Aside from a few buses bodied by Corbeil in the late 1990s, this chassis has been used exclusively by AmTran and its Navistar corporate successor IC Bus.

Just like the FE, the RE would be redesigned in 2003 after the rebranding of AmTran to IC Bus.

Introduced as the replacement for the long-running International Harvester 1853FC forward-control chassis, the 3900 was first produced in 1990.

The warning light caps and the back were redesigned after AmTran renamed themselves to IC Bus in 2003.

As Navistar abandoned its use of MaxxForce engines (due to the use of EGR emissions treatment systems), the company announced that the MaxxForceDT was replaced by the Cummins L9 for 2017 production.