I was talking to someone that bought their GMC last year. LP tank was low on a cold day. Went to a place to get it filled. Seem that the person over filled the tank. And they didn't know it. As they traveled South into warmer outside temps. The LP didn't have room in the tank to expand. They ended up stopping at another LP fill location to find out why they smelled LP. We too should have some knowledge of the proper procedure. So we can observe that it's done properly each time. As it's our lives on the line here. I always observe during fills. Just never thought that an untrained person would be sent out to do the job. Bob Dunahugh 78 Royale Iowa