Automatic Transmission problems of the 1999 GMC Sonoma

Two problems related to automatic transmission have been reported for the 1999 GMC Sonoma. The most recently reported issues are listed below.

1 Automatic Transmission problem

When in 2 or 4wd on a steep hill in 2nd gear truck does not move. The trans. Will slip and the truck shakes. The owners manual said to use 2nd for.

2 Automatic Transmission problem

When vehicle is in or out of gear engine idles, rpm will flucuate between 1600-3000 intermittently. Dealer ehas replaced idle motor, throttle positioner, new computer , and new software for computer. After several attempts to correct defect, dealer is claiming it is normal.


Other Power Train related problems of the 1999 GMC Sonoma



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