Here's why:
* Uneven Power Distribution: 4Hi is designed to distribute power evenly to all four wheels. With the rear driveshaft disconnected, you're only powering the front wheels. This can lead to poor handling, especially in slippery conditions. The front wheels may struggle to maintain traction, potentially causing loss of control.
* Increased Wear and Tear: Forcing the front wheels to do all the work can lead to premature wear on the front differential, axles, and tires.
* Potential Drivetrain Damage: Depending on your vehicle's system, driving in 4Hi with a disconnected rear driveshaft could damage the transfer case or other drivetrain components. The system might be designed to detect the disconnect and prevent damage, but this isn't guaranteed.
* Reduced Stability: Loss of rear-wheel drive significantly reduces vehicle stability, particularly during turns or on uneven surfaces.
In short: If your rear driveshaft is disconnected, you should only drive in 2-wheel drive (2WD). Get the driveshaft repaired or replaced before attempting to use 4-wheel drive. Ignoring this can lead to accidents and costly repairs.
