General Motors has added model-name designations to its all-new conventional-cab line of 2003 Class 4-8 trucks. Previously known only by their GM code name GMT560, they are now known as the 2003 Chevrolet Kodiak/GMC TopKick.The Kodiak/TopKick C4500-C5500 Series (Class 4-5) trucks have been designed and engineered from the ground up for 2003. From regular and commercial cutaway chassis cabs, and even voca-tional packages to cover school bus, fire and rescue, ambulance, shuttle bus, wrecker and snowplow requirements, there are now more specific model choices. New crew cab and four-wheel-drive models will follow. Gross vehicle weight ratings (GVWRs) range from 16,000 lbs. for the C4500 to 18,000 and 19,500 lbs. for the C5500.The new Kodiak/TopKick C6500, C7500 and C8500 Series (Class 6-7-8) trucks replace GM’s conventional-cab C-Series line with regular and crew cab, chassis cab offerings. GVWRs cover 19,501 to 61,000 lbs. The Kodiak/TopKick model-name designations were used on Chevrolet and GMC medium-duty trucks available from the early 1980s through the mid-’90s.