Brake problem

[jerod]

Have a 84 Silverado10 just bought to restore.  For a week when you pushed brake pedal it would jerk to the right then all of a sudden started pulling to left all the time and rotor getting hot on that side but still jerks to the right when you press on brake any idea of my problem this is my first restore and I'm learning as I go also the truck had been sitting undriven the last couple years

[roundhouse]

Have a 84 Silverado10 just bought to restore.  For a week when you pushed brake pedal it would jerk to the right then all of a sudden started pulling to left all the time and rotor getting hot on that side but still jerks to the right when you press on brake any idea of my problem this is my first restore and I'm learning as I go also the truck had been sitting undriven the last couple years

Sounds like the rubber flex lines at the wheel
they swell up inside and won't let the fluid  come back
Cheap and easy to replace

[Irish_Alley]

like round said. on my 94c10 it would jerk to the left then kind of pull to the right when released. got to the point where i could come to a stop and let go of the brakes yet the truck wouldnt move till you gave her some gas. turns out the right side. come to find out the metal mounting bracket on the hose itself rusted on the inside, restricting the fluid flow. this would cause the left side to work before the right hence the jerk to the right. then it would delay the amount of pressure released on the right side. hence the drag on the right side. able to diagnose it pretty simple. jacked up the front end, pushed the brakes and release spun the right side no problem left side was still locked up

[jerod]

Thanks for the comment ill replace the hoses as well as calipers tonight while got it all apart

[jerod]

Another question though the parts store wants to know if I have jb1 jb3or jb5 brake system and build sheet on truck long gone the best way to figure it out gonna be carry old ones up there and match them up?

[roundhouse]

Another question though the parts store wants to know if I have jb1 jb3or jb5 brake system and build sheet on truck long gone the best way to figure it out gonna be carry old ones up there and match them up?

I don't think it make mush difference

They wanted to know that for ours and not only do we not have a build sheet.  We don't have a VIN

Ours has a state issued VIN
So we have no clue


Plus the parts store couldn't tell me the difference in the three
We just got one of the three and installed it
It works much better than the old one

We figured even if it wasnt the exact one it would
Be better than no brakes at all which is what we had before

We just bought the one they could get brand new , not rebuilt

[CipherLogic]

Does anyone know the difference in jb1/3/5? I ran into this on the truck I am working on as well finally decided to pass over it an fix some other things in the mean time.

[roundhouse]

I think it has something to do with the rear wheel cylinders
But I've never found anyone that can tells what the difference is

I thought it might be the diameter of the piston
In the MC. But it didn't have that info in the computer at the auto parts store


Some of the F-150s
Had different
Ones

 
If you got the "camper special " it had a larger
Dia piston in the mc

[bd]

See:  Re: 2 questions about brakes and master cylinder....

[Irish_Alley]

this will help out also it has pictures. most times you can tell by the master cylinder

diesels come with JD3, JD5, JD6 and JD7
gassers come with  JB3, JB5, JB6 and JB7
now here's the kicker for gassers if its a plastic reservoir its a  JB3, JB5 or JB6
if its a cast reservoir its a JB7

If your a gasser you dont need this info but if its a Diesel then read on
if you reservoir looks like this

then you have a JD3, JD5 or JD6
if it looks like this

then its a JD7

JD7 (for diesles) and JB7 (for gassers) use the same cylinder
other than that gassers use plastic besides the JB7

[bd]

...and these...

• JB1 BRAKE, MANUAL, DISC/DRUM, 4300 LBS
  JB3 BRAKE, POWER, DISC/DRUM, 4600 LBS
  JB5 BRAKE, POWER, DISC/DRUM, 6400 LBS
  JB6 BRAKE, POWER, DISC, DRUM 7200 LBS
  JB7 BRAKE, POWER, DISC, DRUM 8400 L85
  JB8 8RAKE, POWER, DISC, DRUM 10000 LBS
  

  
  

• ...The only rear ends that have 13" brakes are the JB7 and JB8 brakes on a 14 bolt full float.
  
  10 or 12 bolt [rear axles] had either 11.15" x 2.75" for the JB5 or 11.15" x 2" for the JB3.
  

[SUX2BU99]

Mine did that too, jerked to the left because the right side was slow to engage and release. Going through the caliper and hose replacement right now. With the hose unhooked I couldn't even get fluid out when I pushed the brake pedal! Let me know how it was for you getting the passenger side hose off.

[jerod]

When I replaced calipers Friday night it did not fix problem but replaced hoses sat morning and brakes work perfectly now replacing the hose was kind of a pain unhooking brake line and getting the nut off inside of frame to release hose was a pain to get to and was rusted but glad I got it done

[SUX2BU99]

Glad you got yours done.  I'm still fighting with mine  Any tips about getting that nut off? Did you get the brake line flare nut off first and then the big nut? I can't get a 15/16" wrench in there, even a stubby. And the flare nut wrench I'm using doesn't want to budge the flare nut. Grrrrrrr