Here's an update. It was not the chassis fan that was running fast as I first suspected It was actually the power supply fan. System Diagnostics showed that one of the power supplies was throwing errors. I pulled the suspect power supply and re-ran the System Diagnostics. No errors. THe suspect power supply also will not power the server. I should have realized that obvious symptom before postuing this question. So, it turns out the whole problem is a bad power supply. Interesting side note. The green light on the bad PS is on. 
My T410 has 1 CPU and 2 power supplies. With only one power supply plugged into power, the chassis fan is quiet, but when I plug-in the second power supply, the chassis fan speeds up. Any ideas on what would cause this behavior? ThanksJerry 
T410 2nd Power Supply causing higher chassis fan speed