I have a 95 Chevy c1500 5.7 when I hit the brakes it sounds like you are sitting the brakes on a 18 wheeler
If you have disc brakes, look at the rotors and feel them. Are they smooth or have ridges in them. Can you see the pads? Are they worn? If so, you need a brake job. If it is drum brakes, you will have to pull the wheel and the drum off to look to see if there is any excessive wear on the drums or pads. If you just had the brakes done, it may be the pads are making the noise. The pads can be changed out for more expensive ones that don't "Squeal" if that is what you mean. It should not cost you anything to have them checked. Always get two or more estimates on any fix or repairs.
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