Sales of the 2017 Mercedez-Benz GLS350d are on hold in the U.S. while it awaits a certificate of compliance from the EPA, a Mercedes-Benz spokesman said this week.

The diesel SUV, which is the automaker's base offering in the GLS range, is slightly different than the 2016 version that was sold last year and hasn't yet been approved for sale by the environmental agency.

"As you’re aware, emissions certification—especially for diesels—has been a hot topic," Mercedes spokesman Brian Cotter said in an email.

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"As a result, regulatory agencies around the world (including the EPA) are taking a closer look at the certification process for all new vehicles (including diesels) which causes some delays in launch timelines."

The 3.0-liter turbodiesel V-6 has been the target of two separate lawsuits from the same law firm alleging that the engine could emit more nitrogen oxides than permitted when cold.

The EPA asked parent company Daimler in February to submit further information about emissions from its engine as a result from the first lawsuit, according to Reuters.

2013 Mercedes-Benz GL Class, 2012 New York Auto Show

2013 Mercedes-Benz GL Class, 2012 New York Auto Show

In April, owners filed another lawsuit against Mercedes alleging further testing revealed significantly higher emissions in dyno and road tests.

Mercedes has denied that the engine uses a "defeat device" to pass emission tests similar to Volkswagen, which admitted its 3.0-liter diesel engines uses an illegal "temperature conditioning" mode that was timed to the EPA's test cycle.

"We consider this class action lawsuit to be unfounded. Our position remains unchanged: A component that inadmissibly reduces emissions is not used in Mercedes-Benz vehicles," Daimler told Reuters.

Cotter didn't comment on whether the GLS350d's delay from the EPA was related to the pending lawsuits.

2013 Mercedes-Benz GL Class

2013 Mercedes-Benz GL Class

The EPA has not commented on the GLS350d's application for certification or if the automaker has submitted test data.

The automaker's website currently lists the GLS350d as "Coming Soon."

According to Mercedes, the 3.0-liter turbodiesel V-6 for 2017 produces 15 more horsepower and is mated to a 9-speed automatic transmission. In 2016, the GL350d had a 7-speed automatic.

Last year, the EPA rated a GLE350d with a similar 3.0-liter turbodiesel V-6 that was never made available in the U.S.


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