Much less work that having to revert any mods to get the dealer to try and figure out and replace. Good job!

Amazing how the lining can delaminate and be pushed like that, not surprise though due to the pressures involved. Even better that it didn't FAIL catastrophically on you.

Glad it has been resolved and great to know of such outcomes.

 

So to recap and make sure i have this right. the problem was the hose. it was actually producing the hissing sound? i've got an 06 with 170k on it with out this issue but my fathers 08 with 90k just started this hissing sound yesterday. we can tell which hose it is because the noise is much louder in one than the other.

think we should just replace it?

 

This was a very helpful thread as I just had the same thing happen. Truck is still under warranty so i just had the line replaced which sure enough had the Teflon lining protruding into hydra boost body. However............
On the way home (3 hours from dealership) the truck had an issue. While driving I heard the alert tone and looked down to see lots of lights and a full messages display. I also had no response from the throttle. I pulled over and started to record everything. Engine light, ETC light, "service four wheel drive" light, "trailer disconnected" message, "service four wheel drive" message. I was not pulling a trailer and was not in four wheel drive. I pulled the codes p2299 (brake/throttle pedal position) and u00001 (main bus. Comm.)
Dealer suggested it was likely the result of a glitch from the Teflon lining remanents in the hydra boost unit.
Why see notifications about the trailer and four wheel drive system?

 

To me it sounds like the techs must have pulled apart a harness in and around the cross over near the booster. Teflon in the Hydro boost will not be sensed, the truck isn't that smart.

 

Does that teflon liner serve a purpose in the hoses? My 03 is hissing now and I am trying to decide on buying a new hose or pull the liner out.

 

I am having a similar issue with my truck. Except that the hissing sound is heard at the exact opposite time - the sound only happens when I turn the steering wheel. If the wheel is centered, no hissing can be heard. Do you think the hose could be causing the hissing sound? If I take this hose off to check the Teflon lining, can I put the hose back on and keep driving the truck? I am asking since my local Dodge dealer does not accept returns on special order parts so I don't want to order the hose and end up not needing it.

 

Same here. Noticed it just a few weeks ago.

 

I took both hoses off the hydro boost and neither one had the Teflon liner sticking out of it. Does anyone know what else I can look at to fix the hissing issue?

 

I know it's a long shot to ask since it's been 6 years but did you ever resolve this problem? My trucks doing the same thing