I have a 96 ram 2500 12v, the light for the cruise control comes on, however it doesn't actually do anything when I try to set the speed.

I am thinking it might be a problem with the vacuum system in the truck, I am also having some problems with the brakes due to the vacuum.

Anyone have thoughts or suggestions?

 

Look at the vacuum line on the passenger side going into the firewall by the AC accumulator. This hose tends to fall on the turbo and then gets burnt in two. It is a common problem. If that is not the problem you will have to check all your vacuum lines. I use a hand vacuum pump for testing.

 

Okay thank you, I will check it out in the morning.

I am having another problem, in parking lots, stop and go traffic or if I use the brakes often. It suddenly becomes very hard to push the brake pedal down. We changed out the Brake Booster and the master cylinder was fine.

Would this line failure cause that same problem?

 

Yes. What is happening in stop and go traffic is that you are using the vacuum up and the pump cannot keep up with the demand. You either have a vacuum leak or a bad vacuum pump.

Do this test, before engine start, pump your brakes until the vacuum is gone. The brake pedal will get hard. Now start the engine and pump the pedal. You will feel it getting soft and back to normal as the vacuum builds.

You can follow the vacuum lines and look for cracks or openings. A vacuum pump may be the best and fastests way to find the problem. You can isolate the various accessories, brakes, cruise, HVAC, and test then individually.

 

2500 ram cruise issue. the system light comes on when set BUT the controll will not engage. I assume there is a fuse somwhere but I cannot find it..

 

early second gens don't have a hydroboost?

 

You need to fill out your truck info or state what year truck you have when asking a question. There are several generations of these trucks and have different systems.

The most common failure of the CC is a cracked or separated vacuum line that connects to the CC servo. The servo sits just beneath the drivers side battery. Battery acid works its way to the servo and vacuum line. The line then breaks or cracks. The servo itself could fail due to excessive battery acid. That was my case. I had a hole in my servo. I replaced with new.

Early second generation models use vacuum boost brakes so a vacuum problem could affect the brakes. In 97 or 98 they went to hydro boost brakes.

The servo and fender needs to be checked for battery acid. I painted my area with aircraft battery acid proof paint. See here.