I got in my truck this after noon and the the brake pedal was hard as a rock!
I almost went through a busy Intersection. What might be the cause here?

 

Dodge has a real sensitive anti-lock circuit for the rear brakes. If it gets any water in the fluid, it can cause the combination valve to lock up and keep the pedal from depressing. Get a helper, and have them depress the brakes with the engine running, and you put you finger on the front nipple of the combination valve (just down below and beside the master cylinder - you cannot miss the thing), and feel for the plunger to be working with the pedal. If it is not, you need the brake system serviced. As preventive maintenance, the brake fluid should be flushed at least every two years to keep disolved water out of the system.

The next most common problem is a failure of the vacuum pump or the vacuum booster on the brake. Check that like any other vacuum brake system. Start the engine, let it run a minute, then shut it off and immediately depress the brake pedal with your hand and listen carefully for the vacuum valves doing their thing. If you cannot easily depress the pedal with your hand, then check the vacuum pump to be sure it is generating adequate vacuum.

Lastly, there are still a few people that install new front brake pads and do not replace the calipers. If that has happened the front calipers will bind and the system can freeze. The OEM Dodge calipers are absolutely notorious for wallowing out the bores where the cups and pucks reside. Once those bores are no longer straight and true, you can get all sorts of braking problems.

 

Sounds like loss of vacuum.

 

I recently had a similar expeirance where a vacume line rubbed through. Might wanna check the system first, at idle 20 inches was said to be a good number. If its low start trackin lines. the one to the cruise control on mine was bad. Check the line to the brake booster connections and the pump line out. these things are easy and free and a good place to start.

 

It was a loss of vacuum.
I had been messing around under the hood earlier and somehow unplugged the vacuum line to the brakes.
I fugured it out right after posting thread.
Thanks guys!