I was driving yesterday and stopped for a red light , then proceeded to take off and the truck was like taking off ibn second or third gear. so i put it in nuetral and then tried again in drive and it did the same thing. At this time the check engine light came on so I got off to the side of the road and checked the trans fluid which was fine. I turned off the truck and restarted it and put it in drive and it was ok but the check engine light was still on. Had the truck scanned today and it is the shift solinoid A. What is involved with this replacement ? Should a buy the solinoid kit or just repace what is broken ? The trans has been maintained with trans flushed evry 50 k miles. Truck has 129k on it now.

Thanks