GM was the first automaker to offer factory-installed XM radios in its 2002 Cadillac Devilles and Sevilles last fall.
XM radios will be available in 2003 model year vehicles including Buick Rendezvous, Cadillac Escalade, Chevrolet Cavalier, GMC Yukon, Oldsmobile Alero and Pontiac Aztek.
XM, which broadcasts 100 digital-quality, coast-to-coast channels for $9.99 a month, last week announced it has 30,000 subscribers since its national rollout last fall.
GM is one of XM's financial backers, which also include American Honda Motor Corp., DirecTV, Clear Channel
XM and rival Sirius Satellite Radio also have distribution agreements with Porsche Cars North America to offer radios in its models next year for the 2004 line.
Sirius, which plans to launch its service next month, also has partnerships with BMW of North America, DaimlerChrysler and Ford Motor Co.