i have just purchased a 2005 ram 1500 with the 4.7l v8, it has 155k, and i was just bringing up some of the problems it has to see if its an easy fix or if i should have the dealership fix it, for one the fan speeds 1 and 3 do not work. any ideas? and while going down the highway it makes a grinding noise when it shifts out of overdrive. any ideas? thanks for the help

 

As for the fan speeds, it is either in the control switch **** on the AC controls but more likely the fan resistor block which reduces voltage to control the 4 speeds. The block in under the bash. There are a few threads on this and you can download the service manual for your truck in my signature links listed below.

As for the grinding noise IDK but since you are a new owner and do not know the exact maintenance of this truck, it would be a good idea to replace the trans oil as well as all other fluids.

Welcome to the site BTW

 

and dont just flush the trans you might not like what happens.... pull the pan off and drain it traditionally.... I know the 5.7 trans has 2 filters and when a simple trans flush is performed it moves them out of place...