Surging Problem

[Purduegmc]

I was driving my truck tonight and it was running fine. After a half hour drive I pulled into a parking lot and it started surging real bad and died. I thought that it could have been the fact that it was warm, I didn't have a lot of gas in the tank causing it to vapor lock on me. I filled it up with gas and drove it home with no problem until I pulled into the driveway and it did it again. This is the first time that it has done this. Do you think that it could be something else or do you think that it vapor locked on me again. I will say that it doesn't seem to keep up as much oil pressure after it heats up and I am sitting at a light or going slow through town. Thanks for the help.