Brake proportioning valve adjustment

[growler2058]

I havent read all the other posts but my understanding was the brake proportioning bracket was to be matched with the appropriate lift. Mine was sold to me as part of my 4" lift and have had no issues at all and it does seem to sit 100mm higher than standard (4")

[JoeG]

Hi Growlers
Yes the lever arm needs to be lenghtened when you fit longer springs
The issue I was refering to is when you fit air bags and raise the loaded height
If you raise the rear (back to unloaded height to remove the sag) when loaded with the air bags the proportioning valve then bleeds off brake pressure as the
Valve thinks the vehicle is unloaded.
Of course if you have ABS no problem as no load sensing valve, however one more thing to go wrong
Joe

[Boagie]

is it the same deal with leaf springs?---i have a couple of extra helper springs in my ute,and the rear brakes seem very toucy when unloaded !

[Boagie]

i meant touchey as in easily grabbed

[JoeG]

this is from the service manual

[macca]

Thanks Joe will have a look at that, have you jacked the rear axel and tested the brake effectivness?
Be interested in your thoughts.
Was told to do this on my last 4B and all of a sudden I had brakes again. Airbags had just been fitted and it thought the tray was empty as it sat higher.
Good luck mate
Macca

[JoeG]

Hi Macca
Yes jacked up the chassis then slight load on diff to simulate heavy braking
then tried 2000rpm and spring on and off.
it stalled every time
tried at 3000rpm same story always stalls
what i did discover is that the suspension lift did not include lengthening the arms for the rear sway bar and it bottoms out before the shocks- so will pull the arms off and lengthen 50 mm to match the lift- this should then make the sway bar work better if the bar is normally parallel to the road. the rain has finally stopped so can start on out side jobs
Joe

[damaverick]

I'm trying to adjust my brake bias valve... have clicked that link which takes me to another post which has a link to a PDF file which I can't seem to access. What's the go?

[Bigrig]

I'm trying to adjust my brake bias valve... have clicked that link which takes me to another post which has a link to a PDF file which I can't seem to access. What's the go?

Not sure why it's not working mate ... were you using the PC or tapatalk on a phone/iPad?

I just opened it from my phone an it worked ...

[Bloodyaussie]

Bumped this up so i can tinker tomorrow.