Anyone know the Pipe size that fits the manifolds on a 79 400? Also, In a previous post, I was told there is no donut gaskets used on a 79 F250, but on my truck it sounds like that is where the noise is coming from. any Ideas what the problem might be?

Thanks
Wrecker

1979 F250 Supercab 4x4 Towtruck 400CI 4 Speed

 

I don't think there is a donut on the exhaust on you truck, at least not stock. The pipe should have a flared end on it. Probably 2 1/4" or 2 1/2" pipe off the manifold, my 460 had 2 1/2". Noise coming from that area could be rotted pipe, blown out gasket or a cracked manifold.