Heavy Duty Trucking Logo
MenuMENU
SearchSEARCH

GHG Phase 2 Glider Kit Restrictions to be Enforced After All

After a court challenge stymied its efforts to give makers of glider kits a reprieve from challenged provisions of its greenhouse gas regulations, the Environmental Protection Agency has withdrawn an order to not enforce those regulations against small manufacturers of glider kits.

Deborah Lockridge
Deborah LockridgeEditor and Associate Publisher
Read Deborah's Posts
July 27, 2018
GHG Phase 2 Glider Kit Restrictions to be Enforced After All

Glider kits allow older engines and drivetrains to be re-used in new truck cabs, but environmental advocates say they are a dangerously polluting loophole to federal emissions rules.

Photo by Deborah Lockridge

4 min to read


After a court challenge stymied its efforts to give small manufacturers of glider kits a reprieve from challenged provisions of its greenhouse gas regulations, the Environmental Protection Agency has withdrawn an order to not enforce those regulations.

On July 6, the EPA said it would not enforce a 300-unit production cap put in place on the manufacture of glider kits/vehicles that do not comply with Phase 2 GHG emission rules. The aim was to protect “small” manufacturers of glider kits as defined by the Small Business Administration. This was on the eve of the departure of EPA Administrator Scott Pruitt, under fire for allegations of unethical behavior.

Ad Loading...

However, by July 18, a federal court had granted a temporary stay suspending that decision, in response to a motion for an emergency stay by environmental groups.

The environmental groups argued in their brief that the decision not to enforce should be declared unlawful and be vacated because the EPA’s action is “an illegal effort to subvert the Clean Air Act” and “the Glider Decision is arbitrary and capricious.” The three petitioning groups contended that the Phase 2 GHG emissions are current law and were adopted after years of analysis and public comment.

Following the court ruling, late on July 26, Acting EPA head Andrew Wheeler withdrew the agency’s non-enforcement order.

Ad Loading...

“I have concluded that the application of current regulations to the glider industry does not represent the kind of extreme unusual circumstances that support the EPA’s exercise of enforcement discretion,” Wheeler wrote in a memo released late Thursday night. He cited the court decision, as well as a 1995 internal EPA policy that sought to greatly restrict how often EPA decides not to enforce regulations on the books.

EPA’s withdrawal also follows legal action by a broad coalition of 16 state Attorneys General who opposed the non-enforcement policy.

The GHG Phase 2 rule aimed to limit glider kits to their original purpose of allowing truck owners to repair wrecked vehicles. Instead, truck owners have increasingly used them to have the benefits of new-truck cabs and aerodynamics while using older, more-polluting engines that owners said were more reliable than maintenance-plagued low-emissions engines. Many saw this as a dangerous loophole in federal emissions rules, so it was addressed in the final GHG rule.

In 2017, a number of petitions were filed, most notably by Fitzgerald Glider Kits, saying the EPA’s action was regulatory overreach and that it did not have the authority to regulate these types of vehicles. In response, the EPA issued a regulatory proposal last November to reconsider the glider kit restrictions.

There has been controversy over two separate studies showing very different pollution results from glider kits. One that the EPA cited in its reconsideration of the rule was funded by Fitzgerald and later withdrawn by the university that performed it. The other was done by the EPA, but Fitzgerald and others raised concerns that truck and engine maker Volvo may have had undue influence in that testing.

Ad Loading...

The Environmental Defense Fund commissioned an analysis and submitted it as part of its court filings that indicates the additional glider trucks produced during EPA’s two-year non-enforcement policy could result in more than 1,700 premature deaths over the life of those vehicles.

Meanwhile, some glider kit makers, such as Freightliner, have decided to go ahead with their planned phase-down of glider kit production no matter what the final outcome is, saying they are abiding by the spirit of the GHG2 rules.

“This is a huge win for all Americans who care about clean air and human health,” said EDF President Fred Krupp. “These super-polluting diesel freight trucks fill our lungs with a toxic stew of pollution. EPA’s effort to create a loophole allowing more of them onto our roads was irresponsible and dangerous. We hope their decision tonight to withdraw that loophole puts a firm and final end to this serious threat to our families’ health.”

Sen. Tom Carper, the top Democrat on the Environment and Public Works Committee, also praised the decision. “With Mr. Pruitt out, I’m glad to see EPA will reverse one of the most egregious — and likely illegal — environmental proposals of his tenure,” Carper said in a statement. “His senseless proposal ignored the science put out by his own EPA and created a Clean Air Act loophole for an industry friend, all while putting the health of Americans and our environment at risk.”

What is not clear at this point is what will happen to the EPA’s proposed rule to permanently repeal the glider kit portion of the GHG regulations.

More Fuel Smarts

A GP Transco tractor-trailer crosses a bridge over a river, with trailer side skirts visible beneath the white trailer.
Fuel Smarts•by Deborah Lockridge•October 27, 2026

How GP Transco Builds Fuel Savings a Fraction at a Time

Aerodynamic specs, solar panels, and driver incentives help GP Transco turn small efficiency gains into savings it can reinvest in its people.

Read More →
Man on large stage with American Trucking Associations logo in the background and large screen displays of distillate stocks.
Fuel Smarts•by Deborah Lockridge•October 20, 2026

Trucking’s Diesel Squeeze Isn’t Letting Up

With diesel topping $6 a gallon nationally, ATA's Bob Costello explains why fleets should prepare for continued pressure at the pump.

Read More →
Computer rendering showing airflow around a trailer’s tandem wheels equipped with FlowBelow AeroSlider fairings and wheel covers.
Fuel Smarts•by Deborah Lockridge•October 18, 2026

FlowBelow Redesigns Trailer AeroSlider to Cut Fuel Use

The lighter trailer aerodynamic system installs in less than 45 minutes, according to the company, with potential payback in under a year depending on fuel prices and trailer mileage.

Read More →
Ad Loading...
Illustration with oil wells, dollar bills, and a diesel fuel pump
Fuel Smarts•by Deborah Lockridge•October 14, 2026

Why Diesel Price Relief Efforts May Fall Short

Diesel prices have eased from September’s record high, but doubts about additional Russian supply and limits on dyed-diesel tax relief mean trucking fleets still face expensive fuel. And prices could go higher.

Read More →
Video thumbnail with text: Fuel -- small gains, big savings.
Fuel Smarts•October 12, 2026

Why Small Fuel Savings Matter in Trucking

Can better fuel economy help pay for driver raises? In this podcast, GP Transco explains how small efficiency gains create room to reinvest in its people.

Read More →
Youtube thumbnail showing two people with a truck and the word "fuel" behind them, the HDT Talks Trucking logo, and the words "Small Gains. Big Savings."
Fuel Smarts•by Deborah Lockridge•October 12, 2026

How GP Transco Cuts Trucking Fuel Costs, a Tenth of a Gallon at a Time

What’s another tenth of a mile per gallon worth? GP Transco shares how equipment upgrades and driver coaching turn small gains into meaningful fuel savings.

Read More →
Ad Loading...
Photo of electric OrangeEV terminal tractor with a Lazer Logistics trailer
Equipment•by Staff•October 6, 2026

Electric Yard Tractors Move Beyond Pilots

Operating-cost savings have overtaken sustainability goals as the leading reason surveyed fleets are adopting battery-electric terminal tractors, according to new NACFE research.

Read More →
Illustration of map with GPS markers overlaid with Geotab fleet card and a fuel pump nozzle
Fuel Smarts•by Staff•October 2, 2026

Geotab Links Fleet Card to Vehicle Data

The new card combines fuel discounts with telematics-based purchase controls. Geotab’s analysis also points to potential savings from choosing lower-priced fuel stops.

Read More →
White Tesla Semi electric truck on display on a show floor
Equipment•by Staff•September 30, 2026

Fleet Economics Shape Electric Truck Outlook

ACT Research expects costs, charging infrastructure, and technology improvements to drive zero-emission commercial vehicle adoption as federal regulations and incentives retreat.

Read More →
Ad Loading...
Male truck driver in flannel shirt by truck using his smartphone
Fuel Smarts•by News/Media Release•September 23, 2026

Wex Adds Cardless Fuel Payments for Over-the-Road Customers

A new fuel card feature for Wex customers offers convenience and security.

Read More →