Here's why your up-pipes leak.
 

Well, having the transmission out of my brother's truck to replace a torque convertor seal is the perfect time to replace those pesky, problematic, and downright RETARDED up-pipe seals......I told him to just buy the pipes too since the combined cost is only about $75.

Here's an ok picture of the wear that occurs on the pipes. This is caused by the 5/16" wide donut moving up and down during heat cycles. There is nearly .010" wear here....it's gouged pretty good. There is NOTHING sealing the donut portion of the pipe (closest to the turbo) except a tad bit of a squeezing of the donut when the flanges are bolted down...puts a little pressure around the pipe. But, once the pipe gets worn, there isn't enough diameter left and the seals leak between the pipe and the seal. Great design, I tell you what.

https://www.ford-trucks.com/user_gal...id=154003&.jpg



Here's a comparison between a 4" exhaust pipe and the up-pipes......


https://www.ford-trucks.com/user_gal...id=154004&.jpg




Enjoy!

Im going to try to use SB chevy manifold gaskets on mine. They are much thicker, i can't afford dem fancy bellows, so ill try the cheaper route.

I can see how that might cause a little leak. :eek:

is it true that leaky up pipes can lead to loss in MPG?

Dan seems to think so and I truly believe it as well.

Would be a good thing to take a look at the next time I'm rattling around in there. An interesting experiment, perhaps, to see if my MPG increases with a little bit of modification if I find mine are in the same shape as those in the photograph.

Have fun getting them out!! It's a lot easier to do with the tranny out versus just taking the turbocharger off...besides, then the "y" junction into the turbocharger is not disrupted so everything goes back together nice and smooth. On a side note, a 4" downpipe is a real PITA when taking off that passenger side up-pipe. BF prybar to the rescue!!

Well...here pretty soon i'm installing a brand new 4 or 5" (haven't decided yet) stainless exhaust system with new downpipe...would it be more accessible then? Do you really have to remove the tranny?

On a side note - you guys wll probably know. I want to run the exhaust out the rear but am running into issues with ROOM, especially now that I have my 35" spare mounted beneath the bed. The current thought is that I might be able to reverse one of my shocks in the opposite direction, diagonally, to allow the exhaust to pipe through there. Why did Ford do that, anyway? Every other truck i've seen has the shocks installed in opposite directions. Anyways looked and it seems as though the shocks are just held onto the leaf with a few removable clamps. Ideas? :-hijacked

my pipes are leaking also, and the rear manifold to head on both sides at#4 and #8
took to ford for 5year 100k warranty and they ordered parts for next week. also sounded like they were hoping for a rear main seal at same time. I certainly hope it would help my mpg only around 15. just got this '03 7.3. thought it would get better than my 97 psd which gets 15-16 modified.

also do you suppose a bigger exhaust with less back pressure these seals would last longer. ford also told me there is programmer software already in my truck and would leave it in if i wish. should I have them 'blow' it out and get my own programmer so I know what I'm running?

Lisa you do not need to remove the tranny. However in order to say that, you do need to remove the turbocharger and it's pedestal, and you will need to contort into some crazy positions to work on it back there which im sure you are flexible enough to do. I had to remove my downpipe as well to get to the lower connections at the right manifold. My down pipe would not come out of the connecting pipe behind it, so i had to cut the downpipe halfway up, now i have two half-downpipe pieces, it makes it ridiculously easy to install and remove it single-handedly. I used an accu-seal clamp to reinforce and hold it together. If you bother to replace the pipes, just go with the bellowed IH version, and get it done with. This isn't a job you want to do more than once. My pipes are on the scrap metal pile as well, they looked just as bad or even worse than those pipes.