Driveshaft Runout and Balancing

WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

With the vehicle in NEUTRAL, position on a hoist. For additional information, refer to JACKING & LIFTING .
Remove the bolts retaining the heat shield to the vehicle.

Fig 1: Identifying Bolts Retaining Heat Shield To Vehicle
Courtesy of FORD MOTOR CO.

WARNING: Personal injury can result if the heat shield contacts the driveshaft during the balancing procedure. Secure the heat shield away from the driveshaft.

Fig 2: Securing Heat Shield Away From Driveshaft

Courtesy of FORD MOTOR CO.

Move the heat shield forward and secure it with a wire.
Remove the rear wheel and tire assemblies. For additional information, refer to WHEELS & TIRES .

WARNING: Reinstall and tighten the wheel nuts to prevent them from coming loose during the balancing procedure and causing personal injury.

Install and tighten the wheel nuts. For additional information, refer to WHEELS & TIRES .
Open the hood to provide additional cooling.
Turn off the traction control, if so equipped.
Have an assistant get in the driver seat.

CAUTION: Do not exceed 70 mph.

Have the assistant accelerate to the speed where the imbalance is most noticeable.

WARNING: Keep hands, hair, head and clothing clear of rotating parts and hot exhaust components.

NOTE: The marker will contact the heavy side of the rotating driveshaft.

Fig 3: Inserting Marker Into Piece Of Plastic Pipe

Courtesy of FORD MOTOR CO.

Insert a suitable marker into a 305-mm (12-inch) long piece of plastic pipe. Using the heat shield lip as a brace, slowly move the scribe towards the driveshaft, in an area clear of the balance weld weights, until it lightly contacts and marks the driveshaft.
Have the assistant stop accelerating and shut off the engine.
With the driveshaft stationary, observe the mark on the driveshaft. A partial mark (less than 360 degrees) indicates the presence of an imbalance. A 360-degree mark indicates that there is no imbalance or that the pressure applied to the marker was too great. Proceed as follows if the mark indicates an imbalance. Otherwise, reinstall all components.

Locate the bolt in the flex coupling opposite the mark. Install a 1.23-gram (red) weighted nut onto this bolt. This is the light side of the driveshaft. Refer to the following chart for balance nut weight and color code information.

BALANCE NUTS

Kit Part Number	Color	Weight (grams)
XW4Z-4613-AA	Red	1.23
	Silver	2.75
	Green	5.6
	Black	4.0

Fig 4: Locating Flex Coupling Bolts

Courtesy of FORD MOTOR CO.

WARNING: Keep hands, hair, head and clothing clear of rotating parts and hot exhaust components.

Fig 5: Inserting Marker Into Piece Of Plastic Pipe

Courtesy of FORD MOTOR CO.

Repeat the marking procedure.
Have the assistant stop accelerating and shut off the engine.
With the driveshaft stationary, observe the mark on the driveshaft. If the new mark is 360 degrees, reinstall all components and road test the vehicle. If the vibration is still present, remove the 1.23-gram (red) weighted nut, install a 2.75-gram (silver) weighted nut in its place, and proceed as follows.

WARNING: Keep hands, hair, head and clothing clear of rotating parts and hot exhaust components.

Fig 6: Inserting Marker Into Piece Of Plastic Pipe

Courtesy of FORD MOTOR CO.

Repeat the marking procedure.
Have the assistant stop accelerating and shut off the engine.
With the driveshaft stationary, observe the mark on the driveshaft. If the new mark is 360 degrees, reinstall all components and road test the vehicle. If the vibration is reduced, move the weighted nut to the adjacent bolts and repeat the marking procedure. If the condition does not improve, install a new driveshaft assembly. Retest using the marker and weighted nuts as necessary. When the best possible condition is met, reinstall all components and road test the vehicle.