It's not going to HELP you any, but it WILL hurt your motor. The first # should be as LOW as possible to ensure proper protection on cold starting. Remember, the first # is for the weight of it when it is cold. The lower the #, the faster it can flow to your motor to help protect it. More than 50% of engine wear occurs on start-up.
Once the oil has warmed up, the higher # comes into account. You want a high one to coat the engine better, but the first # does not need to be high at all. 10W-30 will actually kill your motor sooner. Go to something really heavy like maybe 20W-50 if you need protection. Still, I think 5W-30 is a great weight for any Taurus motor.
2001 Taurus SES - 150,100 miles - The new child
1999 Mazda 626 - 156,100 Miles - Slow and steady