OEM Exhaust Manifold Studs

[Ncostello]

Geno's advertises a stud kit for exhaust manifolds. But it specifically says not for the OEM manifold on the 12V trucks. Anyone know of a good source for studs to be used with a stock 12V manifold? I suppose I could just take the stock bolt length and add maybe a 1/2 inch of thread to that and buy generic studs. But a kit would make life easier. At the least I need new bolts. I'm going to remove the manifold to replace the gasket and re-using the existing bolts isn't going to happen.

 

[Bill Lins]

The OEM manifolds are notorious for shrinking- may well be why studs are not recommended. Better a bolt head snap off than the head breaking at the stud. You might give strong consideration to getting a multi-piece replacement manifold.

 

[Shadrach]

The manifold is held to the head with bolts. They are available from any Cummins Dealer or Distributor and are not expensive. Regular bolts or studs won't take the heat.
David

 

[Ncostello]

So if I use a 3 piece aftermarket manifold...go with a stud kit? And if the OEM manifold appears fine (no shrinkage, cracks etc) use new OEM bolts?

 

[Shadrach]

In most cases the OEM bolts will not work due to the design of the after market manifold, also they will likely be too long. Look at the two manifolds and you will see what I mean. The original style requires long bolts whereas the replacement can get away with shorter ones. Studs help with the initial hanging of the manifold as well. If you are buying new see if they come with mounting hardware.

David

 

[the2finger]

I just put a diesel power service 3 piece manifold on my 92. They sent the manifold with allen head cap screws. I got a stud kit off ebay and used it on the outer exhaust ports but you have to use the gawd awful allen heads on the port at the turbo, no room for the nuts on the studs or a regular bolt either.