’01 Kia Grinding Noise

I have a 2001 Kia Sportage. About 100,000 miles. It just started making a grinding sound when I take my foot off of the gas pedal. It makes this sound even if I do not touch the brake pedal. When I do start braking it will continue this grinding sound until I am almost stopped then will make a loud “thud” and stop grinding. I had my brakes done about 3 months ago and had the transfer case replaced 2 months ago.