V6 vibrations at low rpm's (30-40 mph)

[ZX14]

Did GM ever come up with a fix for this issue?

[ibmrs]

Mine does it too. I have written it off as exhaust drone/resonance (stock). it is more of a low rumble from the rear of car, not a wheel vibration, as it is a sound vibration i think, not a chassis vibration. Almost as if too much bass on a blown speaker, but does it without radio on too. Change rpm up/down and vibration goes away. it is annoying. 2200mi on mine. i always figure i was going to change the exhaust so haven't worried too much. I notice it most at the 35-45 mph with light acceleration or just maintaining speed. Back off or accelerate and it stops immediately. So definitely not tires, because they would do it always at that speed.
I am going to throw out those big trash cans on the back of the car that GM calls mufflers anyway, so i haven't done much about it.

[camaro_RS]

I didn't see this thread until after I went to the dealer today for this exact problem.

I noticed mine from the sound way more than from a vibration, though. Not many of you are mentioning a sound...only the vibration. I think my car sounds like crap in the 1000-2000rpm range when slightly pressing on the gas pedal. It is a shuddering sound you definitely don't want to hear from a new car. When I press harder on the pedal it's not there and when I completely let up it's not there.

So.....at the dealer. I drove it around the parking lot with a mechanic to replicate the sound. He heard it and said "we'll see what we can do to fix it". I waited about 30 minutes or so. Manager came back with a GM "Bulletin" and said it concerned the fuel pump and injectors. The Bulletin he gave me is #07-06-04-025F. It is two pages. He told me it is normal and that there is nothing for them to do.

I just said......"Oh, okay. I'll go look it up". I was kind of stunned that my car had to sound like this and I didn't really know what to say.

When they called me to the cashier's desk to get my keys the lady asked me; "So, how do you like your Camaro?" I said "I liked it a lot until now"..."it sounds like a diesel!" She said, "Oh, that's a good sound." I said "No, this isn't the "good" sound". Anyway, I wasn't rude, just dumbfounded.

I drove home livid ....and now I find this thread. At least now I know my car isn't the only one doing this (or something similar).

Now we just need to find something to do about it.

[Teodog]

+1. Been to dealer twice to document issue. Vibration when driving at 1100-1200 RPM, worse in higher gears. Waiting to see if GM will address this based on multiple owner-to-dealer complaints.

[Dennyd]

Come on you GM Service Guys monitoring this issue. I'm sure your engineers can identify, isolate and fix this problem. It's too bad when you have to pay $30K for a car with such a rough sounding engine. In an attempt to isolate the problem with my car I have been able to even get the engine rpm to pulsate with the resonance. Carefully holding at 1200 rpm and just rolling into the accelerator I was able to get at least a 50 rpm pulsation. My car exhiblts both an audiable rersonance and a chasis buz that you can hear and feel in the accelerator pedal, the floor pan ,and the gear shift lever.

[TooCool5]

Originally Posted by Dennyd

Guys,
My 2010 V6 Auto does the same thing. It occurs at 1200rpm and it doesn't matter what gear you are in it only gets worse as the gearing goes up. If you are carefull you can sense it even when in park if you bring the r's up to 1200. It is deffinitley a 20 hertz harmonic and it may come from exhaust or drive train mount isolation. I know it drives me carzy and I don't wan to be paddle shifting it away all of the time.

I can assure you, my 2010 does not do this.
Minor thump at 1200 rpm at cold start up only. Smooths out when idle comes down and it warms up.

[julio820]

And where the he'll is Jeff??!Jeff from GM is all talk and no action. +1 same issue here I'm nit gonna explain it bc 50 people already did so I guess we can't do anything about it and just wait for a fix...

[Chevrolet Customer Svc]

I'm sorry you think I'm not trying to find solutions for this but I assure I exhaust all my resources before I throw in the towel and I can assure you I haven't done that yet. I'm still looking for responses from our other departments and looking to see what I can get from our Technical team on this. So far I haven't been able to make much progress but, when I have something to update you all with I will.

Jeff Morris, Chevrolet Customer Service

[rydahog]

why would you be in 6th at 45 mph or so...car is lugging in and weird things appear worse..get in 3rd gear..

[Dennyd]

It's not just an engine lug problem. It is a 1200 rpm problem. It occurs at 1200 rpm no matter what gear you are in. It will even do it in neutral at 1200 rpm.

[Dennyd]

Just figured I would update my 1200 rpm problem. I now have 8000 mles on the car and the problem has gradually grown worse. It now excites something in the door panel and now I have door panel vibrations. When new the car did not have this problem. It first occured at about 3000 miles and has progressivly grown worse.
This weekend while driving my wife's Monte SS with a 3800 V6 auto I noticed that the engine rpm never drops below 1500 rpm. For our cars it seems to me, a simple interim fix would be to revise the software to change the tranmission shift points to not let the engine rpms drop below 1500. Apparantly this engine doesn't like to operate smoothly at 1200 rpm.
All I know for sure is that it is becoming so annoying that I am now considering seLling the car, but anyone test driving the car will notice the 1200 rpm buz and ask what it is? and all I can respond is UNKNOWN.

[Shu71]

I asked this a while back, maybe page one or two of this thread, but does anyone with headers and or a tune still have this issue? I have the M6 transmission and I do not get the 1200 rpm vibration, but mine comes in at 2200 rpms and steady speeds light throttle position. I can shift around it.

[irocnroll]

Originally Posted by rydahog

why would you be in 6th at 45 mph or so...car is lugging in and weird things appear worse..get in 3rd gear..

Because thats when the computer shifts it into 6th gear. We have no control over that unless you constantly switch the car into sports mode.

[ZX14]

Don't worry about it, Jeff is working on it as we speak.