* Axle Housing: The 4x4 Tahoe requires a wider axle housing to accommodate the larger differential and the necessary space for the driveshafts. A 4x2 axle is significantly narrower.
* Differential: The 4x4 differential is designed to handle the torque split to both axles. A 4x2 differential only handles torque to the rear wheels. Even if the gear ratio (3.42) is the same, the internals are different and not interchangeable.
* Mounting Points: The mounting points on the frame and suspension will not align. The 4x4 Tahoe uses a different suspension geometry and mounting locations for the rear axle.
* Brakes: The brake components might not be compatible. While it's possible the brake *rotors* might bolt on, the calipers and other parts may not be directly interchangeable.
* ABS: If your Tahoe has anti-lock brakes (ABS), the sensors and wiring for the rear axle might not match a non-ABS 4x2 axle.
In short, while the gear ratio might be a match, the entire axle assembly is different and incompatible. You would need a rear axle assembly specifically designed for a 4x4 1997 Tahoe. Trying to force a 4x2 axle into a 4x4 vehicle would be a major undertaking and would likely not work safely or correctly.
