(Tl,dr 98 mustang gt automatic, nasty crash snapped the end of the axle off, replaced with a junkyard axle, messed with the spider gears in the diff to get the cross pin back in, got everything buttoned up started her up, when you hit the gas the wheels don’t turn until you hit 2000 rpm)

So I have a 1998 mustang gt, it has many problems, the latest is 150% my fault. I was being stupid and smacked my rear drivers side wheel into a curb after swerving, no one was hurt but I snapped the end...

Snapped the rear axle, replaced it, but now the wheels won’t spin until I hit 2000 rpm.