2001 5.9 ISB Cummins Exhaust Manifold

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Well-known member
Oct 26, 2009
I have one in my 02 Journey that's cracked. I understand that this is common with these manifolds in this year. I also understand that aftermarket ones that are redesigned are available and better. I did a quick search on line and the ones I see are all for Dodge trucks, the RV manifolds are different. Any info on who would carry ones for RV's?


Maybe this place can help you,

Maybe a call to them, and maybe they are all the same?
Mine had the same issue. I only replaced the half that had the crack. I ordered it through my local truck center. The cost for the half was around six hundred cdn. This included the gaskets, and new hardware including the turbo bolts and nuts. The old turbo bolts were the hardest thing to remove. We had trouble even breaking them off. The only way we could get at them was from below with a really long set of extensions. I even broke one of the extensions. Luckily we got all the manifold bolts out without breaking any. Took me and my mechanic friend a good six hours to change the manifold. It was a bit of a pain.
  It probably can be welded back up if you can find a willing and knowledgeable welder. Our 8.3 cracked in several places and was welded back together. We tossed it into a fire pit until just turning red, then welded it one crack at a time and returning it to the fire between welds so it doesn't cool off too much. When finished we tossed it back into the fire and came back the next day after everything had cooled down. Basically preheating and postheating, used a high nickel rod or cast rod, I'm not sure which since I have both on hand.
Utclmjmpr said:
With all that heat and cool, plus welding, I'm sure you had to also resurface the manifold.>>>Dan

yes I did, cost me $40. While I was at it I made it into a three piece manifold instead of one piece.  The heat cycling of the stock manifold during normal operation is partly responsible for it shrinking. That led to stress on the bolts and cracking. Another good reason for allowing temperatures to stabilize before shut down.
Took a look at the manifold from the ground, can see two cracks, one completely around the manifold. Although welding cast iron is possible I can't see doing it with chances of it happening again. I guess this manifold wants to shrink and the more heat it sees running aggravates the problem. I tow an enclosed car trailer with this so I would expect to see more heat that running without the trailer. Took another look online and two aftermarket manifolds (BD and DPS) are available for around 400$. They are made from much better material and also beefier & reinforced and have an expansion joint in the critical area! For the agg it takes to R&R this, not doing it twice so I will buy one of these and do the swap. The new ones are also contoured for better flow and performance. On removing the old bolt, was told to run the motor up to operating temp and then start the disassembly. Can only hope is goes smoothly, RV has only 56K on it and from what I can see, all the bolts look in good shape.

BTW, I had no idea it was cracked! One day a friend of mine was standing near the RV when I started it cold, he knew right away it was cracked by the light ticking sound it made. Once the manifold warms up the cracks tend to close up somewhat so you just don't hear the exhaust leaks! Now that I know it is cracked, it makes senses that I felt it was down on power and mileage but a small amount caused by the cracks.

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