I have read elsewhere about putting rear disk brakes on our cars can be as easy as getting the rear suspension from a cobalt ss? I have an 07 ls that is pretty much bone stock. Did any HHRs come with rear disks standard? Is there any other donor cars possible other than a cobalt ss? Would it have to be from a sedan or coupe or no difference? What all do I need to make the swap? Thanks again.

 

Is there some reason that you need 2 threads on this subject? I deleted one of the first 2, then you started another.

 

HHR SS has the 4 wheel disc brakes. Here's something https://www.chevyhhr.net/forums/how-...r-ls-lt-62669/

 

The front disc brakes can also be upgraded to non Brembo SS 11.6 inch rotors and caliper brackets, inspect your lower control arm rear bushings , these can be deteriorated enough to the point the front brakes seem to have warped rotors .
if you desire to swap the rear axle beam for a disc brake one from an SS , you will need the eBrake cables and flex hoses , you have to use the rear hubs from your 2007 if you have ABS as the SS hubs are different voltage for the ABS .
I upgraded my front rotors and brackets , kept the calipers and replaced the rear drums and shoes , simply keeping them adjusted every oil change. If you think about the friction surface of the drum brake shoes compared to rear disc brake pads, I think you can see the drum brakes are superior in that department.
Your 2007 is 16 years old, so a new set of brake hoses front and rear , brake fluid flush and new rear brake cylinders make more sense, even if the don’t look as cool.

https://www.chevyhhr.net/forums/brak...ard-hhr-42938/

https://www.chevyhhr.net/forums/brak...le-swap-65119/


I’m thinking, a 13 to 15 year old SS rear axle beam would be ok to swap , but the calipers , hoses and cables should be new.

there’s photos in here from GaryB

https://www.chevyhhr.net/forums/brak...t-41839/page3/

 

Here's an idea: install the bigger discs and some EBC Greenstuff pads and you may not want or need rear discs. I did and I'm quite happy with the results. I may not be able to outrun 'em but I can now outbrake 'em!

 

This is true! With hard braking on clean dry pavement, the fronts are doing almost all of the stopping.

On other hand, if you have anything other than the stock 18-hole steel wheels, any disk in the rear will look a lot better than those microscopic drums, lol.

 

The friction surface of the 9” drum brakes is much larger than the disc brake pads contact surface.
I just painted the drums black


The black drums just disappear in the shadows

 

I swapped in the rear axle from an HHR SS. As noted above, I had to use my original hubs to retain ABS. I am still using the original disc/drum master cylinder.

Did I notice any difference in braking?

Yes, some subtle difference. First off, a slightly lower pedal. I'm talking maybe 1/4"-1/2" lower. Not enough to affect performance, but noticeable the first few times I stopped.

Second- the parking brake isn't as strong. It will still keep the car from rolling, but won't 'lock up' the rear wheels if pulled while moving. This may be an issue with the calipers, as I haven't changed them or the rotors yet. Could even be due to the type of pads. All of that stuff appeared to have been recently replaced, so I kept it.

Third- The SS brakes are tiny. They look small behind even a 17" wheel. Definitely cooler than drums though.

Finally- I haven't noticed an 'improvement' over drums. Maybe if you drive hard enough to heat the brakes, they won't fade as much, but mine is just a cruiser and I did the swap primarily for looks.

 

I used the rear beam from a Colbalt TC with new calipers and hoses.
Why?
I wanted to, I like the way disc brakes look in the back,
AND, not too many 2LT's have rear discs.

 

None of them came with them from the factory. My 08 Panel 2LT has every available option and still didn't have rear discs.