In my 94 Ford Ranger 4.0 v6 when you go to push the brakes in it sounds like you have air or something goin on inside of it. What could this possibly be? What should I look for to fix the problem?

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I have a 94 Ford Ranger Super cab! That has a 4.0 V6 and an automatic transmission. The truck is now black with a silver/chrome front end, bumper, and fender flares. It has a 4 inch suspension lift with Rancho Shocks.

Could be the brake booster making the noise

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1999 Ranger 4.0 and extreme Snap-on tool fetish