my truck is the early 98 12 valve, the smog people tell me that new it did have a cat. I did not buy it new. In looking for an after market cat I can't seem to find one thats calif legal. I am told there is do such thing. They pretty much say 49 state legal, Calif the exception. Also it seems that for the most part they won't even sell to a calif address. The information that I find states that now you can't even buy a used one and if you do you not allowed to install it on your truck. In talking to one of the larger dodge dealers here, Moss bros. The parts dept states that they can no longer get one. and that that part is discontinued. It is interesting that the smog people tell me that my truck passes the test it just needs a cat actually all they need is the number off the cat that corresponds to my year of manufacturing. Ant way thanks for the help I have always had good luck solving problems with this web site