So let me see if I can describe this right since there are actually two things. Lately at slow speeds when the cruise control is engaged, it seems like the speed fluctuates + or - 1 mph. Well yesterday, I took the truck to Midas to get an alignment done and the cruise worked fine at 55mph. I got the truck back and now it doesn't work. I don't blame them because they only did an alignment and didn't mess with anything. I was there so I know the work they did. I checked the fuse inside the truck and it was fine. I'm not very well versed on cruise control problems since I've never had to deal with it. Thoughts?? Second, the crankshaft position sensor is bad so I'm not sure its affecting this or not. When I'm driving at 55 mph down the highway, I'll let off the gas to coast to a stoplight. The truck gradually will slow down and downshift, but my RPM's stay around 1800. They will lower when I hit the brakes, but I thought it was odd. Could it be the TPS or something else? Any help is appreciated.