Q: fluctuating idling and slippage

asked by on May 02, 2016

Truck started acting as though the transmission was slipping, going down the highway it would fall a gear or would up shift hard but now when it idles it will fluctuate high and low rpms. Doing some research online found blogs that say it could be the master airflow sensor however nothing looks wrong with it found a crack in the radiator so replace the radiator still idling high and low. Possibly going to replace the master airflow sensor but after that I have no idea what to do

My car has 174000 miles.
My car has an automatic transmission.

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