GM Proportioning Valve Reset

Here’s why your old Chevy’s brakes won’t bleed. Skip to 3:38 for step-by-step instructions.

Reset my proportioning valve after the rear drums weren’t getting any fluid following a master cylinder change.

WARNING: I’m pretty sure brake fluid is highly corrosive and can ruin paint. Consider wrapping rags around the bleeder screws before opening them at pressure. Also don’t drink brake fluid.

[abdul-kabiralegbe]

This is THE BEST explanation of this component and how to reset it I've found on YouTube. Thank you!

[StevenCrowtown]

I have the same style proportioning valve in my 1972 pontiac catalina. I'm about to replace all the brake components, so knowing this will help in getting the system functional.

[livenfree]

To reset with the side buttons, remove the rubber cap. Grab a 3-in nail between some small vice grips and push in on the center or try the Allen wrench like he showed. Mine only moved an eighth of an inch and I didn't think it did anything but it was enough. The light was off. You'll know when you're brake light turns off and the key is on for a minute. Back brakes bled fine after. Push from the front to release the back push from the back to release the front.

[mehdirezaie]

thank you for the awesome video. I was losing my mind. I am having a similar issue. Replaced all brake lines, hoses, calipers and wheel cylinders. Let the system gravity bleed (before I do manual bleeding) but I did not get any fluid in the rear (neither driver side nor passenger side). Bled the master cylinder but still did not help. Then, found this video.

[timabernathy]

Great information I was starting to cuss after replacing the master cylinder this got me back on the road in minutes .. thanks

[MultiPeanut]

Thanks for the video, I installed rear disc on back changed porpotioning valve also.

[VainCharisma]

Thanks man I have a 87 k5 and had the same problem replaced the master cylinder lines and the whole brake assembly on front and back tried this and its a good a hold now! Thanks, and subscribed.

[marcellaluke]

So I had everything replaced on my 88 Chevy Silverado Suburban breaking system. My front brake started squeaking 6 months previous. The fill on the master cylinder stays full but the other side goes dry so I end up filling it with brake fluid. What can I do to get this resolved as it seems there is a problem with the master cylinder?

[ari.]

C10 1986 rear brake line broke.. The shop fixed it and bleed the brakes.. but the light still on..They told me to replace the whole valve. Not sure

[littlebigplumbing]

Holy shit..Thank you for this! My fucking brain hurts tying to sort this out

[vezina]

So basically you started bleeding your front brakes first then the rears?

[terencebarela]

I have a 98 Tahoe 5.7 engine with police package break system, can’t find my proportioning valve any help?

[enriquegomez]

Hey bro my brake pedal on my c10 is stuck it won’t go down, happened while bleeding brakes and front caliper replacement…. Any idea what it could be???

[Larry-di]

My front brake line broke, and the switch did not kick over and block the fluid from shooting out. The vehicle is a '92 Dodge truck and the valve is no longer available. GM PV2 is supposed to work but has anybody tried it on a Dodge? I feel sure it would work, but only if the fittings and electrical connector would mate up to the lines and wire.

[theundefinedprogamer]

I got a 83 k20 scottsdale and just replaced drums and brake lines I have brake fluid coming out of the rear and fronts I have a solid petal until I start the truck once it’s running I have no pedal at all do you think this is a similar issue or another issue? A brake line cracked but before that brakes worked fine

[johnnyturbo]

Once you do that how do you know it's reset? Does the "brake light" on the dash go out and once that happens you bleed them normally?

[josephj]

I wonder if this would work for my Honda civic

[manhalaridi]

Hi there, I changed the valve and still get this issue: the rear brakes stop before causing the the wheels to slide, mainly the rear right one. Any idea?

[SOU]

I've heard there's a special tool of some sort that you put on the proportioning valve to keep it from locking out the brakes when you bleed the system. I I'll probably have this issue with my 85 C30 when I rip the drums off to replace the wheel cylinders as well as bypass the hight sensing proportioning valve on the rear for the back brakes. Hopefully I won't have to bench bleed the master cylinder because the reservoir for the back brakes is bone dry because the rear brakes loose so much fluid.

[illuminancecrt]

Hi Kyle, thank you for this video. My 93 S10 is in the situation since I changed the front brake hoses/calipers/discs. Now it won't bleed. If I now open the rear brakes and apply pressure, why won't the valve just go all the way over to the other side and block off the rear lines at that point? Why would the valve reset? Seems like I would solve one problem, and create a new one? What am I missing?

Thank you!