When using shims on the rear axle to adjust camber/toe, excessive changes cause added stress on the bolts, due to the head of the bolt not sitting flat on the stub axle. We recommend using the alignment washer kit anytime either the toe or camber has a 1.5 degree change or larger.
Looking at the second picture above shows the comparison with and without the alignment washers. Without the alignment washers only one corner of the bolts will make contact, causing all the force from the bolt head to be spread over a small area, resulting in a stress riser as can be seen in red. When using the alignment washers you can see the force from the bolt head is spread evenly over a larger area, thus not resulting in a high stress concentration.
The Spherical Alignment Washer Kit includes:
4 - Alignment Washer Pairs
4 - Longer Bolts (Grade 10.9)
Each kit will cover one side of the vehicle, so if you need one for both the left and right rear, you will need to order two kits.