I have an 89 B350 ext passenger van. A bearing went out, ruined my spindle. I am having a hard time finding a replacement. Especially since I don't know if I have a 3300, 3600 or a 4000 lb axle. I'm assuming it's not a 3300. Does it even matter what which axle I have?

How do I find out which axle I have and which other vehicles have compatible steering knuckles?

I desperately need to get this back on the road.

Thanks!