For trail comms GMRS is great, however you might look at getting one of the mobile units. Transmitting on a handheld from inside the vehicle may result in less than stellar performance.
For emergency comms, as mentioned ham radio takes the cake as far as radio is concerned. If you are really out in BFE alone and have a legitimate concern for safety a PLB device may be a wise investment.
Ham radio isn't just about voice communications, you can use it to track your vehicle (and others) and possibly send a SMS text message to someone's cell phone even if you don't have a cell signal. Though it's a good tool to have in your bag of tricks it helps to stay proficient at it (as with most anything) so it helps to have a license and to be somewhat involved (chat to other hams on your drive to/from work, check into weekly nets, practice manually entering frequencies, etc). Some radios have more of a learning curve than others and if you just toss a radio into your "go bag" and think I will pull it out and use it when SHTF, you are likely to fumble with it and maybe get it half assed working....maybe.
What ham radio should you get? That's up to you, most anything from the big 3 (Kenwood, Icom, Yaesu) would work fine, TYT would be ok, Midland has a ham radio on the market for a great price, maybe BaofengTech. It depends on what options you want/need and what kind of budget you are working with.
Your antenna should be as high on the vehicle as you can live with because in VHF/UHF antenna height is king. Example: A buddy and I were convoying down the highway, I had a 1/2 wave antenna on my fender, he had a 5/8 wave antenna on his roof. He was able to talk to another buddy 30+/- miles away who was also running a 5/8 wave antenna on his roof. I was not able to even hear him. I have another Jeep with an antenna on the roof and I could tell the difference hearing and getting into a distant repeater. With the roof mounted antenna I was on the fringe of the repeaters coverage area, I could hear and get into the repeater most of the time with some scratchiness. With the fender mounted antenna I could neither hear or get into the repeater.