Coleman had an issue with the 2007 and half of 2008 Niagara and Avalon with an oversized motor for the roof lift system that would put so much pressure on the whiffletree that it would cause it to break.  Which would make a large banging noise, having the roof drop up to 18 inches and putting the camper out of commission.

This was a recall back when Coleman was still in business but they ceases operations at the Somerset plant on Jan. 19, 2011.
Recall Number: 07V464000

The original recall was adding several stickers to the camper:
"ON CERTAIN RECREATIONAL VEHICLES, THE POWER LIFT ROOF SYSTEM, WHICH CONSISTS OF A POWER LIFT MOTOR AND CURRENT LIMITER CONTROLLER, GENERATES EXCESSIVE AMOUNTS OF IMPACT TORQUE IF THE POWER LIFT IS OPERATED WITH THE 30A POWER CORD PLUGGED INTO A 110V AC POWER SOURCE (WITH OR WITHOUT A BATTERY).
Consequence:
THIS COULD CAUSE FAILURE IN ONE OF THE SHEAR PINS RESULTING IN DAMAGE TO THE TRAILER'S LIFT SYSTEM. THIS COULD ALLOW THE ROOF TO FREE-FALL FROM THE RAISED POSITION, POSSIBLY RESULTING IN PERSONAL INJURY, VEHICLE AND/OR PROPERTY DAMAGE."

The second recall was going to have the recall kit installed for no cost (stickers, new motor and control board). 

Then for the third recall, they just installed a harder metal whiffletree.

If you were interested in a used camper, I don't know how you would know if the recall was performed or not?

Beckley RV in Maryland purchased all remaining Coleman campers and parts during the sale.  They have carried the replacement whiffletree and many others parts.

Model and Year of Campers effected if they have the power roof option:
FLEETWOOD / ARCADIA 2007-2008

FLEETWOOD / AVALON 2007 and half of 2008

FLEETWOOD / BAYSIDE 2007-2008

FLEETWOOD / CHEYENNE 2007

FLEETWOOD / NIAGARA 2007 and half of 2008

FLEETWOOD / SANTA FE 2007-2008

FLEETWOOD / SARATOGA 2007-2008

FLEETWOOD / SEQUOIA 2007

FLEETWOOD / SUN VALLEY 2007-2008

FLEETWOOD / UTAH 2007-2008

FLEETWOOD / WILLIAMSBURG 2007-2008