This is my first post so please forgive any mistakes or reposts.

I have an F-150 2WD with a straight 6 cyl. 160,000 miles. I have two problems with my brakes.

1. Pedal feel is very spongy and the pedal point at which the brakes take effect is low. No loss of fluid. Is this a sign of a failed vacuum booster or master cylinder? The brakes have always made a weasing/air noise inside the cabin when pressing the pedal (leading me to believe that the low pedal problem was the booster). Now there is no noise.

2. Recently I experienced erratic steering behavior on a short drive thru town. To make a long story short, it looks as if my right front caliper is frozen (continuous braking force being applied), seems like a stuck cylinder piston (?).

Are these two problems related? Is it worth it to rebuild the brakes (caliper and/or master cylinder) or purchase new? How are rebuilt parts for Ford vs. OEM? Any brands you suggest?

I purchased the truck with 140,000 miles on the odo, so I don't know what type of work has already been done brake wise.

Any advice welcome. Thanks

 

You must first check the rear brake adjustment. Low pedal could be caused by misadjusted drum brakes. You want a slight drag on the rear wheels when turned. You could have a bad front caliper. If so, replace both of them. I would also replace the rear wheel cylinders if you do not know their history. Check all the hoses also. If they are cracked, replace them. As for parts, aftermarket from Advance or Auto Zone are fine as long as you buy the lifetime warrantied pieces. Try the rear brake adjust and let us know how the pedal feels now. You may just want to replace the master cylinder as well. The hissing noise you hear is the brake booster. Does the engine idle funny when you press the brake? If so, the booster may be leaking vacuum. Hope this helps.

Robbie

 

Thanks Robbie:

Great tips. I'll ready over the manual to see what the steps are for adjusting the rears. My hunch is that it's the master cylinder, but I wanted to survey you all to see if I was correct. I'm not losing fluid so the seals might be bad. I was thinking it also could be the booster since the wheezing noise didn't sound right with a constant sound of air rather than the momentary whoosh one typically experiences with american vehicles.

So suggest replacing both calipers at the same time eh? Perhaps better to get more balanced braking. I just ordered a new Ford (remanuf.) right caliper but may get the other under your advice.

I suspect my problems are numerous since the fluid looks pretty black and probably has a lot of H20 in it (causing the seized caliper piston).

I'd rather attack this one part at a time due to the cost. Perhaps I'll follow your sequence of remedies: caliper, rear brake adjust, then master cylinder, and if need, the booster. I can get a master cyl/booster combo for about $160 so I might do them together.

Thanks again for the input. Seems like you've been here before.

cheers!

 

A bad or leaking vacuum booster will cause a high/hard brake pedal. If a front caliper is stuck you might as well do both. The calipers for my f-150 were like $15 a piece.

-Jon