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Old 11-10-2008, 05:42 PM   #1
OrangeCrush1970
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Brake issues, thoughts please.

I had some brake work done about 6 months ago including a new master calendar and new brake calendars all the way around (drum brakes). Everything has been working well up until a week or 2 ago when I had to stand on the brakes...they felt mushy and the ‘brake light’ popped on. I checked my brake fluid but it was perfect. I see new pads all the way around in the near future, but aside from needing new pads what could be causing the brake light and mushy brakes?
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Old 11-10-2008, 05:51 PM   #2
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Re: Brake issues, thoughts please.

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Originally Posted by OrangeCrush1970 View Post
I had some brake work done about 6 months ago including a new master calendar and new brake calendars all the way around (drum brakes). Everything has been working well up until a week or 2 ago when I had to stand on the brakes...they felt mushy and the ‘brake light’ popped on. I checked my brake fluid but it was perfect. I see new pads all the way around in the near future, but aside from needing new pads what could be causing the brake light and mushy brakes?
I have some of questions:

What do you mean by "stand on the brakes?" Did the pedal all of a sudden become hard to depress or did the truck not stop when you depressed the pedal?

Did you install power brakes or are they manual?

First thing comes to mind is master cylinder defective.
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Old 11-10-2008, 05:58 PM   #3
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Re: Brake issues, thoughts please.

old rubber brake hoses will cause mushy brakes
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Old 11-10-2008, 06:08 PM   #4
OrangeCrush1970
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Re: Brake issues, thoughts please.

68gmsee, to answer your questions (1) I had to slam on the brakes when someone pulled out in front of me. The brake pedal was soft and the truck wasnt stopping, the wheels didnt even begin to lock up. (2) I have power brakes.

b-rad, I'll have to check out my brake hoses but they are 3 yrs old at the most.
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Old 11-10-2008, 06:58 PM   #5
68gmsee
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Re: Brake issues, thoughts please.

Sure sounds like a defective master cylinder. I had a similar problem on another vehicle. Brakes all of a sudden went spongy on me and had to pump it to stop. It was a master cylinder that was only a few months old.
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Old 11-10-2008, 07:25 PM   #6
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Re: Brake issues, thoughts please.

i'd try bleeding the brakes following the instructionsin the servicemanual about centering the combination valve// it's a common occurance no one has the service manuals for these old vehicles and its not at all uncommon to "pay a pro" and get highschool dropout service
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Old 12-29-2008, 01:19 PM   #7
OrangeCrush1970
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Re: Brake issues, thoughts please.

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i'd try bleeding the brakes following the instructionsin the servicemanual about centering the combination valve// it's a common occurance no one has the service manuals for these old vehicles and its not at all uncommon to "pay a pro" and get highschool dropout service

The brakes are getting worse so I need to address this soon...I have a haynes manual, but no service manual. I don't think that I have a combination valve...at least not an adjustable one.
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