At your request, I went out and checked my truck and van... 2000 F-350, no cat, and no mention of it on the hood stickers, same with the '99 van... however, the van has an item in the exhaust, not in the down pipe, but just after the flanged connection with the down pipe, there's a 8 or 9" diam, about 12-14" long oval shaped canister. Doesn't look like any cat I've ever seen, it's round like pipe, not flat like a cat, (my friends would say the best cat is a flat one....) might this just be a resinator of some type? The muffler is another 4' farther down the van, in the normal place just infront of the jump over the rear axle. Don't tell the ol' man, I'm gonna have to straight pipe the van soon... looks easy to do, glad I went out and looked at it...