Troubled companies usually have troubled pensions, if they have pensions at all. Bankrupt giants such as General Motors Co., American Airlines Inc. and LTV Steel were hampered by billions in unfunded pension liabilities. Then there’s J.C. Penney, whose financial problems have made headlines for months. The Plano-based retailer has one of the best-funded pensions in the country, thanks to management doing the right thing and doing it well.