I can't believe that ujoint stayed in.... yikes...
Anyways, I drove my truck home after loosing the rear shaft in 4hi-front wheel drive and encountered no problems in the handling except a bit of shaking that I think is the clutch. And the drive was 2hrs long.
I'd say look at the u-joints. Especially the ones connecting the axle to the stub shaft.
It probably stops after 10mph because of gyroscopic force. Like how a bicycle/motorcycle want to stand up and go straight forward when you're moving.