new owner 03 LS vibration

[chessie744]

looking for suggestions just purchased 03 ls 113,000 mi. it has a vibration from 40 to 60 mph its the same if i shift to neutral doesnt really feel like a tire to me i put it on jacks stands put it in gear and looked for a problem any ideas?

 

[regiment1]

I have similar problem on '00. A low vibration from the back end between 40 and 50 mph. The pitch doesn't change with speed, it just fades in at about 40 and out at about 50, and it happens in neutral. It's noticeable when the ambient temps are below 50 degrees, and goes away after a while.

I first noticed it after my half-shafts were replaced, but that may be because the rumble from the old half-shafts was gone and it was now possible to hear this noise.

 

[joegr]

Gen IIs don't tend to have half-shaft problems, but you never know.
The first two troubleshooting steps are:

1. Get a good four-wheel alignment done.
2. Have the wheels/tires road force balanced.

Often, but not always, those two steps will take care of it.

 

[BlackLS06]

Also warped rotors can cause vibration.

 

[joegr]

Also warped rotors can cause vibration.

Usually only when braking, but yes they can.

 

[G-RELL]

Gen IIs don't tend to have half-shaft problems, but you never know.
The first two troubleshooting steps are:

1. Get a good four-wheel alignment done.
2. Have the wheels/tires road force balanced.

Often, but not always, those two steps will take care of it.

+1
Also if the car is new to you.. inspect each rim real well looking for any type of damage. even a small curb check/pot hole can damage the wheel enough to through it off balance.