I've been hearing this noise lately... i thought it was in my head but it seems to be getting worse especially now that the windows are down.

just as the boost starts to come up there is a weird sound only lasting for a second. if i hold the pedal just right it will last longer. i can also get it to do it by holding the brake while stopped.... any ideas? I think it's probably normal but i always have a sharp ear to the engine and honestly have never noticed this before.

it reminds my of the sound i've heard from semi's at part or little throttle driving down the highway but on the bigger trucks it seems to be more of a series of quick "chirps" sounding like a bad bearing. i don't think it's that but that is the best description i can think of. it goes away as the boost comes up. the truck is all stock.....Thanks, Nate

Sounds like normal turbo noise. It starts lower pitched and goes higher pitched? then if you let off the throttle you hear it come back down. Its normal on a turbo diesel engine.

Sounds like normal turbo noise. It starts lower pitched and goes higher pitched? then if you let off the throttle you hear it come back down. Its normal on a turbo diesel engine.


well in searching "noise" threads i noticed it's nearly impossible to relay the correct sound....

I'll give it one more try then drop it, it's a completely different pitch than the turbo, or it would be more correct for me to say the pitch of the turbo dramatically changes for a second or 2.


It almost sounds like a lose belt squealing or screeching or similar in sound to a brake "squealer" that tells you your pads are worn. but as i said just for a split second... if i play with the pedal, i can make it come and go. could this just be the turbo vanes changing pitch, therefore sounding different? any ideas appreciated...

well in searching "noise" threads i noticed it's nearly impossible to relay the correct sound....

I'll give it one more try then drop it, it's a completely different pitch than the turbo, or it would be more correct for me to say the pitch of the turbo dramatically changes for a second or 2.


It almost sounds like a lose belt squealing or screeching or similar in sound to a brake "squealer" that tells you your pads are worn. but as i said just for a split second... if i play with the pedal, i can make it come and go. could this just be the turbo vanes changing pitch, therefore sounding different? any ideas appreciated...

Do you have an air leak in one of the boots or lines that run to the turbo? I don't think the change in the turbo vanes would make a screeching noise, it is a change in the pitch of the exhaust.

sounds like normal turbo noise to me

Check all hose clamps any loss of power or any more smoke then usual. Check your air filter too make sure it is well sitted

Ok,Thanks guys! ... i'll check the above mentioned items.

my lbz started that at 3000 miles. similar to your description.stealer told me i was nuts for awhile. mine was the vane controller out of wack. they installed new turbo to fix my problem. been fine ever since. tech told me that he found oil leaking past a freeze plug on the side of the turbo. said that was a good sign of the vanes being out of "adjustment" (for lack of better term) maybe something to check

Have the dealer check the exhaust. I know it sounds weird but it fixed it for me.

http://www.dieselplace.com/forum/showthread.php?t=233775

my lbz started that at 3000 miles. similar to your description.stealer told me i was nuts for awhile. mine was the vane controller out of wack. they installed new turbo to fix my problem. been fine ever since. tech told me that he found oil leaking past a freeze plug on the side of the turbo. said that was a good sign of the vanes being out of "adjustment" (for lack of better term) maybe something to check


that's bad news! i do have A LOT of oil seeping from everywere on the intake. it is using some oil too.... bummer, i don't plan to have the dealer work on the truck now that is out of warranty. it does seem to be a little down on power and is smoking more than it used to... crap, i thought it was a summer blended fuel making it smoke... i guess at this point i'm hoping i'm nuts and it goes away! :( as soon as it gets a little nicer out around here, i'll have to start working on it.

can anyone describe the sound of the vane's being calibrated on start-up? i was reading on here that it sould change exhaust pitch when it's started [ a sign of the vanes moving] ..... i've listened a bunch of times and don't really here any change.. i'm sure it's more noticable with an open exhaust but can it be heard on a stock truck? thanks everybody! Nate

that's bad news! i do have A LOT of oil seeping from everywere on the intake. it is using some oil too.... bummer, i don't plan to have the dealer work on the truck now that is out of warranty. it does seem to be a little down on power and is smoking more than it used to... crap, i thought it was a summer blended fuel making it smoke... i guess at this point i'm hoping i'm nuts and it goes away! :( as soon as it gets a little nicer out around here, i'll have to start working on it.

can anyone describe the sound of the vane's being calibrated on start-up? i was reading on here that it sould change exhaust pitch when it's started [ a sign of the vanes moving] ..... i've listened a bunch of times and don't really here any change.. i'm sure it's more noticable with an open exhaust but can it be heard on a stock truck? thanks everybody! Nate

I don't hear it on my truck either (stock exhaust) but I do hear it on trucks with a more open exhaust. Starts out with a really deep sound then the vanes adjust and it goes to more of a whistle.

Add me to the list of turbo replacements, Stewietuned on here has my truck right now with an oil leaking turbo.

Cheers,
Eric

It's probably your VVT (variable vane turbo). It's why the LBZs don't take so long to spool up. The vanes open and close. I seem to hear it a lot while braking and going in and out of reverse. You can really hear it with a straight pipe.

The VVT check sounds like the turbo is sucking through the exhaust pipe then goes back to normal. Very noticeable with aftermarket exhaust.

I am not trying to be a smart Axx

how long have you owned it? How many miles driven?

I ask this as it is a variable vane turbo. It is a different noise than say a dodge or ford turbo. If I get a chance, I'll record some audio of mine. I have no cat or muffler so it gets noisey when hammering on it

i have owned it since new ['06] and it has 50K

it's getting worse and worse. it's while driving, part load. i can find just the right amount of pedal/load to make the noise last for several seconds.... sounds like metal to metal screeching....

i also have had 1 quart of oil dissapering every 1K miles....... pretty bummed.

i can now also brake stand the truck slightly and get this noise.

ok, so.... while exelerating........normal turbo whissle comes up... rising in pitch, rising in pitch.... i get to a certain load and the turbo whissle is shadowed by a loud screech that stays at the same tone unless i let off or give 'er more pedal. i know it sucks to try to identify sounds on the internet ..... one day something is going to let go, hope i'm close to home :(

You still have 50k left of warranty on the engine. Take it in.

The noise description sounds like maybe a thrust bearing worn and the compressor wheel hitting the housing? Probably just a leaking boot on the charge air side, but that don't explain the missing oil.

Your Not Crazy, I Have Same Exact Problem! 06 Lbz

you're not hearing the infamous belt squeak are ya?

just read about the 1 quart oil missing - no bueno !

The VVT calibrating sound is noticeable only really with an open aftermarket exhaust. You only really hear it in the exhaust note as it deepens then goes back to normal sounding. I can hear the vanes opening and closing faintly when it happens. Yours though sounds like a bad turbo.
Turbo covered under 100k engine warranty, take it in.

the last couple days i did the blocker plate, pcv reroute and put a 4" exhaust and capped the resonator. now the thing makes so much noise i can barely hear the momentary "screech" [for lack of better description].... i have 0% trust in the dealer... going to ride it out a little longer, suppose i'm hosed now i did a few mods..?..

the last couple days i did the blocker plate, pcv reroute and put a 4" exhaust and capped the resonator. now the thing makes so much noise i can barely hear the momentary "screech" [for lack of better description].... i have 0% trust in the dealer... going to ride it out a little longer, suppose i'm hosed now i did a few mods..?..

Unless the dealer can directly link your problem to your mods they still have to honor the warranty...

If I were you I wouldn't have done those mods at this point. :rolleyes:

is it at around 1000 to 1200rpms when you play with the throttle? I have a screech type noise too with no loss of power, no more smoke than usual, and no oil use. it sounds like a vibration of some sort right when the engine hits a certain rpm. somethings rubbin somewhere

Add me to the"screech type noise" list.
Can't seem to find it (Yet)

I had a boost tube clamp on drivers side that was not tight all the way and had a wierd high pitch sound at around 1200-1600 rpms for just a split sec, tighted it and it went away. Also check to make sure the cap that u place for the resonator plug is tight also. Oil in these boost tubes/intercooler makes those rubber tubes always having to be tighened, even for awhile after pcv reroute.

One more thing about the blue rubber tubes. Someone said to clean the tube on the inside real good, let dry, then spray some hair spray on intercooler pipe outlet and inside blue rubber boot, let dry, then tighen it down and it will not slip of as easy. I did this on mine and have had no more problems with leaking. I do keep a ckeck on the blue tube clamp though!

07 classic lbz and never heard the noise until i took the kitty off and straight piped it. i to now get that wrapping noise when i let off the fuel i have 15k on it egr blocker plate finger stick and juice with attitude had 4 in exhaust with muffler and just straight piped it and took the cat off last week , note CARB has just said that the will be implementing the smog checks starting in 2010 on diesels so keep those kittys handy. i am a smog tech and have had licsense for 18 years now and this will happen we just dont know the extent of it yet.

07 classic lbz and never heard the noise until i took the kitty off and straight piped it. i to now get that wrapping noise when i let off the fuel i have 15k on it egr blocker plate finger stick and juice with attitude had 4 in exhaust with muffler and just straight piped it and took the cat off last week , note CARB has just said that the will be implementing the smog checks starting in 2010 on diesels so keep those kittys handy. i am a smog tech and have had licsense for 18 years now and this will happen we just dont know the extent of it yet.
Did the noise start after you installed the EGR Blocker plate? If it's not installed all the way down, it won't seal and you will hear that noise when you let off the fuel. Same thing happened to me. I had to file the leading edge of by blocker plate to get it all the way down.

is it at around 1000 to 1200rpms when you play with the throttle? I have a screech type noise too with no loss of power, no more smoke than usual, and no oil use. it sounds like a vibration of some sort right when the engine hits a certain rpm. somethings rubbin somewhere
yea, i did have the exhaust hanger on the trans make a rattle... but yea, the screech.... man, there is no mistaking that! like i said now that i have done some mods, it's not as noticable. it is BOOST related not nec. rpm related. when shes good and hot like after pulling a trailer... it is more pronounced.... idk :(

i will check the clamps and resonator plug... matter a fact, i'll go do it right now ;)

yeah i figured that we werent hearing the same noise. i have the rattle

i have owned it since new ['06] and it has 50K

it's getting worse and worse. it's while driving, part load. i can find just the right amount of pedal/load to make the noise last for several seconds.... sounds like metal to metal screeching....

i can now also brake stand the truck slightly and get this noise.

ok, so.... while exelerating........normal turbo whissle comes up... rising in pitch, rising in pitch.... i get to a certain load and the turbo whissle is shadowed by a loud screech that stays at the same tone unless i let off or give 'er more pedal. i know it sucks to try to identify sounds on the internet ..... one day something is going to let go, hope i'm close to home :(

You can add me to the list of the problem as well. This discription is right on with what i am hearing. I have no oil loss though. Have you found anything out yet about what is causing it?

You can add me to the list of the problem as well. This discription is right on with what i am hearing. I have no oil loss though. Have you found anything out yet about what is causing it?
no, no news from me anyway.. i can still hear it but like i said with no cat ect. ..... it's very hard to hear it. i have kinda just let it be. it did start very faint and progressivly get longer/lounder with more miles [ 55k now, started at 40kish].... heck idk? i'm just runnin it..?..

My truck went in to the dealer today for the problem, it was getting worse rather quicky and since its under warranty I would like to have it fixed. They called me today and said they were able to duplicate the sound and told me my power steering lines were leaking which made the pump low on fluid and that was causing the sound. I am glad they fixed the leaking power steering lines but i know that was not the noise or the issue. I was able to have a friend get in the truck and make the noise happen and i was under the hood just listening around and the noise was coming from the back of the motor right where the turbo is. I guess I will see when I go pick it up tomorrow after work, but my gut tells me they didnt fix it.

So did you get anywhere with this whine/whistle? I am having a similar issue with my LLY

I didn't get anywhere with the dealer, I kept making an appointment for it, showing up and bothering them about it. I work only 1/2 mile away from them which makes it easy. I got the truck to make the noise once good and loud and the face the service writer made was complete shock as if to say I dont know what that is but kept making up what he thought it was. I got excuses of its the fan belt, its the shrouds around the turbo, its normal dont worry, its the band clamp on the downpipe. They went through and changed the belt, still did it, cleaned the exhaust downpipe mating surface and new clamp, still did it. Thats when i got the its normal dont worry speach. I kept getting a run around about it and the last time they basically threw in my face because they can't get it to produce the sound its not broke so there for they cannot fix it even though I was able to get the sound once good and loud and a couple other times faintly.

I have not heard it for a while lately, knock on wood.... I have since then straight piped the stock exhaust, gutted the air box and capped off the resonator. I capped the resonator first and I remember hearing it still after that but then after straight piping the stock exhaust I dont recall hearing it again. I know its not because the exhaust is too loud because its still quiet in the truck.

So as of right now I dont know what to tell you on what the true cause of the noise is, I wish i knew. I have put 13,000 miles on it with the noise and no problems, but it still bugs me deep down.

If you would not mind watching these videos, I would appreciate it. See if this sound compares to the one you were hearing. Mine started doing it a couple weeks ago and has been steady. I dont mind the sound so much, just worried that my turbo is about to bite the big one.

http://www.youtube.com/watch?v=PsUPvZhhwlY

http://www.youtube.com/watch?v=T7Qlpod27Bw

Thats way different from what I was hearing. Mine was right at 1300 rpm I would get what I now call a buzzing sound. Yours is more of like a whinning sound ontop of the normal turbo whistle.

Yea I am at a loss......gonna put it back to stock and take it in...see what they say

Check all hose clamps any loss of power or any more smoke then usual. Check your air filter too make sure it is well sitted

i'd check the clamps & hoses verry well ! ! if all else fails. get the biggest strongest chain you canfind, chain the rear hitch of the truck to the strongest heaviest thing you can find - like an old oak tree, old bulldozer, mother-in-law :D!! either put the truck into reverse and push against the heavy object or pull forward take the slack out of the chain - and have someone else power brake the engine untill you hear the noise, and maybee look around the engine area to see if you can find an air leak BUT BE VERRY VERRY CAREFUL ...#1 the truck dosent run you over...duhh!! #2 DO NOT NOT NOT NOT run your hand over the intake tubes - while the truck is boosting up- lookin for a leak, compressed air can puncture your skin and KILL you!!! THIS IS NOT A JOKE!!! is it a serious medical fact!!!!!! if you get air in your blood its basically like running a fluid pump dry, it cavitates and self destructs!! i do not know what psi will puncture your skin its proably higher than 80 psi but i feel the need to tell you this anyway. yes its true that the stock boost tops out at around 20-25 psi, but that is constantly comming out of the turbo, not like a small puff it gonna be a sharp leak! so i guess what im saying is use a piece of paper around the tubing to look of pin hole leaks, if i suspect a certain hose, shut the truck off, remove the hose and inspect it THROUGHLY!!!! but i cant see the noise going away usually it will stay constant, get worse with increased boost- or go away alltogeather, but weirder things have happened! check the tubes on the turbo- the video clip sounds like a hole on the outlet of the turbo?? good luck- this kind of stuff bothers me too!!!

Thanks for the replies. I have been through every thread I can find on here. I see probably 10 or more people say that have experienced this same problem but the thread dies and no one ever says if they got it fixed or if they went and traded it in on a Dodge LOL. Ill go over the truck again tomorrow. I had my dad come down and with the truck in 4wd and e-brake on he got it into boost and I can hear it in the turbo. Its in the area between the compressor and exhaust housing. I also used soapy water in a bottle and sprayed it on everything in that area looking for a leak and found nothing. I am really lost on this. Going to check all of the exhaust from manifolds to turbo over tomorrow.

if your trying to get the truck to boost up without moving- leave it in high range, putting the truck in 4 low makes it easier for the truck to move (through the lower gearing) with low rpm... when i put my truck in 4 low i have to STAND on the brake to stop the damn thing from moving!!! talk about POWER!!! :) the truck will still jump if it is boosted up in 4 low! --- anyways back to the subject at hand - do u have a boost gauge on your truck? if so what does it do when the noise is occouring? if not....it might not be a bad idea to atleast hillbilly one in for diagnostic purposes! manual gauge would be much better than a digital too! ( atleat for me ) i like to see what the needle is doing. fluttering- studdering- ect? just a thought ...... good luck!

No gauge but I might pick one up. Just dont want to buy parts till I find the right one.....After market turbos dont look like an option...3k + :eek:

Update on this....looks like the bearing is toast in the turbo....has a lot of play in it when I move the compressor wheel around.

i'd be careful about jumping to conclusions, all turbos have play in the shaft, because - the turbo shaft rides on a film of oil when the oil pressure is up to operating range. the only kind of turbo that dosent have play in the shaft is the high performance turbos with ball bearings on the turbo shaft. - to be perfectly honest i dont know if the lbz has ball bearings on its shaft? im inclined to think it dosent -since its more expensive to produce-. but if it is really wobbling around like a limp banana.... then i'd say you found your problem! another way to double check you results, is to remove the snail looking part of the compressor -or- the exhaust side of the turbo, again- ive never done this on an lbz turbo but, EVERY turbo ive ever seen you can remove both sides and basically just replace the center section (which includes the cartridge and both compressor and exhaust wheels, and the shaft assembled and ready to go) -- anyways remove the snail and look the the inside and look for evidence of the turbo fins rubbing the housing - or broken fins! if you see this - then yes your turbo is shot!! i hate to be a broken record but, if i was you i'd still try to get a base reading on what the boost is before you go any further.....

Turned out to be a bad gasket between the EGR housing and intake where the exhaust and intake air are mixed before they go into the intake.

my lbz started that at 3000 miles. similar to your description.stealer told me i was nuts for awhile. mine was the vane controller out of wack. they installed new turbo to fix my problem. been fine ever since. tech told me that he found oil leaking past a freeze plug on the side of the turbo. said that was a good sign of the vanes being out of "adjustment" (for lack of better term) maybe something to checkX2