First, don't kill me cuz I own a Chevy. My boss has an 05 F 350 Lariat dually.We have been working here in central Missouri, well he left and went to Baxter Minnesota for about 3 weeks, was way colder. He kept his truck plugged in over night and left it running most of the day. Since then his turbo has been "barking" very badly. He took it to a dealer and they didn't help much. He's know back in Missouri, took ride with him and it's real bad, only at lower speeds though with hardly any effort it does this.
Anyone expeiencing this, or have any ideas what might be the problem? I told him I would ask around online for him.
Thanks.

Barking? Please elaborate on that sound...

when you accelerate, and let off the pedal too fast, it's like a "woob woob woob" sound. Turbo bark? if I'm not mistaken the sound comes from air actually being lost or "fed" back to the intake.

hmmmmm im completely guessing but isnt that turbo surge? Definately a bad thing. Our Dodge 12v does something similar....:confused:

How about the "warm up valve", aka engine backpressure valve? It restricts exhaust gases to help the motor warm up. I believe it uses air temp and oil temp readings to close the valve.

As far as I know they don't use a warm up valve on the 6.0L's with the VNT. They just increase back pressure with the turbo vanes.

Funny thing is, truck was in shop again this past week, for this. On the summary sheet they gave him, it states:

Customer states whine heard on deceleration from engine advise


Test drove,Verified owners concern. Refer SSM 18155. Vehicles equipped with a 6.0 diesel engine may exhibit a flutter type noise from the air box intake area on deceleration. This noise typically occurs when decelerating after heavy acceleration. The noise is a normal characteristic of the engine and has no impact on engine or turbocharger durability.


This is copied directly. I would scan and post if I knew how.

Its a turbo fart. Totally normal. The 6.0's don't have a wastegate.

First, don't kill me cuz I own a Chevy. My boss has an 05 F 350 Lariat dually.We have been working here in central Missouri, well he left and went to Baxter Minnesota for about 3 weeks, was way colder. He kept his truck plugged in over night and left it running most of the day. Since then his turbo has been "barking" very badly. He took it to a dealer and they didn't help much. He's know back in Missouri, took ride with him and it's real bad, only at lower speeds though with hardly any effort it does this.
Anyone expeiencing this, or have any ideas what might be the problem? I told him I would ask around online for him.
Thanks.
What your hearing is turbo surge or turbo stall, in either case it's not a good thing. I have the older 7.3L and have fixed mine but in the 6.0L is a completely different animal on how to fix the problem.

Surge or stall can destroy a turbo, my 7.3L went through one before I could figure it out(I'm the 2nd owner too), mine was under the 100,000 mile warranty. You might check www.thedieselstop.com (http://www.thedieselstop.com) and see what they have to say on it there beings it's an all FORD forum.

Michael

Like Todd said, The 6L Dosent have a wastegate. It will make 25-30 Lbs stock, If you have your foot into it, and let it off, instead of doing so slowly, it dumps the boost back out of the intake. Known to be normal, ford claims it isnt harmful.

this sound is turbo bark and it isn't a good thing.. as someone states above, it can ruin a turbo pretty quickly. its built up pressure rushing BACK to the turbo after you let off the pedel and this pressure hits the impellars so hard that it stops them and causes that sound. Repeated occurances could easily harm the turbo. Since you Ford guys have no wastegates just like us Duramax guys..this pressure has no where to go except back to the turbo.

sort of like sticking something in a fan to make it stop... won't be doing that too many times.

some of the duramax guys are seeing this too, seems pretty common with turbo diesels.

I'm curious...
Does no one ever use a blow off valve like on a gasoline engine with a turbo or supercharger? This would vent the excess boost pressure off into atmosphere, saving the turbo. Why are they not used on diesels?

I'm curious...
Does no one ever use a blow off valve like on a gasoline engine with a turbo or supercharger? This would vent the excess boost pressure off into atmosphere, saving the turbo. Why are they not used on diesels?
That's called a wastegate. The 6.0 has a VGT and a wastegate is not needed.

Correct me if I'm wrong...
Isn't the wastegate on the exhaust side of the turbo? It allows exhaust gas to "waste" past the turbine to control turbo rpm, thus limiting boost?
A blow off valve would mount between the turbo compressor and the intake manifold. It would allow excess boost to vent when the throttle is shut off.

the turbo on a duramax is also a VVT..variable vein turbo just like the PSD..I think dodge is the only one that isn't.. anyways... there IS a wastegate, but its electronic and controlled in the form of these veins on the turbo. The older duramax's had manual wastegates like you are talking about.

The problem is with the computers/tuners, they haven't quite figured out how to talk and/or tune with the VVT or VGT ones yet. Edge had a big problem with this in the beginning. I had it happen a few times right after purchase but has since never done it.

The frequency of this happening also goes along with exhaust and intake upgrades. more air flowing through trying to exit, etc, etc... mind you this should only happen at WOT.. if you are having this turbo bark just normal driving then take it in to the dealer.

my friend just got a '00, 7.3l powerstroke and we cut the muffler off of it yesterday, and just tied the tail pipe up until he could a piece of pipe put in, when he lets off of it, it sounds like air is being sucked back up the exhaust, is this a turbo bark, we think it sounds pretty cool, we didnt know it was a bad thing i hear it on just about every dodge i hear

my friend just got a '00, 7.3l powerstroke and we cut the muffler off of it yesterday, and just tied the tail pipe up until he could a piece of pipe put in, when he lets off of it, it sounds like air is being sucked back up the exhaust, is this a turbo bark, we think it sounds pretty cool, we didnt know it was a bad thing i hear it on just about every dodge i hear That's not the sound I was describing. It literally sounds like a dog barking"Woob, woob woob" and the sound comes from under the hood.