On my 94 f250 with the 5.8 I have leaks in the manifolds. It is very noticeable and I need to fix it. I originally planned on replacing the stock manifolds with long headers, however I have heard that headers are more prone to leaking then manifolds. I have also been told that manifold leaks are relatively simple to fix once you can get them removed. I also think that with long headers I would have to run a true dual exhaust all the way back and I don't know how big of a deal that is.I'm not sure how the catalytic converter and the oxygen sensors would fit into the system or how difficult the project would be. I also don't know if the performance gain from putting headers on is worth the extra cost and effort as opposed to the manifolds. Any advise would be appreciated! Thanks

 

The cheapest route to go would be to replace your manifolds with new ones. Does your truck have the AIR tubes on the manifolds, or on the back of the heads?

 

Headers are a fairly big job on an F250, longtube headers are one of the best upgrades you could do to a stock motor but the whole exhaust system has to be changed and the air system removed so its a lot of work. Dealing with the O2 sensor is simple in comparison, just install a bung for it in the passenger side header and plug it in.