There is not enough adjustment left to correct rear camber and rear toe on a vehicle. Which of the following could be the cause?

The scenario where there is insufficient adjustment left to correct rear camber and rear toe can often be attributed to sagging rear springs. When rear springs sag, they lose their ability to maintain the intended ride height and can also change the geometry of the suspension system. This alteration can affect alignment angles, including camber and toe, making it difficult to achieve the manufacturer's specifications through standard adjustments.

As the springs age, they may no longer function as designed, leading to increased negative camber or incorrect toe settings due to the misalignment of related components. Therefore, emphasis on sagging rear springs as the cause in this context directly correlates with the inability to adjust the rear alignment effectively.

Worn shock absorbers, whether on the front or rear, typically impact the vehicle's handling and ride quality rather than directly affecting alignment adjustment limits. Similarly, sagging front springs may lead to issues in the front suspension but would not have a direct impact on the rear camber and toe adjustments.