breaks o fading

[1974 Wagoneer]

When I step on the brakes I get initial pedal then it slowly drops to the floor. One pump solves the problem.

I will be looking at the master cylinder and the wheel cylinders.

Where should I start and what else might I need to look at.

[johnypreflt]

My truck does similar and I am pretty sure it is the rear wheel cylinders leaking. saw a little fluid when I pulled the drums a few months ago but havent had time or oppertunity to fix it.

[gsmikie]

sinking pedal ====master cyl

[rough_idle]

Master cylinder. Had the same problem for months. Then pumping wouldn't work and the brakes barely gripped with the pedal to the floor. Took it in and had had the M C replaced. Perfect now.

[Al Johnson]

If you are losing fluid, it's a line or a wheel cylinder/caliper. If you are not losing fluid, it's the master cylinder. From your description, I vote for master cylinder, but as long as you're working on the brakes, check all the possibilities.

[1974 Wagoneer]

Thanks guys. Started with the master cylinder and solved the problem. On to the wheel cylinders as I replace break pads