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Instruments - Tachometer Accuracy

Group Ref.: Chassis/Body Electrical

Bulletin No.: 368305

Date: February, 1994

INFORMATION

SUBJECT:
TACHOMETER ACCURACY

MODELS:
1992-94 CHEVROLET AND GMC C/K TRUCKS WITH A TACHOMETER (RPO U16)

The tachometer used in C/K trucks with RPO U16 is calibrated so that the first mark shown on the tachometer display is 500 RPM. At idle, this may leave the impression that engine speed is too low or that the tachometer is inaccurate when neither is the case.

If engine idle speed is normal and the tachometer appears to be correct at engine speeds above idle, the tachometer is operating as designed and no attempt should be made to alter the vehicle tachometer reading at idle.