# Gillig Low Floor

The Gillig Low Floor (originally named Gillig H2000LF and also nicknamed Gillig Advantage) is a transit bus manufactured by Gillig since 1997. Introduced as a second product range by the company (alongside the Gillig Phantom), the Low Floor later replaced the Phantom entirely. Since 2008, the model line has become the sole vehicle platform produced by Gillig.
The Low Floor was the second low-floor bus design introduced in the United States, following the New Flyer Low Floor. During the 2000s, the configuration came into wide use by transit operators in place of previous high-floor designs. Along with several lengths and body styles, the Low Floor is offered with several different powertrain options, including options for diesel engines, diesel-electric hybrid, compressed natural gas, and battery-electric powertrains.
The Low Floor is currently assembled by Gillig at its Livermore, California facility; prior to 2017, the vehicle was assembled in Hayward, California.

## Design history

The Gillig Low Floor began life in the mid-1990s as Gillig was approached by Hertz Corporation, who sought a shuttle bus for its airport locations (to replace its fleet of GMC RTS buses). Featuring a carpeted interior, luggage racks, and a central entry door, the primary design requirement of Hertz was a low-floor entry for those carrying luggage or with limited mobility. In 1996, the first buses for Hertz (named the Gillig H2000LF) entered production, with Hertz placing the H2000LF in service at Logan International Airport in Boston (expanding to other airports in the United States). Gillig would produce the H2000LF for Hertz through 2005, as the design was replaced by standard Gillig Low Floor buses.
In 1997, Gillig developed the H2000LF shuttle bus into the Low Floor transit bus. Several changes were made to the design, distinguished primarily by the reconfiguration of the entry doors (replacing the central entry with dual entry doors).
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.
* Selected updates and variations
* H2000LF (1998) for Hertz; note large, printed destination/headsign and center door
* Low Floor (2006) for SORTA; note smaller headsign; top of windshield now aligned with top of sliding side windows
* Low Floor (2014) for SamTrans; note larger door glass (square corners) and frameless side windows
* Low Floor (2014) for VTA, suburban configuration
During its production, the Low Floor has undergone several revisions to its body design. In 2002, the windshield was enlarged (with the use of a smaller destination sign) and the side windows were reduced in width. After 2003, the rear side split windows that were configured upside down were reconfigured to match the rest of the side windows; frameless windows later became an option (with or without split openings).
In 2005, the Low Floor model line was expanded by the addition of the Low Floor BRT, adding restyled front and rear bodywork and a front roof fairing; the Trolley Replica (not a trolleybus) restyled the standard Low Floor body as a vintage trolley.
In 2008, the entry doors were revised, adopting larger glass panels (distinguished by squared-off corners). 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.
For 2011, the Low Floor BRT Plus was introduced. Coinciding with the introduction of CNG and diesel-electric hybrid powertrains, the Plus adopted a full-length body fairing to accommodate CNG tanks and hybrid equipment on the roof. In 2017, a Low Floor Plus was introduced, combining the roof fairing of the BRT Plus with the body of the standard Low Floor.
A battery-electric powertrain developed by Cummins was made available for the Low Floor Plus variant starting in 2019. The launch client for the Gillig/Cummins battery-electric bus was Big Blue Bus, serving Santa Monica, California. A battery-electric Low Floor (29-foot) was tested at Altoona in 2018, using a drivetrain adapted from the BAE HybriDrive powertrain.
In April 2024, Gillig announced a hydrogen fuel cell variant of the bus, beginning production in 2026.

## Overview

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). Maximum seating capacity is 40 passengers for the 40-foot length. The turning radius of the Gillig Low Floor is 43 ft (13.1 m) (40 foot body).

### Powertrain
#### Conventional (internal combustion)

Currently (as of 2019 production), the Gillig Low Floor range is equipped with three engines: the Cummins B6.7 diesel, Cummins L9 diesel, and Cummins L9N compressed natural gas inline-six engines. Throughout its production, the Gillig Low Floor has featured a range of Cummins engines along with Caterpillar and Detroit Diesel engines.
Allison, Voith, and ZF automatic transmissions are available.

#### Diesel-electric hybrid

Since 2004, the Gillig Low Floor has been available in a diesel-electric hybrid configuration with the Cummins ISB engine; hybrid models are identified by their roof-mounted battery pack. Hybrid models have been produced with Allison, BAE, and Voith series- and parallel-hybrid powertrains. 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.
The Gillig/Voith hybrid, branded DIWAhybrid, is a mild parallel hybrid system using Maxwell ultracapacitor on-board energy storage, and was tested to have an observed overall average fuel consumption of 4.75 mpg$_{‑US}$ (49.5 L/100 km; 5.70 mpg$_{‑imp}$).$^{:62}$ The Gillig/BAE series hybrid, branded HybriDrive, had comparable fuel consumption, at 4.64 mpg$_{‑US}$ (50.7 L/100 km; 5.57 mpg$_{‑imp}$) (40-foot)$^{:50}$ and 3.96–6.14 mpg$_{‑US}$ (59.4–38.3 L/100 km; 4.76–7.37 mpg$_{‑imp}$) (40-foot, Manhattan and HD-UDDS driving cycles, respectively).$^{:31}$ The Gillig/Allison dual-mode (series/parallel) hybrid was similar, at 3.64–6.40 mpg$_{‑US}$ (64.6–36.8 L/100 km; 4.37–7.69 mpg$_{‑imp}$) (40-foot (12.2 m), Manhattan and HD-UDDS driving cycles).$^{:30}$

#### Battery electric

A fully electric configuration was introduced in 2019, with serial production commencing in 2020; it was developed as a prototype at the request of Big Blue Bus, (who was the lead customer for the model) 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"). The buses use plug-in charging with a SAE J1772 CCS Type 1 connector, and an overhead pantograph (SAE J3105–1) connection is available.
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).$^{:11,92}$ Observed energy consumption was 3.04 kW⋅h/mi (11.1 mpg‑e) (Manhattan), 2.27 kW⋅h/mi (14.8 mpg‑e) (Orange County), and 2.09 kW⋅h/mi (16.1 mpg‑e) (HD-UDDS).$^{:87}$ The Cummins TM4 traction motor had a rated output of 262.5 to 562.5 kW (352 to 754 hp).$^{:11}$

#### Trolleybus

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. The contract was awarded by RTA in 2013 and the resulting buses featured "in-motion charging", using the trolley wires to charge an on-board battery that provided an off-wire range of up to 20 mi (32 km). 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. Four prototypes were supplied in 2014: two used diesel engines to operate off-wire, while the other two used storage batteries. 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 final bus was delivered in September 2020.

#### Hydrogen Fuel Cell

Announced in 2024 with production beginning in 2026, this variant comes in two variants with ranges of either 320 or 375 miles (515 or 604 km) using Ballard fuel cells.

### Engine and Transmission Options

The Gillig Low Floor series is currently and formerly available the following engine and transmission options:
Engines :
| Engine | Fuel | Production | Availability | Notes |
| Caterpillar C9 | Diesel | 2003–2009 | BRT Trolley | |
| Cummins C8.3 | Diesel | 1996–1998 | Low Floor | |
| Cummins ISB | Diesel | 2008–present (ISB6.7) 2004–2007 (ISB) | BRT Trolley | Used for diesel-electric hybrid powertrains |
| Cummins ISC | Diesel | 1998–2003 | Low Floor | |
| Cummins ISL | Diesel | 2001–2010 | H2000LF Low Floor BRT Trolley | |
| Cummins ISL9 | Diesel | 2011–2016 | H2000LF Low Floor BRT Trolley | |
| Cummins L9 | Diesel | 2017–present | H2000LF Low Floor BRT Trolley | King County Metro diesel-electric hybrid versions use this engine instead of Cummins ISB6.7 |
| Cummins Westport ISL G | CNG | 2010–2017 | Low Floor BRT | |
| Cummins Westport L9N | CNG | 2017–present | Low Floor BRT | |
| Cummins M11E | Diesel | 1996–1999 | Low Floor | |
| Cummins ISM | Diesel | 1999–2009 | Low Floor BRT Trolley | |
| Cummins | Electric | 2019+ | Low Floor Plus | Permanent magnet traction motor; peak/continuous power and torque: 350 / 225 kW (469 / 302 hp; 476 / 306 PS) and 3,400 / 850 N⋅m (2,510 / 630 lb⋅ft) |
| Detroit Diesel Series 40E | Diesel | 1997–2003 | H2000LF Low Floor | Also known as the Navistar DT530E engine |
| Detroit Diesel Series 50 | Diesel | 1996–2005 | Low Floor | |
| Ford Triton V10 | Gasoline | 2009 | BRT | Gillig BRT only Produced in a single order of gasoline-hybrid buses for LeeTran. |
| Vossloh-Kiepe | Trolleybus | 2014–2021 | BRTPlus | For Dayton RTA's trolleybus system |
| Transmissions |||||
| Transmission | Transmission | Production | Availability | Notes |
| Allison B300R | Allison B300R | 1996–present | All | |
| Allison B400R | Allison B400R | 1996–present | All | |
| Voith D863.3 / D864.3 Voith D863.3E / D864.3E | Voith D863.3 / D864.3 Voith D863.3E / D864.3E | 1996–2005 | H2000LF Low Floor | |
| Voith D864.5 | Voith D864.5 | 2005–present | BRT Trolley | |
| ZF 5/6HP592C | ZF 5/6HP592C | 2001–2007 | Low Floor BRT Trolley | |
| ZF 5/6HP594C | ZF 5/6HP594C | 2007–2010 | Low Floor BRT Trolley | |
| ZF Ecolife | ZF Ecolife | 2010–present | Low Floor BRT | |
| Allison E$^P$40/H 40 EP | Allison E$^P$40/H 40 EP | 2004–present | Low Floor BRT Trolley | Parallel diesel-electric hybrid powertrain |
| BAE Systems HybriDrive | BAE Systems HybriDrive | 2011–present | Low Floor | Series diesel-electric powertrain |
| ISE Corporation ThunderVolt | ISE Corporation ThunderVolt | 2009 | BRT | Gasoline-electric hybrid (Ford V10) |
| Voith DIWAhybrid | Voith DIWAhybrid | 2008–present | Low Floor BRT Trolley | Parallel diesel-electric hybrid powertrain |

## Variants

Gillig Low Floor variants :
| Name | Intro. | Changes |
| BRT | 2005 | Extended front fascia Restyled rear fascia Projector headlights |
| BRT Plus | 2011 | Extended front fascia Full-length roof fairing Projector headlights |
| Low Floor Plus | 2017 | Full-length roof fairing |
| Trolley Replica | 2005 | Heritage trolley appearance |
Gillig also manufactures four models of buses based on the Low Floor chassis: the Low Floor BRT, Low Floor BRT Plus, Low Floor Plus, and the Low Floor Trolley. All have the same engine and transmission options as the standard Low Floor.

### Gillig BRT

The Gillig BRT is a restyled version of the Low Floor with different front and rear fascias. It wears a more futuristic look than the standard model. It is available in the same lengths as the standard Low Floor model, although the front fascia adds roughly an extra foot of length to the bus. Instead of sealed-beam headlights, the Gillig BRT has projector headlights. The Gillig BRT is available with CNG, Diesel and Diesel-Electric Hybrid drivetrains.

### Gillig BRT Plus

The Gillig BRT Plus is a variant of the BRT which features a full-length roof fairing which hides equipment which can include A/C units, CNG fuel tanks, or batteries. The Plus made its debut in 2011 with Long Beach Transit #1201, which is also the first Compressed Natural Gas (CNG) BRT produced.

### Gillig Low Floor Plus

The newest variant of the Gilig Low Floor. Introduced in 2017, the Low Floor Plus is more mildly restyled compared to the Gillig BRT and BRT Plus. The Low Floor Plus features the headlights of the BRT and full-length roof fairings similar to the BRTPlus, but retains the same windshield and rear end cap as the traditional Low Floor model.

### Gillig Trolley Replica

The Gillig Trolley is a trolley-replica bus produced in collaboration with Cable Car Classics of Healdsburg, California. It is available in 30, 35 and 40-foot (9.1, 10.7 and 12.2-meter) lengths. 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. The interior has solid American white oak seats, optional seat cushions, leather hand straps, brass handrails, stop request pull ropes, wood trim, and woodgrain wall panels and floor covering. In addition to conventional diesel, the Gillig Trolley is available with optional power trains, including Allison hybrid-electric, all-electric, and CNG.