Following the renaming of the model line, Gillig introduced the Low Floor as an expansion of its product range, marketed alongside the step-entrance Phantom.

A suburban configuration was introduced alongside the standard transit Low Floor (replacing the version previously offered on the Gillig Phantom).

Distinguished by its lack of a rear entry door, the suburban Low Floor was configured with forward-facing seating, internal luggage racks, onboard Wi-Fi, and other passenger-related options.

[8] Of the two body configurations for low-floor buses, the Gillig Low Floor is a low-entry bus (the front two-thirds to three-fourths of the interior is low-floor) with a low-step entry (nearly curb height) and integrated manual wheelchair ramp while the rear part of the interior (behind the rear axle) is raised to provide sufficient space for the powertrain.

The Gillig Low Floor is produced in three nominal body lengths in its standard transit bus configuration: 40 ft (12.2 m).

In 2008, the Allison hybrid drivetrain was 81% more expensive than a conventional bus, which was partially subsidized by federal grants and expected savings in fuel and maintenance costs.

[10]: 30 A fully electric configuration was introduced in 2019, with serial production commencing in 2020;[6] it was developed as a prototype at the request of Big Blue Bus, (who was the lead customer for the model[19][20]) which had reduced an order of 20 CNG buses to 19 in order to test an all-electric powertrain system developed by Cummins (branded "Cummins Battery Electric System").

[23] As tested by the Bus Research and Testing Center in Altoona, a 40-foot (12.2 m) battery-electric bus, with a gross capacity of 444 kW-hr (355 kW-hr usable) at 750 VDC, achieved a range of 129 to 187 mi (208 to 301 km), depending on the driving cycle (Manhattan and EPA HD-UDDS, respectively; the Orange County cycle fell in between).

[24]: 11 Gillig partnered with Kiepe Electric to build 45 "NexGen" trolleybuses for the Greater Dayton Regional Transit Authority (RTA); Gillig was responsible for the chassis, based on the Low Floor BRT/CNG, and Kiepe supplied the traction motor, battery, and trolley pole equipment.

This meant that buses could detour around stalled traffic and the system could be expanded without installing more overhead wire; to facilitate off-wire operation, the driver could move the poles up and down without leaving their seat.

The remaining 41 would be equipped with storage batteries; the prototypes would be tested for more than five years before the first of the 41 regular production models arrived in August 2019.

The vintage-style trolley appearance package exterior features include frameless bonded side windows, maintenance-free wood-like trim, ornate gold pinstriping, custom window and body graphic decals, roof cupola, functional solid brass bell, cow catcher, roof perimeter LED ropelights, and front center brass trolley lamp.

In addition to conventional diesel, the Gillig Trolley is available with optional power trains, including Allison hybrid-electric, all-electric, and CNG.