Propeller Shaft - Vibration at Highway Speed

File In Section: 4 - Drive Axle

Bulletin No.: 67-41-01

Date: March, 1996

Subject:
Vibration at Highway Speed (Replace Propeller Shaft)

Models:
1993-96 Chevrolet Camaro
1993-96 Pontiac Firebird
with 5.7L V8 Engine (VIN P - RPO LT1)

Condition

Some owners may experience a vehicle vibration at highway speeds. When measured at the driver's seat track, this vibration will be a 1st order driveline frequency. The same vibration can be confirmed at the axle pinion nose and at the rear extension housing of the transmission.

Important:
When measuring vibration frequency on a hoist, the rear of the vehicle must be supported by the axle tubes in order to maintain the proper vehicle trim height. This will prevent vibration due to excessive driveline angle. Also, any vibration due to excessive driveline angle will appear as 2nd order driveline frequency vibration.

Cause

First order driveline vibration may be caused by beaming between the engine and transmission.

Correction

A previously released propeller shaft is available to address the highway speed vibration condition. This reduced mass propeller shaft is constructed of aluminum less a pinion damper.

Verify condition per above note that the vibration is 1st order driveline disturbance; preferably using an Electronic Vibration Analyzer (EVA).

Other conditions such as excessive driveline angle difference may produce 2nd order driveline vibration concerns. The proper procedures to measure and correct for excessive driveline angle condition are not shown in the current Service Manual. Consult a 1992 Service Manual for the proper procedure. The front and rear propeller shaft angle must be less than one (1°) degree of each other.

Important:
Due to the removed damper, the alternate propeller shaft may unmask existing rear axle noise. A lighter propeller shaft will reduce vibration but will possibly unmask axle noise, while a heavier propeller shaft will mask axle noise but may cause vibration. This inherent condition is always the trade-off. It is suggested that the vehicle be test driven to evaluate axle noise before and after parts are installed.

Install alternate propeller shaft,
Part Number 10085375.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation Labor Time

F1280 Use published labor operation time.