Tools Required
The working angle of a U-joint is formed by the difference between the angles
of two shafts that intersect. One-piece propeller shaft systems have two working angles;
front (1) and rear (2).
• | The front working angle (1) is formed by the intersection of the
transmission output shaft and the propeller shaft. |
• | The rear working angle (2) is formed by the intersection of the
propeller shaft and the drive axle pinion. |
When measuring and evaluating driveline working angles, observe the following:
• | The two working, or cancelling angles should be equal to each other within
1/2 degree to provide effective cancellation of the U-joints. |
• | No working angle should exceed 4 degrees. |
• | No working angle should be equal to zero. An angle of 0 degrees
will cause premature U-joint wear due to a lack of rotation of the needle bearings
in the U-joint. |
• | Always orientate the J 23498-A
so that it faces the same side of the vehicle for each measurement taken. |
• | Be sure to accurately record the measurements
taken on a diagram, similar to the one shown. |
Measurement Procedure
Important: If it is necessary to use the J 23498-20
adapter, first verify the accuracy of the J 23498-20
by inspecting the angle of an accessible
joint using the J 23498-A
, then
inspecting the same joint angle using the J 23498-20
.
- Raise and support the vehicle. Ensure that the drive axle is supported
at ride height - vehicle body supported by suspension components - with
the wheels free to rotate. Refer to
Lifting and Jacking the Vehicle
in General Information.
- Place the transmission in NEUTRAL.
- Ensure that the vehicle has a full tank of fuel or the equivalent amount
of weight in the rear to simulate a full tank. The weight of 3.8 L (1 gal)
of gasoline is approximately 2.8 kg (6.2 lb).
- Clean any corrosion or foreign material from the U-joint bearing caps.
- Remove any of the U-joint bearing cap snap rings that may interfere with
the correct placement of the J 23498-A
.
- Measure the angle of the drive axle pinion.
6.1. | Rotate the drive axle pinion to align the pinion yoke flanges vertically. |
6.2. | Install the J 23498-A
to the lower U-joint bearing cap of the drive axle pinion. |
6.3. | Using the J 23498-A
,
measure and record the angle of the drive axle pinion. |
- Measure the angle of the transmission output
shaft yoke.
7.1. | Do not rotate the propeller shaft. With the propeller shaft in the same
position, the transmission output shaft yoke flange will be aligned vertically. |
7.2. | Install the J 23498-A
to the lower U-joint bearing cap of the transmission output shaft yoke. |
7.3. | Using the J 23498-A
,
measure and record the angle of the transmission output shaft yoke. |
- Rotate the propeller shaft 1/4 turn.
- Measure the angle of the propeller shaft.
9.1. | Do not rotate the propeller shaft. With the propeller shaft in this position,
the U-joints of the propeller shaft will be aligned vertically. |
9.2. | Install the J 23498-A
to the lower U-joint bearing cap of either of the U-joints on the propeller shaft. |
9.3. | Using the J 23498-A
,
measure and record the angle of the propeller shaft. |
- Remove the J 23498-A
.
- Install any U-joint bearing cap snap rings that were removed prior to
installing the J 23498-A
.
- Calculate the working angles at each intersection of two shafts.
Subtract the larger number from the smaller to obtain the working angle. For
example: If the drive axle pinion has an angle of 16 degrees and the connecting
propeller shaft has an angle of 13 degrees, then the working angle of that
intersection is 3 degrees.
- Compare the working angles of cancelling U-joints, beginning at the rear-most
position.
- If the working angles of two cancelling U-joints are not within 1/2 degree
of each other, or if one or both of the angles exceed 4 degrees, then the angle
requires adjustment.