Ford Motor Co. is selling a portion of its share in Mazda Motor Corp. as part of a plan to bolster its balance sheet in the midst of a slumping economy and industry-wide slowdown.

The U.S. auto maker says it is cutting its stake in the Japanese car company from 33.4% to just over 13%, a move that will net Ford about $540 million.

The shares will be sold to Mazda and a group of its “strategic business partners,” Ford says, noting the sale should be finalized tomorrow.

“This agreement allows Ford to raise capital that will help fund our product-led transformation and at the same time allows Ford and Mazda to continue our successful strategic relationship in the best interest of both companies,” Ford CEO Alan Mulally says in a statement.

The two auto makers have partnered on numerous product programs over the course of their 30-year relationship. Mazda platforms currently underpin several Ford vehicles, while Ford assembles some Mazda products. The two also have joined on powertrain programs.

Mazda and Ford will evaluate future product collaborations “in terms of what is in the best interest of both companies,” says Ford spokesman Mark Truby.

Ford has been seeking to bolster its liquidity after reporting a third-quarter pre-tax loss of $2.7 billion. The auto maker’s stake in Mazda resulted in a $1 million loss for the quarter, compared with a $14 million profit year-ago.

Mulally and other leaders of the Detroit Three have been lobbying lawmakers in Washington for bridge loans to help the industry weather the current economic downturn. However, Truby says there is no connection between the Mazda sale and Ford’s talks in Washington.

Following the sale, Ford will remain Mazda’s largest shareholder and maintain a seat on its board of directors.

Meanwhile, Mazda says President, Chairman and CEO Hisakazu Imaki will relinquish his post. Imaki, who will remain chairman, will be succeeded by Takashi Yamanouchi, currently executive vice president. The personnel changes are effective Nov. 19.