Author Topic: front brake problems  (Read 2847 times)

Offline doctrdoo

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front brake problems
« on: September 13, 2006, 02:24:00 PM »
i have an 85 C10,2wd longbed pickup.here's my problem-when i step on the brakes -the front brakes seem to lockup. i've already bleed the brakes 3 times,replaced the front callipers(because one of the bleed valves broke off while bleeding brakes),put on new pads(while i had it apart) and flushed out all the old fluid and replaced with new fluid.it seems to do it the worst when i first start to pull out of driveway(such as around 5-10 mph but not as bad after i run it higher(like around 30 mph.i'm not loosing any fluid and around the wheels are dry.could this be a vacumn issue since the brakes are vacumn assisted and there is a check valve in the vacumn line(from manifold to brake booster)? this has got me perplexed and it's a little un nerving at times.thanks


Offline VileZambonie

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Re: front brake problems
« Reply #1 on: September 13, 2006, 04:52:00 PM »
Are you sure the fronts are locking up? Jack up the front end and see if they apply and release easily when you spin the wheels. If everything is ok replace the combination valve.

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Offline VileZambonie

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Re: front brake problems
« Reply #2 on: September 13, 2006, 04:53:00 PM »
Also check to make sure the front hoses aren't twited around like a twizler as in if someone flipped the caliper when doing a brake job.

,                           ___ 
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              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10

Offline doctrdoo

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Re: front brake problems
« Reply #3 on: September 21, 2006, 05:38:00 PM »
I'm positive that the front brakes are locking up-i can hear it and feel it when i apply the brakes.I also have checked the front hoses and they aren't twisted and they are on correctly.What is a combination valve and where is it located at?The only parts that i haven't replaced so far (that i can tell) is the brake fluid resevoir and the brke booster.thanks for the help.


Offline VileZambonie

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Re: front brake problems
« Reply #4 on: September 21, 2006, 07:40:00 PM »
Follow the lines down from the master cylinder in the front crossmember area and you will see the combination valve.

,                           ___ 
                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10