High pitched squeal at 30 psi

[vloney]

I think I've got one like alex had, High pitched squeal at 30 psi boost (only under moderate load). Can't get it to do it in the bay, have to hook up 2 trailers to hear it (gooseneck, and bumper hitch). Just doing preliminary checks now.

[Alex Bruene]

I was able to find my leak by finding the soot on the flex pipe on the right turbo inlet pipe.

[DwayneGorniak]

I have a two foot piece of 1/4" brake line that is bent 45 degree at the last two inches of the pipe. I put that pipe inside of the rubber hose on my stethoscope and run down along the pipes. I always find leaks with this tool.

 

Warning: this can really hurt your ears if you get it too close to the exhaust leak or if the pitch is really high.

[vloney]

It reminds me of a blower motor squeal.

[vloney]

Update: It turned out to be the thin gasket between the turbo, and downpipe. When I loosened the downpipe, it jumped up 2". The gasket showed soot trails. The expansion joints were all ok. After replacing the gasket, and making sure the exhaust was unloaded. Tried it with both trailers (no noise), would also build much more boost. Customer said this was the first heavy pull since purchasing (4000 miles).

[mchan68]

Do you mean TSB 07-07-07, for 1.0HR.?

[vloney]

Thats pretty much the same thing, but there was no complaint of smoke, just the squeal noise. And the only time it would do it, is when he had 2 trailers on, and on a steep hill. The noise would be for 2 seconds or so. Even after the repair was done, we couldn't verify the repair until he hooked up both trailers.