sounds to me like your center diff self welded itself. not uncommon. especially if you drove car with space saver.

symptoms would be drivetrain chatter as front wheels move faster that rear when you turn. will feel like brakes are on during coasting. the bigger difference between tire sizes front to rear the bigger the brakes. even brand new tires would be different sizes after just 200 miles. went through these pains with welded diff in yellow car years ago. this is why I dont recommend welded center for street cars.