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Driveline Working Angles Measurement - part 2

Rating:
The weight of 3.8-L(1-gal) of gasoline is approximately 2.8-kg(6.2-lb).Raise and support the vehicle. On vehicles with solid axles,ensure that the drive axle is supported at rideheight—vehicle body supported by suspension components.Suspension travel will not affect driveline angles on vehicles withdirect-mounted drive axles. Ensure the wheels are free to rotate.Refer toLifting and Jacking the Vehicle.For vehicles with 2-piece prop shaft systems, inspect thelateral alignment of the propeller shafts before proceeding:From underneath the propeller shafts, look down the length ofthe shafts from front to rear. Inspect the alignment of the shaftsto each other.From underneath the shafts, if the propeller shafts are notaligned to each other in a straight line, then the lateralalignment of the prop shafts needs to be adjusted beforeproceeding.

The propeller shaft support bearing assembly can be relocatedslightly to one side in order to improve the alignment of theshafts. Ensure that you do not create a ground-out conditionagainst the exhaust or any other component.

Place the transmission in NEUTRAL.Clean any corrosion or foreign material from the U-jointbearing caps.Remove any of the U-joint bearing cap snap rings that mayinterfere with the correct placement of theJ-23498-ADriveshaft Inclinometer, or equivalent .

Driveline Working Angles Measurement

For all prop systems perform the first measurement:Rotate the prop shaft to align the rear-most yoke flangesvertically.Install theJ-23498-ADriveshaft Inclinometer, or equivalent to the lower U-joint bearing cap of therear-most yoke. This yoke may be part of a prop shaft, torque tubeinput shaft, or a drive axle pinion shaft. Measure and record theangle of the shaft.For prop systems with 2-or 3-U-joints,perform this additional measurement:

Without rotating the prop, install theJ-23498-ADriveshaft Inclinometer, or equivalent to the lower U-joint bearing cap of theforward-most, vertically-aligned yoke. This yoke may be part of aprop shaft, transmission output shaft, or a transfer case outputshaft. Measure and record the angle of the shaft.

For all prop systems perform the second measurement:Rotate the prop shaft 1/4-turn to vertically alignthe flanges of the forward yoke that mates to the rear-mostyoke.Install theJ-23498-ADriveshaft Inclinometer, or equivalent to the lower U-joint bearing cap of theforward mating yoke. This yoke may be part of a prop shaft,transmission output shaft, or a transfer case output shaft. Measureand record the angle of the shaft.For prop systems with 3-U-joints, perform thisadditional measurement:

Without rotating the prop, install theJ-23498-ADriveshaft Inclinometer, or equivalent to the lower U-joint bearing cap of theforward-most, vertically-aligned yoke. This yoke may be part of atransmission output shaft, or a transfer case output shaft. Measureand record the angle of the shaft.

Remove theJ-23498-ADriveshaft Inclinometer, or equivalent .Install any U-joint bearing cap snap rings that were removedprior to installing theJ-23498-ADriveshaft Inclinometer, or equivalent .Calculate the U-joint working angle at each intersection oftwo shafts.

Subtract the smaller number from the larger to obtain theworking angle.For example: If the drive axle pinion has an angleof 16-degrees and the connecting propeller shaft has anangle of 13-degrees, then the working angle of thatintersection is 3-degrees.

For prop systems with 1-U-joint; compare theworking angle to the following specification guideline:

Specification Guideline

Prop systems containing only 1-U-joint: TheU-joint working angle should be between 1/2-and3/4-degrees.For prop systems with 2-or 3-U-joints;compare the difference between the working angles of the cancellingU-joints to the following specification guidelines:

Specification Guideline

Allowable range of difference between cancelling U-jointworking angles: 0.25-to 1.0-degreesFor prop systems with 3-U-joints; compare theworking angle of the odd, or non-cancelled U-joint to the followingspecification guideline:

Specification Guideline

Prop systems containing 3-U-joints: The odd, ornon-cancelled U-joint working angle should be between1/10-and 1/2-degrees.Any working angle that is not within the specificationguidelines requires adjustment.

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