why is my 1994 chevy K1500 speedometer innacurate
do you have a different tire size from the factory sticker?
How far off is it? Just like Andrew above asked, is the tire size changed? If so, that is a good reason. If not, it may be a sending unit or the speedometer is going bad. Either have it checked or repaired. It is cheaper that a new one, and having it checked, will tell you maybe your cable is hanging up and needs to be replaced. If you change the cable, use the proper lube on it to keep it gum free.
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