Car acts like it shifts down at about 55 Mph. If you let off the gas and back on it will go back to Overdrive.
If it's downshifting early or too much, adjust the cable that goes from the transmission to the throttle body. It should be located beside the throttle cable on the bracket by the throttle body. You will want to adjust it so that less exposed cable is showing. A small adjustment will make a big difference, so go one click, test drive, and repeat until it operates correctly. (Picture is of an aftermarket intake, but the cables are the same, circled is the cable that your should adjust, the one on the left)
I agree. Should be the overdrve cable.
how much are you pushing on the gas? when you give it gas at 55 its going to drop out of overdrive and into the previous gear for acceleration. overdrive was not meant for speed but instead, it was intended to drop the RPM's at a highway speed to improve gas mileage, and make it easier on the car.
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