Ah here we go:
NYCDOT - Oversize/Overweight Permits for Commercial Vehicles and Trucks
Anything over 96" wide and combo of 55 feet or longer is considered "oversize" and needs a day pass.
more specific:
http://www.nyc.gov/html/dot/html/permits/commperm.shtml
http://www.nyc.gov/html/dot/downloads/pdf/vehdimen.pdf