turbo sucking sound really loud in Overdrive

[BIGGER]

2002 F350 7.3L 4x4 6spd
5" lift with 35" tires
BHAF, 4" MBRP Exhaust, 10K Mod, boost and EGT gauges.

This is the first load I pulled since doing the 10K Mod and BHAF.

Coming from NM with the Blazer on a bumper pull trailer (maybe 7000lbs). Truck pulls and runs great.

When I am on a long uphill grade and I downshift to 4th, run the RPMs to about 2400 and shift into OD, the sucking sound from the turbo gets really loud. It gets loud enough to drown out any conversation or music. At the same RPMs in 4th the noise is about half as loud. Doesn't necessarily sound mechanically bad, but IS obnoxiously loud.

Is this normal? Anything to worry about?

I did over boost a few times, but the boost gauge didn't jump around like I was expecting. On one big hill, I hit 23psi in OD. On a few hills I did also get a little surge, but I backed it off a little to prevent that.

Thanks in advance.

[NCHornet]

Sounds like it could be a boost leak. Do you have gauges? You should!! Check your boots and up pipes for leaks and/or loose connection.

NCH

[BIGGER]

I do have gauges.

I can push the boost to 23psi on OD. I am not certain, but I don't think I could do that with a leak. The boost gauge holds steady also.

I checked the boots and everything LOOKS ok, haven't pulled them off and looked real good.

[BIGGER]

any more ideas?

[groomzybanshee]

the same thing happen to me abouta week ago my intercooler pipe was loose.