Yes, truck bed liner is a sound deadener, and actually, if you read what it comes in, it does say that it's sound deadening etc. It's one of the uses for it.
Main problem with doing this is, a lot of brands have an odor if used on the inside of your vehicle, like on hot days etc..you'll catch whiffs of it for as long as you own the car.
Same thing with the underbody protectant. Some brands smell, some dont.
Want to roll your dice? Heh heh. I'd honestly recomend just going with edead.. It's not going to be that much more expensive once you see how much a can of spray in bedliner actually gets you.
yea ur right, it probly would stink, i thoughti ti would work cuz a local shop rhinoliner-ed the whole inside of a car and it was totaly sound proof (thats what he said anyway)
Some brands smell, some dont.