I can't speak for the 3600 but a front sway bar will definitely help a 3100...for all the reasons I'm sure you already understand and expect. My only suggestion would be to not be penny wise and pound foolish. A good one will cost more, but go ahead and spend the $ for it. There are cheap ones out there that I think (just my opinion) might not be very effective at all. Look at diameter, etc. When one side of your front axle moves, you want that movement transmitted to the other side with as little loss as possible.
As for the rear sway bar, I know others may have differing opinions, but I wouldn't get one. I'd spend the money I saved on this to get a good one for the front. Good luck!
