1997 Chevy blazer front wheel lock when 4 drive is engaged i have repalced rotors brakes and calipers could it be hubs jacked up wheels turn hard like something dragi?

If the front wheels lock up when 4WD is engaged on your 1997 Chevy Blazer, even after replacing rotors, brakes, and calipers, the problem is almost certainly *not* in those components. The fact that the wheels turn hard suggests a binding issue in the drivetrain, not the braking system.

Here are the most likely culprits:

* Transfer Case Problems: The transfer case is the component that distributes power between the front and rear axles. A problem within the transfer case (binding gears, low fluid, internal damage) can cause the front wheels to bind when 4WD is engaged. This is the most probable cause given your description.

* Front Axle Issues: Problems in the front differential or axle shafts can also lead to binding. This could include:

* Differentials: A damaged or binding front differential could cause the wheels to lock.

* CV Joints: Worn or damaged constant velocity (CV) joints will cause binding and clicking/popping noises, often leading to a hard-to-turn wheel.

* Axle Shafts: Bent or damaged axle shafts could also be the source of the problem.

* Hub Assembly: While you mentioned replacing parts, a problem within the wheel hub assemblies themselves (besides the bearings, which usually make noise) isn't entirely out of the question. Something might be interfering with the free rotation of the wheel even with the brakes disengaged.

* Binding in the 4WD Engagement Mechanism: There could be a mechanical issue within the system that engages 4WD, preventing the front wheels from disengaging properly.

Troubleshooting Steps:

1. Engage 4WD in a safe location: Try engaging 4WD on a level surface, preferably with the vehicle stationary. Carefully try to turn the front wheels. If they are extremely difficult to turn, you've confirmed a drivetrain issue, not brakes.

2. Inspect the Driveshafts: Visually inspect the driveshafts for damage, binding, or unusual play.

3. Check Transfer Case Fluid: Check the transfer case fluid level and condition. Low or dirty fluid can cause problems.

4. Listen for Noises: Listen carefully for any unusual noises (grinding, clicking, whining) when 4WD is engaged. This can help pinpoint the location of the problem.

5. Professional Diagnosis: Given the complexity of 4WD systems, it's highly recommended to take your Blazer to a qualified mechanic specializing in 4x4 vehicles. They have the tools and expertise to diagnose the problem accurately and safely. Trying to diagnose and fix this yourself could lead to further damage.

Ignoring this issue could lead to more significant damage to your drivetrain components. Get it checked out as soon as possible.