My 1990 sierra 4x4 wont go into overdrive. The engine just revs up. Other gears work fine.
Your overdrive band internal to the transmission might be burned up. How is your fluid, dark and black? Have it checked out by a recommended mechanic or transmission expert to diagnose your problem. If in fact it is the band, your looking at a rebuild since you have to tear into the trans to replace it.
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