Exhaust manifolds

I have a 1999 F250 SD. Three years ago I had the exhaust manifold gaskets and bolts replaced due to a leak. It is leaking again. Now they tell me the manifolds are rusted and need replaced. I've never heard of a manifold rusting out. Anybody else heard of this? Smells fishy to me.

I have seen exhaust manifolds that rusted in the area of a leak that were so pitted that new gaskets would not allow them to seal. If you can't do the work yourself, let them know that you want to keep the old ones after the repair and see the damage yourself as well as the fact that you are taking them to the scrap yard to get salvage money from them (even if you aren't). Having them know you want to see them might change their tune if they are trying to scam you. If they do change their tune, run don't walk to a different shop.

I'm a licensed mechanic and I'm not saying they are trying to rip you off, but i have done a lot of these, and its usually a common practice to actually replace the manifolds while they are off and the studs are being replaced because they are broken off in the head. usually 75% of the ones i do the manifold is cracked at the back, right where the rear studs are broke off. i try to avoid reusing the old manifold its even worse on the mid 2000 ford truck engines. because some times the don't seal up properly. I've had to redo this job a few times before, customer trying to save money and they end up paying again to get new manifolds.

also what kind of gaskets did they use. i always use the Ford steel ones with new manifolds, but if reusing the old manifold its better to use the metal graphite ones, they will form a bit better to the old manifold and seal a bit better, no guarantees.