Since the financial collapse and ensuing stock market crash, we've witnessed one of the greatest bull markets in history. Look at the graph below displaying how the S&P 500 has soared since February 2009.

^SPX Chart

^SPX data by YCharts

Warren Buffet's quote, "Be fearful when others are greedy, and greedy when others are fearful", seems to fit our current situation quite well. With the market sitting near record highs it has some investors so nervous about a potential pullback that it's making them cautious to invest in the market – and that's understandable. But there are always values to be found, and profits to be had. Ford (NYSE:F) and General Motors (NYSE:GM) are two stocks that have a sustainable and profitable future, and could be two of the best stocks to invest in right now.

Market share
In the first quarter this year, Detroit's Big Three accomplished something that hadn't been done in 20 years – all three gained market share. "The renaissance in Detroit is real," AutoNation CEO Mike Jackson told AutoNews in a telephone interview. "They have fantastic new products, and they're in a very good position to compete."

The good news is that Ford's market share is expected to increase this May compared to last year, according to TrueCar. It forecasts Ford to improve its share in the U.S. from 15.5% to 17.2%, while GM is expected to stay flat at 18.5%. For GM, staying flat is better than losing share, as rival Toyota is forecast to drop from 15.3% to 14.9%.

Leaner operations
Ford's CEO Alan Mulally established his "One Ford" vision and it's paying off big-time. The company is producing more profits than GM, off lower revenue, because it's running so efficiently. The good news for GM is that it's potential isn't as tapped as Ford's right now. It expects to improve operations and significantly boost profits and margins by mid-decade.

Analysts estimate that Detroit automakers are running lean enough to break even or produce slim profits if the U.S. automotive market breaks 10 million units in sales. That's great news, as the previous break-even mark was 16 million units, and the SAAR is standing just above 15 million right now.

Future lineup
Lean operations are a huge reason for excitement with investors, but it gets better. Both companies are having success with new models. Consider that Ford can't make enough Fusions or Escapes to keep its inventories as high as it would like. Plants that produce the Fusion are said to be running at 114% capacity, making each sedan rolling off the line more profitable than the last. Ford is bringing extra capacity to plants next year and is shortening its standard summer shutdown in half. Ford gets it now, and will continue to produce vehicles that strike the right balance of design and value with consumers – a great sign for investors.

GM is a little behind Ford in releasing new vehicles because it needed to shore up its financials first. Finally it's able to dust off the oldest vehicle portfolio in the industry and plans to refresh, replace, or redesign almost 90% of its vehicles by 2016. I expect that to pay off for GM and improve its top and bottom lines drastically. GM also has a leg up on Ford when it comes to its luxury Cadillac line – which brings home higher profit margins than standard cars. Ford's working to turn its Lincoln line to compete in the luxury segment, but it has a lot of progress to make.

Bottom line
Ford and GM seem to have bright futures with their leaner operations and popular new models. Both look to gain market share and are taking full advantage of consumers hitting the showrooms. Investors are happy with improving profits, operations, market share, and vehicles, and the second quarter is shaping up to be just as profitable as the first. Ford and GM have a lot of momentum right now, and seem like two of the best stocks to invest in.

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Fool contributor Daniel Miller owns shares of Ford and General Motors. The Motley Fool recommends Ford and General Motors. The Motley Fool owns shares of Ford. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.