aris_unlimited

I have an 07 tahoe and I have been having some problems with it shuddering. I have never experienced something like this before so if someone could help me out that would be great.

Symptoms: When at idle and in gear the car tends to shudder, but not very much at all. And it is always intermittently, it will shudder wait a few seconds than shudder again. This always seems to be the case.

When at highway speeds 65-75mph and I am just maintaining speed, not slowing down or speeding up the shudder happens just as often as it does while at idle but it is much more violent. It feels like I keep hitting a really bad bump every couple of seconds. The car seems fine when accelerating or decelerating, but when I am trying to maintain speed or at idle is when I notice it.

Any ideas?

I have already had the wheels balanced and changed the spark plugs (old ones looked ok, but changed them anyways).

aris_unlimited

Just noticed that I accidentally put this in the pickup section, could a mod move it to the tahoe section for me

Chevrolet Customer Service

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Is the shudder in the steering wheel? If so, it could be caused by an unstable fluid flow in the power steering assembly. This is just a suggestion, not a diagnosis.

I encourage you to take the vehicle in to be inspected by a certified technician. They will be able to offer additional information after a physical inspection.

Louis
GM Customer Service

aris_unlimited

No the steering wheel doesn't have the shudder. It's barely noticeable at idle, but at highway speeds is when you really start to feel it. Feels like I am hitting a really big bump or pot hole. It makes the whole car shake, but the steering doesn't really seem effected.

Chevrolet Customer Service

<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:PunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> </w:WordDocument> </xml><![endif]--><!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" LatentStyleCount="156"> </w:LatentStyles> </xml><![endif]--><!--[if gte mso 10]> <style> /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} </style> <![endif]--> Possibly the wheel bearings? It is difficult to diagnose an issue like this over the internet. I suggest taking the vehicle in to be inspected by a certified technician.

Louis
GM Customer Service

aris_unlimited

I've already dropped it at the dealer, I am just trying to figure out what the cause could be (dealer has had it 3 days now).

So far possibly solutions include:
Wheel balancing (already had done)
Spark plugs (replaced those, they are fine)
clogged injector or other fuel system problem
wheel bearings
cv axles
alignment (doesn't pull in any direction, figure it's ok)
torque convertor
transmission
rack and pinion

A couple of these solutions are assuming that the very minor shudder at idle is just normal engine feel.

cleveland63b

if it happens at idle it shouldn't have anything to do with any suspension or drivetrain components....does the RPM gauge fluctuate at all or surge?

aris_unlimited

No the rpm gauge stays steady at idle, more of just a feel. But it could be just normal engine feel. I haven't had it long enough to know, and the whole time I've had it, it has had this problem. So kind of impossible for me to differentiate between the two.

aris_unlimited

Drove my dads silverado yesterday (same motor) and it seems to feel the same at idle so my guess is it is normal engine vibration, and I just looked at it because of what we felt at hwy speeds.

Dealership has decided that the tires are to blame. They were wearing funny and had a bad alignment (also possible broken belts in tires). Putting on some tires they had laying around the shudder went away. So now just deciding what kind of tires we are going to put on it.