alomar721

Hello there I am new and I want to thank you you for any help. I just purchased a 98 ford taurus se with 103,000 miles. Well t make a long story short on the ride home the speedometer went out which in turn odometer as well. when I slowed down and stopped and put in park and started up the car again when I was in drive in wouldnt go fast just just the engie not the trans so i put it in drive not overdrive and went to the next exit and shut it off and tried it again it was fine. I took it in and the service light was that it was a speed senor. How hard is it to change these and if anybody knows how to do it that would be great. I dont want to pay anybody for this which would be $200. I was hoping to fix it my self. Also would this sensor affect the trans ? Sorry for the length. Hope anybody can help me and again thanks.
Scott