Reading about the woes of Ford and General Motors these days, you could easily assume that the American automotive industry is in a state of deep despair. Sales are off; debt ratings are cut to junk or near-junk status; quality is suffering. Yet that's nothing compared to the wretchedness that defines the auto parts supplier industry.

Once again, an auto supplier has filed for bankruptcy protection. Collins & Aikman, one of the top 15 auto suppliers in North America and a company that provides flooring, fabric, and instrument panels to car manufacturers, filed for Chapter 11 protection on Tuesday as it suffers the fallout of high costs and tough competition. It follows the bankruptcy filings of smaller competitors TowerAutomotive, Intermet, Citation, and Meridian Automotive Systems.

Collins & Aikman's website says that the company's parts appear in 90% of all vehicles sold in North America. Yet as the cost of steel, resin, and oil have grown, the automakers have sought to save money by squeezing their suppliers. Ford and DaimlerChrysler have said they will cooperate with the company, while banking giant JP Morgan has agreed to extend up to $300 million in debtor-in-possession financing to the parts supplier to avoid any disruptions to the industry.

The problems at the bottom of the auto-supplier base have turned investors' attention to the top of the food chain as well. Delphi (NYSE:DPH) and Visteon (NYSE:VC), though somewhat more financially secure because of their relationships with General Motors and Ford, are under the gun because of high pension and health-care costs, as well as the soaring costs of raw materials.

Delphi, a GM spinoff, is the country's largest parts maker, with nearly $29 billion in sales and a market cap of about $2.3 billion. Visteon, the former Ford components supplier, has about $19 billion in annual revenues and a market cap of around $700 million. Both companies recently announced that they would delay filing first-quarter financial statements with the Securities and Exchange Commission because of accounting problems. (Delphi previously projected a $200 million loss for the year.)

Delphi and Visteon suffer from their former parents' reported slack sales and resulting production cutbacks. Both have also been the recent target of credit-rating cuts by Standard & Poor's and Fitch Ratings.

Should Delphi or Visteon (or both) file for bankruptcy protection, the Big Two automakers could see serious repercussions. Ford has already filed a statement with the SEC stating that a "significant charge to earnings" could occur if Visteon pursues a restructuring. Delphi has denied that it will seek such protection -- but so did Collins & Aikman, and so do most companies just before filing for bankruptcy -- though it has hired restructuring advisers Rothschild to help it untangle its financial woes.

Those results contrast sharply with others in the parts-supply chain. Motley Fool Stock Advisor selection BorgWarner (NYSE:BWA) has reported stellar results, while Johnson Controls (NYSE:JCI) and Parker Hannifin (NYSE:PH) have also reported stronger sales and profits. These companies are not beholden to the automakers or are more diversified in whom they represent. BorgWarner, for example, supplies drivetrains to both American and Asian car manufacturers. Parker Hannifin sells motion and control technologies and systems to automakers, but also to the oil and gas, mining, and construction industries, which have been seeing boom times.

These are not heady days in the auto-parts industry, to be sure. Yet investors, particularly value investors, may want to keep a close eye on things. Great opportunities can arise from dark days like these. Delphi and Visteon are both sitting at their lowest levels ever, some 70% or more off their 52-week highs. It's way too early to move in yet -- buying too soon can be just as disastrous financially as buying too late -- but if the smoke clears and stability starts to return, there could be a chance to reap big profits.

Right now, though, the industry represents more of a junkyard than a new-car lot.

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Motley Fool contributor Rich Duprey owns shares in Ford but does not own any of the other stocks mentioned in the article. The Fool has a disclosure policy.