Revolving util is scored much differently than installment util. If you had $1000 in total CLs on various cards and paid your balances down to $200, then your available credit is $800 with a utilization of 20%.
Unlike revolving credit, installment is different. If you have a $1000 original balance on a car loan, and pay it down to $200, your installment util is 20%, but you don't have $800 in available credit like a CC because you can't get that credit back without opening a new loan. Make sense? Therefore, installment utilization is hardly scored at all. You're not going to get pegged by opening a new loan at 100% utilization. If you opened a $400k mortgage on a new home, it'll take years to go below 90% of the org. loan amount and that's why FICO won't ding you the same like a CC.
In your example, paying a loan down to $1500 won't do anything per FICO. Now if you have the means to do that, then certainly do so. You'll save hundreds of dollars (depending on the APR) and improve your cash flow much, much sooner vs. paying the loan as scheduled.
