Some UPS drivers quietly struggle on the job

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In an NBC News investigation, Cynthia McFadden reports on how UPS delivery drivers must work on trucks that are not air-conditioned. She speaks with Jim Klenk, who worked for UPS for almost 15 years -- 10 of them as a driver -- and wound up in the emergency room because his kidneys were failing. We'll have more of his story on tonight's NBC Nightly News broadcast.