break proportion valve bad

10

Asked by Mar 05, 2016 at 06:00 PM about the GMC Sierra 1500

Question type: Maintenance & Repair

when I step on my brakes the brake calipers
lock up in the front, really bad the first time
and won't release, I completely flush the
system several times with brand new dot3
brake fluid, I replaced both calipers on the
front, no luck, I replace both rubber brake
lines in the front, no luck, I completely
rebuilt the break master cylinder, still
locking up, when I open the proportioning
valve while the calipers are locked up they
release, is my proportioning valve bad? and
what are everyone's thoughts on getting
one from a junkyard I've heard bad news?

2 Answers

78,585

You didn't state what year, but wrecking yard valves tend to have problems, have you checked for an aftermarket valve?

10

1991. brand new ones are about $110 plus the shipping each, I'm taking apart the proportion valve now, can't seem to loosen the threads to the back brakes, it's a SOB, I had some rust bolt loosening oil which I squeezed on it, I took the front and rear springs out of the proportioning valve but if you look into the middle where the brake light sensor is if it grounds, it looks all black and gooey I'm trying to get everything out and then clean it put it back together.

Your Answer

Add photo

Related Questions

Search GMC Sierra 1500 Questions

GMC Sierra 1500 Experts

#1 dragonflyoffshore
dragonflyoffshore
Reputation 4,500
#2 John Saffrahn
John Saffrahn
Reputation 3,150
#3 Glenn Clingenpeel
Glenn Clingenpeel
Reputation 2,780
View All

Related Models For Sale

Used Chevrolet Silverado 1500
2,729 Great Deals out of 150,184 listings starting at $1,259
Used Ford F-150
3,433 Great Deals out of 208,025 listings starting at $1,273
Used GMC Sierra 2500HD
140 Great Deals out of 13,561 listings starting at $1,500
Used Dodge Ram 1500
536 Great Deals out of 13,008 listings starting at $1,200
Used Toyota Tundra
709 Great Deals out of 28,881 listings starting at $2,500
Used Chevrolet Silverado 2500HD
375 Great Deals out of 28,619 listings starting at $2,295
Used Ram 1500
1,424 Great Deals out of 117,298 listings starting at $6,999
Used Toyota Tacoma
773 Great Deals out of 34,326 listings starting at $2,988
Used GMC Yukon
557 Great Deals out of 17,631 listings starting at $1,777
Used Chevrolet Tahoe
1,073 Great Deals out of 31,900 listings starting at $1,700
Used Ford F-250 Super Duty
455 Great Deals out of 43,210 listings starting at $2,850
Used GMC Sierra 1500HD
8 Great Deals out of 120 listings starting at $4,988
Used Chevrolet Camaro
640 Great Deals out of 39,733 listings starting at $2,995
Used GMC Canyon
151 Great Deals out of 8,243 listings starting at $2,995
Used GMC Sierra 2500
190 listings starting at $5,995