Longer processing times for mortgages is driving down customer satisfaction rates, according to a J.D. Power and Associates survey released Thursday. The study found that as the origination processing times increased in 2010, up to 52.1 days from 46.9 days in 2009, customers became less satisfied with their banks. The customer satisfaction index decreased to 734 from 739 last year. The index is based on a 1,000-point scale with the higher reading meaning a higher level of satisfaction. Director of Financial Services at J.D. Power and Associates David Lo said that although processing times negatively influence a customer’s experience with bank, there are certain factors that make a positive impact on customers. He said the practices closely associated with high levels of satisfaction include providing proactive updates on the status of a loan, providing a welcome acknowledgment after an application is submitted, and closing on the promised date. Quicken Loans ranked first in the customer satisfaction survey with an index of 826, followed by MetLife Home Loans (MET) (808), PNC/National City Mortgage (776), U.S. Bank (USB) (775) and SunTrust Mortgage (STI) (770). Wells Fargo (WF) ranked eighth at an index of 758, while the other three Big Banks rounded out the bottom, strengthening the correlation between processing times and customer satisfaction. The Big Four banks account for 32.1% of all active mortgage loans. Chase‘s (JPM) index was 699, CitiMortgage/Citibank‘s (C) index was 691 and Bank of America‘s (BAC) was 676. The 2010 U.S. Primary Mortgage Origination Satisfaction Study is based on responses from 3,401 consumers who originated new mortgages. The study was fielded between July and August 2010. Write to Christine Ricciardi.