Riding along minding my own business this weekend in my 85 300TD when I smell the unmistakeable odor of burning brake pads at a stop light. Pull over and check out passenger rear wheel stinks bad and is warm to the touch but not hot per se. Drive away for a few miles and at the next stop light brake pedal feels way soft but pumps up and stops the car....After a couple more stops everything seemed to get back to normal. I pulled the wheel when I got home and found brake dust on the inside of the wheel as I expected but nothing else out of order, no leaks etc. I did a pad replacement on the rear about two weeks ago and have put 500 miles on the pads. For the life of me I can't put a dragging piston and a soft brake pedal together anybody have any ideas ?

If it was dragging bad enough, and the heat was high enough, you could have boiled some of the brake fluid in the area of the caliper resulting in no braking action for that caliper.

There should have been some pulling away from that wheel, however. But, if that caliper was still dragging badly, you may not have realized it.

The fact that it returned to normal, on it's own, tends to favor this conclusion.

i had the soft pedal the other day...i just replaced my pads (in november) and one of the pistons got stuck..i took it to my mechanic's shop and he free'd it up with a hydraulic wedge....now when i was driving to his shop to get my alt repalced the pedal was almost nonexistant...we quickly discovered that the caliper was leaking and need to be replaced....


kris

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Thank you Brian and Kris. Never heard of boiling brake fluid, it did stink but didnt feel that hot but a bundt wheel is a good sized mass to heat up, no evidence of leaking on very close inspection under strong light. The boiling does make sense when I pumped the pedal it collapsed the void and then things seemed normal again. I guess I will just have to watch it closely.

Yes it can. Just as Brian said you can get the moisture in the brake fluid to boil and give you a "softy" Pull the wheel off and give a quick check.

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