Used auto loan rates are applicable if you are purchasing a used or secondhand vehicle. The principle amounts that you will need on these loans will be lower than new cars because of the fact that you are typically going to spend much less amount on a used auto than you would on a new auto. For these reasons, and with all other things equal (credit, etc), it is often more affordable to get a used auto loan, but you first need to qualify.
The normal conditions apply in calculating used auto loan rates. The bankers will try to delve into your credit history and current job and earning power to make sure that you will be able to afford the loan. They will try to find out if you have any other loan that you are making payments for, etc. They will also try and make sure that the vehicle you are planning to purchase is really a good buy.
Appraisal of the vehicle becomes more important in the case of secondhand vehicles because the finance providers need to find out that the vehicles will work for you at least for the life of the used auto loan. The last thing that a lender wants is a car that no longer runs, that still has some money due on the loan. They might also insist that you buy insurance for the auto from one of their affiliates. All these points are going to increase the payments that you make on your used car loans, but the one point where you will be saving is on the used auto loan rates.