WB Callipers

[Valencia]

Just wanting to know if WB callipers are better than HZ ones
someone told me they are better something about the pistons
is there a difference
cheers G

[HK1837]

I'd use whichever are in the best condition if you have both. I assume you are talking about both being the bigger pad Girlocks?

[Dr Terry]

It depends which HZ calipers you're comparing.

Most HZ got the PBR alloy caliper, which was rubbish. Later ones got the Girlock alloy 'Collette' caliper which looks similar to early Commodore calipers; these are much better.

The only difference between the HZ Girlocks & WB Girlocks is the attachment of the hose. HZ use 3/8" UNC thread, while the WB uses a 10mm banjo bolt differently located to the 'side' of caliper housing. Otherwise they share the same pads & mounting & are as good as each other.

Dr Terry

[SLR_dave]

Funny. Im with Byron. Use the best ones you have.

But... then if I think about it I recall I have been here, I considered the alloy piston sleeves dont corrode like the steel ones, however even now 40 years on a decent brake shop can usually clean up a pitted steel piston to serviceability and 2nd hand replacements are everywhere and then a dude in a reputable brake shop explained to me the steel ones (lockheeds I think they were) are better brakes, I asked why he said they dont flex, but the alloy ones do.... ummmn I was a bit skeptical on that, I decided its much of a muchness, but from memory, I went with aloy PBRs on one van Girlocks on the other van and the HJ wagon has its original steel Lockheeds. To be honest, the brakes on these cars were pretty good for the day, so best bet is to use the best ones you have. No point replacing servicable parts with 'more desireable' parts if the more desireable parts can not be reconditioned to the same standard as the serviceable parts you already have can be I reckon anyway.

(Didnt mean to seem to contradict Dr Terry, the posts occured at the same time).

[Valencia]

Thanks for all the info yes i was talking about the Girlocks but my Sandman being 10/77 would it have PBRs
to tell you the truth im not sure what mine has got
and im not about to check the spider infested brakes after all it has been in hibernation for 20 years
cheers G

[HK1837]

It is a lottery in my experience Gene, could be either and you don't know what has been changed since. People do bag the alloy PBR's too but the only problem i've ever had with them is lack of maintenance, so siezed/stripped bleed valve or buggered slide rubbers and lack of lubrication on the slides. Once they were overhauled and regularly maintained worked fine for years - I had them on my LX when I upgraded to A9X brakes and couldn't be bothered machining Girlock caliper carriers to fit.

[Dr Terry]

A 10/77 HZ will have the alloy PBRs, the Girlock alloys didn't eventuate until mid/late 1978.

There are basically 5 different front caliper types for HQ to WB, which become 7 when you get down to the finer points.

Firstly Girling & Lockheed merged around 1970 to become Girlock, so you shouldn't be seeing any Lockheed branded stuff on HQ-WB. You do see Girling branding on HD/HR calipers, HK & some HT/G. AFAIK the only Holdens to use Lockheed stuff was HB-TA 4-cyl Toranas.

The various caliper types are as follows:-

1. Cast Iron PBR: (2 types virtually interchangeable) Kidney shaped pads, a bit heavy but very reliable long term, good choice of pad materials & good brakes.

2. Cast Iron Girlock, largest pads, very heavy (heaviest of all) choice of pad materials limited, reliable long term & good brakes.

3. Alloy PBR (2 types), smallest pad area, limited pad choice, unreliable sliders, noisy & sticky unless lubed regularly.

4. Girlock alloy (HZ Collette), good braking, reliable, lightest of all, limited pad choice.

5. Girlock alloy (WB Collette) same comments as HZ Girlock.

Dr Terry

[SLR_dave]

That seems pretty definitive, great post. This is really useful if you happen to have a variety of calipers off donor cars and are wondering which ones to choose, wish I had been able to find that information so neatly explained at the time I chose mine.

[damienengland]

Hi all. Looking for some help with rear calipers. I have the 'Girlock alloy (WB Collette)' rear disc brakes and tried to replaced pads yesterday. Couldn't get the piston to retract so gave up and put them back together. After Googling around, it looks like the pistons rotate to retract not push? Can anyone advise on this? Any tooling or technique required?

[george]

you can buy a special tool to rotate and retract the brake cylinders or like some do long nose pliers and a screw driver for leverage.