hmmmmm guys i don't know about this . something tells me its a bad idea to use just one strap considering its for safety . true i have not done this yet to my truck but im thinking i would use both straps . just think maybe some how the tank comes lose on the freeway ? slides out of the one strap and hits the ground ? sparks and gas not the best combo and maybe lose your track to a bad fire . when if you had had both straps it would not have happened just my opinion is all just better to be safe than sorry