Suburban 3/4 Ton 4WD V8-305 5.0L (1986)
Fig. 5 Speedometer calibration chart
Remove instrument cluster assembly as outlined.
Plug connector from speedometer calibration service kit into rear of cluster, Figs. 3 and 4.
Momentarily touch connector leads across battery terminals noting the following:
a. Service kit connector should be used a maximum of 10 times.
b. It is not necessary to momentarily energize calibration system if speedometer has been previously calibrated.
Refer to the calibration chart Fig. 5, to determine which pins to remove from the calibration clip, Fig. 3, noting the following:
a. The rectangular end of the clip is the top, and pins are numbered 1---8 from top to bottom.
b. Remove proper pins by bending them back and forth with long nose pliers, taking care not to bend adjacent pins.
Insert calibration clip into rectangular slot in rear of cluster, Fig. 4, ensuring pins engage proper holes.
Reinstall cluster and check system operation.