2005 LLY w/ loud grouning noise on accelaration

[durachev]

I have a 2005 LLY that when ever it gets heated up and/or you have been towing with it, it makes a really loud grouning noise coming from the turbo (or so my dealer tells me). It only does it on accelaration or decelaration below 2000 rpm, and especially if turning too. The sound is similar to the sound a bad steering pump makes, but my dealer tells me it's from the turbo and GM can't find a fix it yet.

Does anybody else experience this and do you have any additional information on the cause? For a 50k truck it's really annoying and embarrasing.

[ccole]

Hey there.... Ironic you should bring this up. My 2005 with 6000 miles has done this a few times when warmed up. I thought it sounded like a power steering pump groaning. It has happened a couple times and it was really noticable while turning.

[Jim Brzozowski]

What will your dealer tell you if you tell him no way can turning the stearing wheel cause a change in the sound of the turbo. If the bearings in the turbo are so lousy that it would shift its position just because you make a turn, the thing would fly apart the first time you stood on the go pedal. I'd suspect the stearing gear or power stearing pump.

[William Lee Gingerich]

My 05 duramax does the same thing especially in tow haul on the last downshift it really groans. It especially does it when I've been towing for a while in hot weather.

[William Lee Gingerich]

Hey durachev I just got a recall notice on my 05. It says {05006 Hydro- Boost Accumulator Over- Pressurization} I think this sounds like the fix to our problem.

[durachev]

I haven't got anything yet in the mail, can you scan it or fax me a copy of it???

[William Lee Gingerich]

I dont have it with me right now as im on the road. I will see what I can do when I get home. Also I talked to my service manager and he said that the recall has to do with a seal in the brake booster that can fail and then no brakes, so maybe this is not a fix to the problem. I am taking it in soon and having it looked at and will post as to what they found out.

[LJ]

Mine is doing the same thing- exactly as you guys describe- sounds awful- like it's a groaning elephant in terrible pain. It's much worse when turning. I was sure it was the power steering, but got talked out of that theory. Now it's back. Please do post what you find out.

[durachev]

So far I have got nothing, dealer says still workin on it. It's been a year and it's really getting old. I have a friend with an 05' also and it doesn't do it.

[durachev]

I just talked to my dealer today, and they apparently have come out with a bulletin. Some sort of exhaust collector that they are going to replace. They ordered the part without seeing the truck and it should be in later this week. I will post more info on the bulletin #, etc. after it's fixed and I get a chance to road test it. With any luck I will get it fixed before I hit the road again this weekend.

[William Lee Gingerich]

Sounds interesting.Keep us posted.

[William Lee Gingerich]

Forgot to mention this. Took my 05 truck in for this same noise and they could not figure it out either.They thought it had something to do with the abs system but no solution.

[durachev]

I got my new exhaust and converter installed this week, I haven't had a chance to tow anything yet to see if the noise returns but it does seem to sound a little more like our 04' LLY. Can't quite describe it, but it does sound a little different than before. The service guy at the dealer has a buddy having the same problem so I am the guinea pig to see if it fixes the issue. I probably won't get a chance to tow anything soon, boating season is over for me and that's the majority of my towing.

[Hunnington]

Could it be the Clutch Fan. My LLy has made a similar sound when it has been hot out and pulling.

[durachev]

Nope, that's not it, this noise is completely diff. from the clutch fan. Since the new exhaust my mileage has jumped 1-1.5mpg.

[dmaxmule]

durachev
what ehaust did you purchase,how much,and where?

[durachev]

It's factory, they had some sort of bulletin on it.

[durachev]

Well I took my first trip towing this last weekend. It seems to be only slightly better if at all. The noise still comes back after towing or driving a long distance.

It still sounds like something with the power steering pump. I will have to get it back in within the next few weeks.