Can anyone name this rear brake part?

[SLE-883]

It's the valve that connects the brake line to the two rear calipers and bolts on to the diff. I'm in the process of sorting out the rear end and want to get a new a new part or reconditioned the original

[ari666]

proportioning valve?

[VN_Luke]

t-piece and/or bracket.... it's just a bit of metal with some holes in it, there's nothing to rebuild just clean it up and be done with it.

[SLE-883]

Is it just a T piece? I thought it was a proportioning valve (that's what a make said) but when I tried to research it I couldn't find any info on the part.

I did read some where that with all post 1979 commodores, the proportioning valve was incorporated into the Master Cylinder.

[VT-565]

I did read some where that with all post 1979 commodores, the proportioning valve was incorporated into the Master Cylinder.

My VG had a proportioning valve. You'll probably find that all the live axle commodore utes had them.

[VN_Luke]

I just assumed it was a t-piece and the valve was built into the master cyl - the pic looks to be a sedan, but I know tonners/utes etc in general use a variable proportioning valve with a connection to the tray that adjusts brake bias based on load in the back.

I guess whether it's a "proportioning valve" or a "t piece" is only determined by the diamater of the inlet hole or obstructions? which still shouldn't need reconditioning/replacing due to presumably nil moving parts etc?

You could probably measure the hole dia. on a drum brake and a disc brake commo to determine whether or not it's a proportioning valve? or eyeball for a pin/restriction? - I have one floating around the shed I'll check out when I get a moment

[VN_Luke]

Okay upon further reading, it looks like commodores do run an in-built proportioning valve in the master cylinder.

The "cracking pressure" of this is stamped onto the master cyl somewhere in the format "C###" where the #'s are the cracking pressure in PSI.

From a quick read there's various pressures available - for old holdens, anyway - they were c225, c350 and c450 for drum/ute/disc. Allegedly commodore Utes use a C000, which would make sense - so 0psi cracking pressure, and the proportioning valve in the rear takes care of the bias? And sedans/wagons with drum/disc would presumably get the appropriate valving in the master cyl, and just T piece at the rear? ... interesting though for people doing VT front brake upgrades and retaining standard rears..

Here's some resources.
Identifying this master cylinder - GMH-Torana
Prop Valve - GMH-Torana
Brake Proportioning Valve - Holdenpaedia

[Blown V6 Hatch]

It's just the end of the flexible brake hose, it just directs the fluid to each caliper. If you buy a new flexible hose, it will come with the metal end already attached, screw in the metal lines and you're done. If there is nothing wrong with the flexible hose, then don't worry about it. Nothing to rebuild there as VN_Luke said.

Only utes have a proportioning valve at the rear, which is governed by the load/weight in the tray.

[SLE-883]

Thanks everyone

I'm replacing all the brake hoses with new ones so I might as well replace this hose and t piece/