Braking issue

[Usareke]

Every time I put the brake pedal down my truck pulls to the right, hard. Has anyone else seen this before? I'm thinking proportionaing valve, but I'm not sure and don't wanna tear that out yet, I replaced the master cylinder, and I do know that my booster is a little worn out, but that doesn't seem to be the issue I wouldn't think. Any help is greatly appreciated!

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[bd]

Was the master cylinder replacement an attempt to correct the pull?  Was any other brake work performed? 

Rebleed the brakes.  Pay particular attention to the volume of fluid flowing out of the bleeder valves.  Most likely there is either air in one side or a caliper hose is collapsed internally.

[Usareke]

I had the system flushed and. I replaced all pads about 6 months ago but this is a new issue, my brake idiot light has came on though as well

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[Irish_Alley]

im with bd. if the truck immediately pulls to the right when you apply the brakes suspect the left hose. if it becomes restricted it will have less drag the the right side and the right side will slow down more (pulling to the right). ive had the metal brace on a brake hose rust and the rust will squeeze the hose. it would allow the pressure to slowly go past but not immediately, then when i would release the brakes the same side that was restricted would drag. once i lifted the front end up i could press the brakes then walk around to the left side and the tire would still be stuck.

[bd]

I had the system flushed and. I replaced all pads about 6 months ago but this is a new issue, my brake idiot light has came on though as well

If you unplug the tan wire from the combination valve does the warning light go out?

[Greybeard]

That was my thinking BD, the proportioning valve slid over causing the light to come on. Irish hit that problem on the head, too little pressure getting to the left brake is causing the proportioning valve to compensate to the right side illuminating the idiot light. (Edit to add- brain fart!)

Booster really would not come into play for this type problem.

Might just make certain the new brake replacement did not result in a sticking caliper due to forgotten grease, or possibly a bad pad that came loose from the backing plate. I had that happen recently on my car, the pad came loose and caused it to pull when braking.

[Usareke]

Thanks, I checked the pads a week ago, they were fine, I guess I'll go with new lines they are old and cracked, braided steel lines a good investment?

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[Usareke]

I had the system flushed and. I replaced all pads about 6 months ago but this is a new issue, my brake idiot light has came on though as well

If you unplug the tan wire from the combination valve does the warning light go out?

I do not know, I haven't tested anything with the prop valve yet

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[bd]

Thanks, I checked the pads a week ago, they were fine, I guess I'll go with new lines they are old and cracked, braided steel lines a good investment?

In spite of the hype, braided steel hoses don't function any better than OEM rubber hoses.  Occasionally they will test your patience getting them to fit correctly.  ...But, they look cool.   

At this point I suspect there is air in the lines, which caused the combination valve to trip and turn on the dash warning lamp.  If the dash lamp turns off when you unplug the tan wire from the combination valve, the valve is tripped because of a pressure imbalance between the front and rear brakes.  Before you replace the hoses, carefully check all of the lines, calipers and wheel cylinders for any evidence of fluid leaks.  Repair any leaks at the same time you install the new hoses.  As you bleed the system following parts replacement, you may need to center the differential pressure piston inside the combination valve to turn off the dash lamp and allow fluid to freely bleed from all four corners.  When the valve trips it isolates front from rear and occasionally needs coaxing to recenter.

[Usareke]

Thanks, I checked the pads a week ago, they were fine, I guess I'll go with new lines they are old and cracked, braided steel lines a good investment?

In spite of the hype, braided steel hoses don't function any better than OEM rubber hoses.  Occasionally they will test your patience getting them to fit correctly.  ...But, they look cool.   

At this point I suspect there is air in the lines, which caused the combination valve to trip and turn on the dash warning lamp.  If the dash lamp turns off when you unplug the tan wire from the combination valve, the valve is tripped because of a pressure imbalance between the front and rear brakes.  Before you replace the hoses, carefully check all of the lines, calipers and wheel cylinders for any evidence of fluid leaks.  Repair any leaks at the same time you install the new hoses.  As you bleed the system following parts replacement, you may need to center the differential pressure piston inside the combination valve to turn off the dash lamp and allow fluid to freely bleed from all four corners.  When the valve trips it isolates front from rear and occasionally needs coaxing to recenter.

Well thanks for the info guys it really helps, the light went off and I haven't done anything, but I guess I have some work ahead of me :/

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[Usareke]

I've had the same problem for a while now and I just. Checked all pads and hoses 3 days ago so I guess I'm gonna start with re bleeding the left driver's side and go from there. I've never gotten the dummy brake light but it could be broke or disconnected. The PV is the same one since '87 so we will see. I will post any progress as well if you wish since it is your thread Usareke

I'll keep it posted, I work at O'Reillys and I can't even get a new pv

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[Usareke]

I thought maybe I could get a new one for a quick fix but looks like it ain't gonna happen

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[Irish_Alley]

i split froto's post just cause his problem might be similar but its still his problem

[Usareke]

i split froto's post just cause his problem might be similar but its still his problem

Gotcha

Sent from my SAMSUNG-SGH-I317 using Tapatalk

[jg1977c20]

i'm voting on the left brake hose too , about 5 months ago had the same problem - then one day i went to leave the driveway and the front left tire momentarily stuck -( brake was applied due to collapsed hose ) .