SPEEDOMETER GEAR CHARTS P273 1979 SPEEDO GEAR USAGE CHART X CAR 4 QT xg TIRE SIZE TRANS 2 S z g 47 6 47 Q ca 0 v A11 M15 A n A11 M20 A IIE ER7sX 14 ER7aX 14 FR70x 14 2 3 M 8 IEI I S E78 X 14 9 3 IIIEI I FR78x 14 E78x 14 FR70x 14 M W IH T E ER78 X 14 3 I IE A11 Ms3 mia FR78x 14 E78x 14 FR70x 14 M33 F C H ER78 X 14 F H A11 M15 A IE A11 M20 A H ER78X 14 E78x 14 FR70x 14 B Z II ER78 X 14 M38 3 Y H ER70 X 14 E78 X 14 ER70 X 14 3 08 M33 y II A 2 1 R7a X 14 I IE FR78 X 14 E78 X 14 FR7O X 14 M33 F C E ER7a X 14 E E H FR78x14 E78x14 FR70x14 M33 F C E ER78 X 14 F T III FR78x 14 E78x 14 FR70x 14 M15 A nm ER78 X 14 A E S FR78 X 14 E78 X 14 FR70 X 14 M20 A III ER78 X 14 A E S ER7a X 14 E78 X 14 FR70 X 14 11 12 8 IEIIIIEI ER78 X 14 I H H 1 1273 X 14 ER78 x14 FR70 X 14 3 23 M33 V E C E78 X 14 II U ER7a X 14 E78 X 14 FRTO X 14 M33 E S III ER78 X 14 E C H FR78 x 14 E78 x 14 FR70 x 14 M33 F E N ER78 X 14 F A I NOTE With Trans Stamped KX With Trans Stamped JD Q With Trans Stamped JC 1987 GENERAL MOTORS SERVICE PARTS OPERATIONS PONTI C 21 4 OOO GROUP 4 28 C REV 7 87