Diff into HQ?

[vkwalks39]

Gday guys, My old man has a Holden HQ sedan. He wants to change the diff. Cause now, he wants disc brakes instead of drums. He wants to know if he can put a diff out off a vr-vs commodore into the Hq? Your help would much appreciated Cheers Jason

[Darcon666]

No, would be my first guess... well not without some major modifications(To the diff & car rear end...)

[vkwalks39]

Cool, We are going to give a go! finger cross it might work lol thanks for your help mate...Cheers Jason

[Clutchy]

cant ya just find a hz disk rear end or something as id say the commodore diff will need alot of work to fit.

[GothicKidd]

I thought you could easily upgrade to disk brakes from the old Drums..

[vkwalks39]

Gday guys, i think hq diff with disc brakes are hard to find, aren't they? So I though a commodore diff would be a better option cause there are so many of them. How much is ti to change drums to disc? Jason

[GothicKidd]

Could find a place that works on brakes, and ask about it? Im not sure..

[Reaper]

As above - go raid the rear end out of a disk braked HX - WB and swap it across. The master cyl/proportioning valve will also be different from memory but it's a worth while upgrade. You may need the diff housing itself out of a wagon or 1 toner as HQ had leaf springs on the rear (can't remember that for sure though).

Reaper

[vkwalks39]

Thanks guys for advice, could we just change the brakes housing from drums to disc, it's a V8 diff, ratio is 3.36 he wants to keep it but change the brakes setup......... Cheers Jason

[Blown V6 Hatch]

As above - go raid the rear end out of a disk braked HX - WB and swap it across. The master cyl/proportioning valve will also be different from memory but it's a worth while upgrade. You may need the diff housing itself out of a wagon or 1 toner as HQ had leaf springs on the rear (can't remember that for sure though).

Reaper

HQ sedan (and wagon) ran 4 link and coil springs. Ute, van and 1 tonner ran leaf springs.

Thanks guys for advice, could we just change the brakes housing from drums to disc, it's a V8 diff, ratio is 3.36 he wants to keep it but change the brakes setup......... Cheers Jason

Yes, you can bolt the disc brake set up straight onto the existing diff, however you will need to change either the wheel bearings or the complete axles as the wheel bearing is different on a disc brake set up. You can use the disc brake set up from any HX-WB (including statesman).

[vkwalks39]

Cool thxs mate, I'll tell him. my oldman just had a operation on his back, so the Q will be on hold for a while thanks heaps guys for you help, very much appreciated Cheers Jason.

[the_boozer]

Yes, you can bolt the disc brake set up straight onto the existing diff, however you will need to change either the wheel bearings or the complete axles as the wheel bearing is different on a disc brake set up. You can use the disc brake set up from any HX-WB (including statesman).

I think it was only statesman's (hz-wb) that had disks on the back good luck finding 1 then more than likely it wont be 3.36 (also hard to find now), either talk to hoppers stoppers there right into brake conversions or go the commie diff conversion and get the axles re-drilled to hq pattern. Don´t know what ratios v8 commodores then there will be proportional valve , master cylinder and ginger beers
I been trying to find a wb statesmen disk brake diff and axles for yonks cant even find a 2.6 (not that I want 2.6 but that's what most would have been).
My old tonner HZ 308 turbo 400 factory air power steering has drums on the back , I don´t think disks where an option back in 79.
If you go a commodore diff go vs or after when did the hand brake become all 1 piece that type

[Blown V6 Hatch]

I think you will find that prems could be optioned up with 4 wheel discs. You must be looking in the wrong places because WB statesman disc brake set-ups aren't that hard to find.

Doesn't matter what ratio he finds as it will all bolt straight onto his existing 3.36 diff.

You can also bolt a Commodore disc brake set-up onto a Salisbury, all you need to do is have the backing plate machined down where it bolts behind the axle to the same thickness as a drum brake backing plate so the drum brake bearing & seal works. Everything else will bolt straight up, all you need to do is get a custom handbrake cable made up. I did this many years ago on the back of my Torana with a Salisbury, worked a treat (Now i run Commodore axles, so no mods are needed).

[vkwalks39]

The 3.36 diff is a v8 diff, we change the diffs cause it use to have a 6's in it but now its going to have a 308. 2morrow i'll let him know. tthanks heaps guys.