Right Hardware

When to See a Mechanic

Axle Ratio & Identification