One problem related to engine exhaust system has been reported for the 2008 Chevrolet C4500. The most recently reported issues are listed below.
Problem with engine shutting down with no warning. Has happened countless times. Has been in for repair several times but problem still exists. The problem is the diesel particulate filter regeneration #pip4598. It sets code 244b which shuts the engine down to 2000 rpm max. This is a significant safety issue as it will slow to a crawl in traffic. On 3/14 on I-95 in new york city, the regen light recurred (code 244b). I could barely get out of traffic and came close to a serious accident.