Is a performance chip worth it?

That I would have to check on. I did some research and considered buying an exhaust from an online store. The trouble is I don't have a lift or a welder, so I just had the dealership do it when I bought it. I have the old system, so I can see. The specs say a 8HP gain, and 1-2 MPG gain. I can say the HP is true. Plus is sounds great. The dealer charges about $100 more than if you can do it yourself: http://trdparts4u.toyotaofdallas.com/scripts/prodView.asp?idProduct=-9567

 

Is the TRD cat back only available for 05+?

 

No official trd cat back exhaust prior to 05'. This site looks like it has some after market exhaust systems y hat would give the same performance: http://www.carid.com/toyota-tacoma-exhaust-systems/