start by checking wheel bearings. not enough info for a good diag.
might be the brake pad
The grinding sound means that the brake pads are worn down to metal and that sound you hear is metal to metal. you need to have the pads changed, the problem is that you will more than likely have to change the rotors also. The way to avoid this in the future is when you notice your brakes are making a squealing sound that means that the pads will need to be changed soon.
A bad transmission. The sound is from metal grinding on eachother.
That is the sound of metal on metal. I suggest you immediately take your car to a mechanic and have the brake pads replaced before you cause too much damage to the discs.
brake shoes or pads are worn and need replacing
If the car is making a squeaking sound or sounds like metal grinding, it is likely that you have a brake pad or brake rotor issue. If this is the case, you need to take it in very soon.
it could be a number of things but it depends i dont know what it sounds like but it could be your break or cb halfshaft Brake pads worn out. Metal to metal contact. Inspect brake pads, asap.
Brake shoes worn out. Replace them and have the drumns resurfaced.
The brake pads are worn out and need to be replaced. The grinding sound means your brakes are about to stop working.
Is it accompanied by a shuddering or vibration? You could likely have bad brake rotors.
Are you Breaking when you get the grinding sound? Or attempting to switch to 4 wheel? Most common grinding sound I know is a worn out brake pad tearing up a rotor. Time for a brake job. New rotors and quality pads can be had for about 150 if you do the labor yourself.
Check if muffler is loose, check if rear brakes are worn out & grinding