Adds CEO and CFO comments in paragraphs 8,10

By Abhirup Roy

SAN FRANCISCO, Nov 5 (Reuters) - Lucid LCID.O lowered its 2025 production forecast to 18,000 vehicles, interim CEO Marc Winterhoff told Reuters on Wednesday, as the electric-vehicle maker, like many of its rivals, grapples with a slew of supply challenges and production constraints.

Shares of the company fell 3% in extended trading, after it also reported third-quarter revenue below analysts' estimates and a bigger-than-expected loss, despite a jump in deliveries sparked by the now-expired $7,500 tax credit on EV purchases.

Besides, Lucid said the Public Investment Fund, its largest shareholder, had agreed to increase a credit facility to about $2 billion from $750 million.

The facility remains undrawn, it said. But the money is crucial for the company, known for its Air luxury electric sedans, as it ramps up production of its recently launched Gravity SUVs and prepares to roll out a more affordable mid-size vehicle next year.

Apart from a hit from high tariffs imposed on auto part imports, Lucid, like some its rivals, has been combating a chip shortage, uncertain supplies of rare earths and a fire in September at an aluminum supplier.

That led to a slower-than-expected rise in production of the Gravity SUV and, to some extent, the Air. The company has resolved some of the supply constraints and added a second shift to bump up production, Winterhoff told Reuters last month.

Lucid had already lowered its 2025 production forecast in August to between 18,000 and 20,000 vehicles.

"We will end up at the lower end of that range," the interim CEO said on Wednesday, citing issues from chip shortage to the fire. "Even if we solve it, it doesn't mean that it's none."

Six analysts on average expect Lucid to produce 17,320 vehicles this year, according to Visible Alpha.

Lucid expects some relief from the Trump administration's 3.75% tariff offset for U.S.-made EVs, said Chief Financial Officer Taoufiq Boussaid. The impact of tariffs is expected to be 8%-10% on the gross margin value in 2025, down from 21% in the second quarter, he said.

For the quarter ended September, Lucid reported a 68% jump in revenue to $336.6 million, but well below analysts' average expectations of $379.1 million, according to data compiled by LSEG.

The company posted an adjusted loss of $2.65 per share, compared with the estimate of a $2.27 loss.

(Reporting by Abhirup Roy in San Francisco; Additional reporting by Chris Thomas and Akash Sriram; Editing by Shilpi Majumdar)

((abhirup.roy@thomsonreuters.com; +1 415 941 8665; @abhiruproy30;))