How many swift trucks are in US?

According to an FMCSA SAFER state query on 6 December 2014, the company has 17,989 power units. Now, bear in mind that this will include any registered vehicle belonging to the company with a GVWR in excess of 10,000 lbs., so that'll include roadside service trucks, mobile cranes, even 15 passenger vans. But you can expect at least 90-95% of those power units to be semi tractors.