I was messing with the turbo trying to figure out why my truck hasn't been running like it should. I had my wife in the truck to hit the throttle while I watched the turbo. That's when I saw a puff of black smoke out of the exhaust manifold.

There's a crack near the center, but the manifold was too hot for me to get my finger in there to see (feel) how bad it is. It doesn't seem to be real bad, I can see about an inch of a crack but it goes back under the manifold toward the engine so I don't know just how bad it really is right now.

Is this common? What's the best fix? Stock manifold or an aftermarket? And the biggest question...how much will this cost me?

 

It's actually a relatively common occurrence. You could replace it with a stock manifold, but you won't be happy with the price of a new one, and why take chances with a used one? An aftermarket 3 piece will set you back about $475 as I recall...

 

how many miles? if you intend to keep it forever then go with a 3 piece aftermarket,otherwise replace it with stock....my original has 230000 miles on it

 

Thanks for the ebay link John. I bought the stock one for $89.

Do I have to remove the turbo to change the manifold?

Any tricks, haven't had one off yet.

 

Mine went out at about 110k and I noticed it one day when I got on the throttle hard with the adrenaline on 10 from a stop and I saw the smoke come out from under the hood, so I opened the hood and sure enough a nice big crack.
It was a pretty easy fix probably took a couple hours and you don't have to take off the turbo. I bought a used one for $100 and a new set of gaskets.

 

I understand they're a special cast iron. If mine starts leaking, I'm going to try to find what welds easily. There's some pretty interesting ideas TIG welding cast iron w/silicon bronze and an aluminum bronze...could be applied to cast iron cylinder head repair.

 

I would think that silicon bronze might be iffy at the high egt's these see. If it'll survive 1400, that might be a slick repair.

Personally, I wouldn't go stocker. The aftermarket 3 piece sets are thicker. The three piece design resists cracking, but the thickness holds in heat that helps spool your turbo. It was a barely perceptible change when I put mine on. Mostly just smoother, but I know it won't warp and crack.

Were I to do it again, I'd look VERY seriously at the stainless steel manifolds. Very resistant to warping, tweaking. And INCREDIBLY good at containing heat. Not very thermally conductive at ALL. Free efficiency and power, lower underhood temps, quicker and more spool. Weldable, and ooo soo shiney!

 

I would love to go aftermarket.

But, too many other things need attention around here besides the truck.