I was driving my '88 IROC this evening and when I was going down a very steep road and put on my brakes, the front end started shaking real bad. The brake pedal was pulsing. It did this until I applied hard pressure, but only under braking. This road was a couple of miles long, and it did it repeatedly, and really scared me. After I got back on a more level surface, the brakes worked fine. I have never noticed this happening before, and was wondering if anyone had an idea what I should be looking for. I bought the car in June and have put about 6K on it without any trouble.

 

sounds like you found your first brake fade .. here in GA ..with all the hills .. you'd get it ALL the time :\ ... especially with a heavy
right foot ... new rotors , better pads , bleed the system ,
etc etc .... spohn will have the 1LE setup in a couple of months

 

Might be warped rotors, mine shudders when I brake all the time, drives me crazy .

 

Definately not brake fade. The brakes were still slowing the car just fine. I live in a mountainous area, but the grade I was on was 14% which is very, very steep.

I thought about warped rotors, but I've had them before, and could feel them whenever I braked. Not just on a downhill grade. The car hasn't done it today.

The car was shaking so bad last night that I thought I might lose control, or lose a wheel (which I checked, and they are nice and tight).

 

Check your idler arm and tie rod ends.If they are worn they will make the car shutter when braking with the heavy load of going down a hill.

 

I was hoping that wouldn't be it. If it is, any idea how likely is a connection will break once that starts to happen?

 

I would definetly check your Idler Arm. They are not the greates design and are subject to lots of torque loading especially when braking. It is easy to check. Crawl under the front end and locat the long drag link that spans the front end and is connect to the tie rods that are connected to you wheels. On the passenger side you will see about a six inch link that connects this draglink to the frame. Pull down on the drag link near where this link is connected. Don't be afraid to give it a good tug either because you are not going to do anything to it that a 3500 Lb car hasn't already done. If you see excessive play in that six inch link it is bad. That link is your idler arm and it is simple to replace. Hope this helps