Trailblazer Vibration

[Johnwide53]

I have a 2003 Trailblazer with less than 5 thousand miles on it at this time. I have this vibration that comes at about 58mph and stays till about 65mph. My local dealership has had the vehicle 4 times and is now coming to a conclusion that this is a natural vibration and there is nothing that can be done. I find this answer unacceptable, ive called cutomer service and im getting no where fast. Is anyone else experiencing this type of situation.

[Cool Zr2]

I'd say a drive line problem, like driveshafts, unbalanced tires or rims themselves.

[Wxman]

You aren't clear what kind of vibration. I had a slight vibration in the steering wheel at about the speeds you mention. Dealer did get it fixed. The tires were in balance, but the ticket said the "road force test" was out of GM specs on one wheel. The tech said he was able to get it in specs by rotating the tire on the wheel. The vibration disappeared. I am not sure if all dealers have the equipment to check the road force. It has something to do with a mounting problem or sidewall imperfection that creates a different amount of sidewall flex (force) at different points of the revolution, which creates a virbration.

 

Just a thought

Good luck

Wxman

[Wingnut]

You aren't clear what kind of vibration. I had a slight vibration in the steering wheel at about the speeds you mention. Dealer did get it fixed. The tires were in balance, but the ticket said the "road force test" was out of GM specs on one wheel. The tech said he was able to get it in specs by rotating the tire on the wheel. The vibration disappeared. I am not sure if all dealers have the equipment to check the road force. It has something to do with a mounting problem or sidewall imperfection that creates a different amount of sidewall flex (force) at different points of the revolution, which creates a virbration.

 

Just a thought

Good luck

Wxman

Wow, I have never even heard of that one

 

 

I doubt that the tires would cause a vibration at set speeds....Based on my experience (Not an expert), tire balance issues are cumulative, that is, they get worse as speed increases. Not go away once you reach a certain speed.

 

Now U-joints on the other hand...I have had those that vibrate at very specific speeds, then go away as you increase, or decrease speed.

[N4gkj]

this might apply to your situation....

 

 

Bulletin No.: 02-03-09-002A

 

Date: September, 2002

 

TECHNICAL

 

Subject:

Intermittent Boom, Rumbling Noise and/or Disturbance Heard in Passenger Compartment While Driving at Highway Speeds (Replace Rear Coil Springs)

 

Models:

2002-2003 Chevrolet TrailBlazer

2002-2003 GMC Envoy with Rear Coil Springs

 

(Refer to Parts Information table below for applicable RPO Code usage)

 

This bulletin is being revised to add the 2003 model year. Please discard Corporate Bulletin Number 02-03-09-002 (Section 03 - Suspension).

 

Condition

 

Some customers may comment on an intermittent booming, rumbling noise and/or disturbance heard in the passenger compartment while driving the vehicle at highway speeds. This condition occurs while driving at steady speeds between 1550-1700 engine RPM in 4th gear (NOT during acceleration). This equates to 64-80 km/h (48-50 mph) for vehicles with a 4.10 axle ratio (RPO GT5), 83-86 km/h (52-54 mph) with a 3.73 axle ratio (RPO GT4) and 93-96 km/h (58-60 mph) with a 3.42 axle ratio (RPO GU6).

 

Cause

 

The noise/disturbance occurs when the torque converter momentarily goes to a full lock-up state, resulting in zero slip of the torque converter. When the torque converter returns to normal ECCC mode with 30 RPM of slip, the noise will go away. The disturbance generated by the zero slip condition is amplified and transferred into the passenger compartment by the rear coil springs.

 

Correction

 

Replace the rear coil springs using the following service procedure.

 

Notice: Use care when handling the coil springs in order to avoid chipping or scratching the coating. Damage to the coating will result in premature failure of the coil springs.

 

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information in the Service Manual (SI Document ID # 744862).

 

2. Support the front frame rail of the vehicle with a suitable adjustable jack stand.

 

3. Support the rear axle with a suitable adjustable jackstand.

 

4. Remove the two shock absorber lower mounting bolts.

 

5. Lower the rear axle enough to remove the tension on the rear coil springs.

 

6. Remove the rear coil springs.

 

Important: ^ It is critical that the correct coil springs are installed in the correct location.

 

^ The LH and RH springs are not necessarily the same part numbers.

 

^ Each vehicle may have a different build combination.

 

^ Use the RPO label located in the glove box to determine what part number springs to replace.

 

^ Only small quantity of parts are available. Please DO NOT order for stock only.

 

7. Select the correct new rear coil spring part numbers. Refer to the Parts Information below.

 

8. Install the upper bushing seats on the new rear coil springs and install the springs into the vehicle.

 

9. Raise the rear axle with the adjustable jack stand.

 

10. Install the two shock absorber lower mounting bolts.

 

Tighten

 

Tighten the two shock absorber lower mounting bolts to 80 N.m (59 lb ft).

 

11. Remove both of the adjustable jack stands from under the vehicle.

 

12. Lower the vehicle.

[Envoy Fan]

You aren't clear what kind of vibration.  I had a slight vibration in the steering wheel at about the speeds you mention.  Dealer did get it fixed.  The tires were in balance, but the ticket said the "road force test" was out of GM specs on one wheel.  The tech said he was able to get it in specs by rotating the tire on the wheel.  The vibration disappeared.  I am not sure if all dealers have the equipment to check the road force.  It has something to do with a mounting problem or sidewall imperfection that creates a different amount of sidewall flex (force) at different points of the revolution, which creates a virbration.

 

Just a thought

Good luck

Wxman

Wow, I have never even heard of that one

 

 

I doubt that the tires would cause a vibration at set speeds....Based on my experience (Not an expert), tire balance issues are cumulative, that is, they get worse as speed increases. Not go away once you reach a certain speed.

 

Now U-joints on the other hand...I have had those that vibrate at very specific speeds, then go away as you increase, or decrease speed.

Look at www.hunter.com The Hunter GSP 9700 will check for road force balance. Not all dealers have them. Even the ones that do sometimes have a technician that doesn' t fully understand how to use the balancer.

 

As was also mentioned, the drive shaft could be out of balance. This has been discussed on other forums.

 

My suggestion is to not let the dealer "kiss you off". This is not a normal problem. It should be resolved.