[sambam]

Welcome to the forum. This is the best place to get answers for questions regarding your Montana. As you can see in my sig, I also have a 3455SA. It is one of the heavier ones in the Montana line. I use a dually, but there are those on this forum that pull this kind of weight with 3/4 tons. The pin weight is the biggest issue for 3/4 tons, but you need to look at all the weights with your camper loaded for travel, GCWR, GVW, axle ratings. I would strongly recommend a diesel. Depending on the year of your 5er, the front cap may be contoured to allow a short bed without the slider. I suggest that if you go short-bed, get a slider. Better to have one and not need it. Pull-rite makes a popular slider, but there are others. Also, while you're at it, ditch the E-rated ST tires if they're still on there and move up to a G. You'll be glad you did. Best of luck with your decisions. You'll get plenty of good advice here.