On Aug 30, 2011, at 8:25 PM, Kevin Gilbert wrote:

> Occasionally, and unpredictably, I hear and feel a thwang and snap
> sound from right rear, usually when making a turn.
> 
The first thing that comes to mind is a broken spring. Fairly easy to examine by
loosening the RR top shock nut so the shock can let the wheel go to full droop.
Jack the van up, remove the wheel, be sure the emergency brake is off or the 
wheel won't go to full droop, and twist and pull and examine that spring.
bob ... you may be able to get a good enough look at the spring with just the wheel
off.