[TABLE=class: tborder, width: 100%, align: center][TR][TD=class: alt1, bgcolor: #FEFEF4]Back from my sibatical. Took a road trip to Montana with a 3 horse trailer. Truck in sig, stock turbo & injectors. The truck had not made a peep till mid trip. In Wy. on most of those I-25 grades the pull would start with 20-30 psi boost and 1000*-1100* EGT and 1-2 min into it, the turbo would start this high pitch whine. I would come off the fuel and stay close to 20 boost & this would decrease the whine a little? I also have a nice exaust manifold leak, tick.. Nothing like a good road trip to work out/ uncover all the gremlins.[/TD][/TR][/TABLE]

[TABLE=class: tborder, width: 100%, align: center] [TR] [TD=class: alt1, bgcolor: #fefef4]Back from my sibatical. Took a road trip to Montana with a 3 horse trailer. Truck in sig, stock turbo & injectors. The truck had not made a peep till mid trip. In Wy. on most of those I-25 grades the pull would start with 20-30 psi boost and 1000*-1100* EGT and 1-2 min into it, the turbo would start this high pitch whine. I would come off the fuel and stay close to 20 boost & this would decrease the whine a little? I also have a nice exaust manifold leak, tick.. Nothing like a good road trip to work out/ uncover all the gremlins. [/TD] [/TR] [/TABLE]

Well, I would not necessarily say its a gremlin. If your turbo is funtioning and fully operational, I do not see a problem. It might the same thing I try and describe to the wife. She gets all skittish when riding in the truck cause she still is not used to hearing all the different noises it makes. The only thing I can narrow it down to is harmonics. There is a sweet spot so to speak with everything. Spooling the turbo up and keeping it in that sweet spot can cause a paculiar noise. Its either that, or you may have some play in the shaft and/or you need to check the bearings.

Tear in the boots causing the whine?

Thanks, I'll be taken the exaust manifold off & will CK turo & bost out for bad boots.

I found a major leak in the entake plenum gasket, its a wonder the truck would make 30psi. I did notice that it would scream when I stomped on it but now its just the turbo wistle.

Well as for noises I had a intake bolt pop out and make whistle / blowing noise...

did the intake plenum gasket have a visable break in it? how loud was the whisle, & did it whine when with a steady throttle position? Thanks Dave.

I had a big leak at the plenum gasket too. The only way I found it was to make a boost tester, hook it up to air, and spray everything with soapy water. Seems like there isn't a 5.9 out there that either has or has had the plenum gasket leak.....

I didnt even need soapy water for mine. It was a huge leak and I wish I would have recorded how loud it was. Tested a buddies truck last night and it has a small leak in the same spot mine did, just under the intake horn. My gasket was kinda discolored a little where it was leaking and the whole thing was very brittle, it just fell apart when I pulled it out. I dont remember a whine with steady cruising but it would scream when I got on it. It was only making 30psi max but now is back up to 38. I vacuumed it all clean and the new one went in really easy, I didnt have to remove any injector lines or anything.

WL mine starts the whine when the boost gets above 20psi. & it gets mod loud and very high pitched, in the range of "E". LOL

Some leaks don't expose themselves until you get high enough in pressure to make it leak. I stripped out one of the intercooler hose clamps (using the impact gun..) and just kinda let it go and all was well until I pulled the trailer and some old lady was in front of me doing 10mph trying to get on the interstate, I floored it to go around her and it blew up at 35psi. I put it back on and all was well, but a similar uh, occasion occured lol and I blew it up again but only partially. It would leak out from under the clamp only at higher boost levels (from what I could hear). The only problem is you can't really get any kind of tester to hold 20+psi. I would just check over each and every clamp for bolt tightness, and same with the intake horn/manifold bolts. Make sure all the boots are on properly as well, not sliding off like mine did in the aforementioned occasion.

Found it, Exaust leak: #6 bolts were missing, the one that will BE a PIA to put back in. I have'nt looked in the holes yet, I hope they're not twisted off. The BA whine, one of the twin banks air horn gaskets has a break in it. AH, on to the next project....ISX any good tricks on putting #6 Ex manifold bolts in? I prefer not to stand on my head! Do you use a crows foot to take to torbo off the Ex manifold? ALL the remaining bolts are in a good penitrating oil soak right now.

I haven't messed with the exhaust manifold so any way you see fit to get the job done is as good as I would be able to tell you. You could take the turbo off easy enough though the studs on the flange aren't exactly fun either.

ISX your supose to relay some GOOD news! The bolts on the turbo, I'll have to stand on my head & dislocate my shoulder to remove them. I've heard that the Ex manifold may shrink/draw up a bit if taken totaly off the engine, so only unscrew the bolt to loosen, then take a pair out to replace gasket & so on. Sounds great but I have my doughts. It's neever that easy. Anybody on here replaced a ex manifold?

Me and a buddy pulled the exhaust manifold off his 04.5 and ended up braking a bolt off in the back. Its been a few years but I dont think it was fun.

OOOOh ya, I can't wait to reach out to those fire wall, #6 cyl. bolts. I just thought of something, I should try to probe the holes FIRST, proceed if no broke off bolts. Thank for the hint whitlighten. Do you recall haven any issues puttin the EX Man back on? Whats YOUR labor rate?

Dave, when I had the head off of mine I pulled the manifold and put new gaskets on without any issue at all.

I dont remember any problems and I think we left the turbo on the manifold.

Actually unless your motor is super rusty you will be surprised how easy they are to work with. Even though they look rusty, most "heavy on the most" of the time they will come off/on with your fingers once they are broke loose. Good luck

^^ What Sled said.. I've been surprised often at how easy something comes apart, even when it looks like it's gonna crumble or twist in half..

My boost leak tool... http://forum.mopar1973man.com/attachment.php?attachmentid=4284&d=1342802164 From the Galaxy S3