I have a 96 jeep cherokee. I need a new exhaust manifold and my mechanic agreed I can provide the parts to save some money. Which is better, stainless steel or cast iron? I understand iron rusts, but that’s not such a big problem in Colorado. I read that stainless steel expands & contracts a lot more so seals can split. Cast iron sounds better-and cheaper. I don’t expect to keep this old jeep more then a couple more years, so I don’t want to spend a fortune, but the labor cost is quite a bit so I want a part that won’t go bad in 6 months either.
I’d replace it with a stock factory part (cast iron), has worked great for decades.
Go with cast iron. Costs less and with stainless steel, normally a header, you will also need to add a flex coupler to prevent these aforementioned cracks. That adds more parts and more labor. If you don’t plan on keeping it forever and don’t need or desire a performance header, the OE cast iron will suffice.
If the original looks like tubing, it’s steel or stainless. If it looks like it is all rusty and rough and heavy it is cast iron. Get the one that looks like the one you have. If it was steel, you probably can’t get an iron one.
Stainless looks prettier. May perform better with a custom exhaust system. That’s it for advantages.
Unless you’re under 30 and/or a hot-rodder it seems you’re not interested in those things.
Cast Iron is the perfect material.
Stainless Steel is technically superior in many regards as a material, and the part will probably be a “header” rather than a “manifold”, but it’s a totally unnessesary expense in your application. You’d spend lot smore cash and get zero benefit.
Stick with a cast iron original. The only issue I can see here is why the manifold cracked. If it’s cracked due to severe overheating then there may be more serious engine issues unaccounted for.
The Jeep 4.0 exhaust manifolds,both cast and welded, are prone to crack. The Dorman after market part seems to be a satisfactory replacement.