If you are trying to pay GMAC mortgage -

I found this on a GMAC website (I found it by typing the following words into the Yahoo search engine (moneygram code gmac payment)):

"Moneygram
GMAC Mortgage also accepts MoneyGram. The fee for using MoneyGram is $8.50 for transactions up to $10,000.00. The fee for using MoneyGram at Wal-Mart locations is $8.50 with a transaction maximum of $1,900.00. Please remember to include your GMAC Mortgage account number and the receiver code - 2365. The payment cut-off time is 3:00 p.m. Central time. To locate a MoneyGram office near you call 1.800.926.9400 or go to www.moneygram.com."

Here's the link.

http://www.gmacmortgage.com/jump_pages/payment_options.html