http://www.lowpaymentnow.com/mortgage-refinancing/

can you lower your Mortgage (without Refinancing) by having excess in escrow once taxes and insurance are paid?
My statement came in stating that I am under $15.00 in escrow for taxes to be paid in December. My mortgage payment went up by $3.00. Now while this is small, I was wondering if I had a surplus in escrow would the mortgage payment be adjusted to show that I pay less the following year because of the surplus?
Yes, it would. It doesn’t “lower your mortgage” – just your monthly payment because less has to go into the excrow account.
Upside-down Loan Mortgage Refinance Presentation – Principal Reduction