General Motors Corp. is expected to unveil plans this summer for building a Class C motorhome chassis with a gross vehicle weight rating (gvwr) above 15,000 pounds beginning in 2002.

Details about the GMT560 program might be revealed as soon as June 3, during GM’s upfitters meeting in Las Vegas. Motorhome manufacturers have been invited to the van converters gathering.

Currently, Ford Motor Co. dominates the Class C market because it supplies a chassis with a 14,000-pound gvwr. However, Ford chassis have become scarce in recent months due to capacity constraints caused by strong retail demand for several Ford sport utility, truck and van products.

Consequently, motorhome builders have been hopeful that GM, the only other Class C chassis supplier, would begin producing a Class C chassis with a gvwr above the 12,300 pounds that it currently offers.