The 2001 Dodge Ram was the last production year for the redesigned Ram model line that first appeared in 1994. The sleek and muscular styling exuded the power of a big rig, while still remaining sporty and sleek. From 1994 through 2001, Dodge continually improved on the design, with the 2001 model year seeing a significant improvement in the braking systems of the 2500 sub-model. Antilock braking became standard, as did dual piston calipers on the front disc brakes. The large brake booster remained at the heart of the system. Ram owners can easily learn to troubleshoot the power brake booster operation themselves by performing a few simple tests.
Park the Ram on a level surface and let the engine idle. Hold down the brake pedal with a steady, light pressure and turn the engine off. Keep holding the brake pedal down for a minute or so, and pay close attention to any change in the position of the brake pedal. If you feel the pedal rising slowly and slightly, it means that the brake power booster is not holding vacuum (air is leaking into the booster).
Pump the brake pedal half a dozen times to relieve any vacuum still remaining in the booster. Once again, push the brake pedal down and hold it there with steady, light pressure. Start the engine, and pay careful attention the position and feel of the brake pedal. The brake pedal should drop about 1/4 inch as soon as the engine starts, and the pedal feel should change from a hard feel to a slightly softer feel. If this does not happen, it can mean that the booster is leaking and cannot hold vacuum, or it can mean that the vacuum from the engine intake manifold is not being properly transmitted to the booster.
Let the engine idle for a few minutes to allow the vacuum to stabilize in the booster. Do not touch the brake pedal during this time. Turn the engine off and immediately pump the brake pedal once. Pay careful attention to where the brake pedal stops. Pump the brake pedal a few more times, waiting one or two seconds between each pump. Each time pay careful attention to where the brake pedal stops. If the booster is functioning properly, the brake pedal should stop at a slightly higher position with each pump. If the booster is not holding a vacuum, then the pedal will stop at a high position on the first or second pump, and will stop at the same high position with each following pump.
Park the truck and open the hood. Locate the brake power booster. It is a round, semi-dome shaped component located on the driver's side of the engine compartment, mounted to the rear wall in line with the brake pedal inside. There is a black rubber hose connecting the booster to the engine intake manifold. Trace the rubber hose back from the booster to the intake manifold connection and disconnect the hose. This is done by using pliers to remove the retaining clip and then pulling/wiggling the hose off the connection nipple. Now try to blow air into the hose. If the booster check valve is functioning properly you should not be able to blow air into the booster. Next, try to suck air out of the booster. If the booster check valve is working properly you should be able to suck a small amount of air out of the booster. If you don't want to get your lips dirty, you can wrap the end of the hose with saran wrap, or you can use the bulb from a meat baster instead of your lips.
Connect a brake vacuum test gauge to the nipple on the engine intake manifold. Start the engine and let it idle for a minute or so. The vacuum gauge should read 18 to 20 inches of vacuum. If it is less, then your engine needs a tune-up. If you do not have a vacuum test gauge, then start the engine and place your finger over the connection nipple. The vacuum should feel firm and strong.
