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Comment by swiftcoder | Hacker News Reader

The first time I had a flat on an electric Kia, the guy at the local garage and I spent 20 minutes figuring out how to disengage the parking brake. In the end, he did the wheel change with the car powered on, as that's the only mode where one can disengage the electronic parking brake...

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Maybe I'm missing something obvious, why did you need to disengage the parking brake? You can change a wheel with the brake on, in fact I don't think I've ever done it with the brake off?

The oldschool way of installing wheels is not hammering them down with a pneumatic impact wrench in 5 seconds and calling it a day, but rather tightening each screw slightly and incrementally in an X pattern while slowly rotating the wheel, so as to make it seat as centered as possible (a questionable point, the hub should center it regardless) and without unnecessary remaining stresses (a valid point), and only then tightening with the full recommended torque.

I'm all for the careful oldschool way.

Most people doing the right thing use a torque limiter to "gun" the wheel on and then set final torque with the tires just touching the ground (for friction) which is totally adequate.

The thing people might forget is to clear the corrosion off of the wheel and hub which can be a problem if it breaks away as you drive.

I never saw a guy turn the wheel, it doesn't make sense. Wheel is mated to rotor, any misalignment of rotor to the rest of the assembly doesn't matter.

I do the incremental X pattern, but never thought to rotate the wheel while doing it.

The rationale is that it kind of applies radial forces in varying directions when you rotate the wheel, and if there's any tiny slack between the hub and the wheel, helps make that slack 100% concentric while the wheel is still able to slide against the hub.

But honestly I do that simply for the peace of mind :) A soothing personal idiosyncrasy inherited from my dad.

You know, I have no idea. Maybe he was trying to hunt for the hole before deciding to swap it (they often do the rubber plug thing here for minor punctures)

https://www.kiaevforums.com/threads/ps-747-maintaining-neutr...

For future reference.

How is it that the park brake needs to be disengaged to swap a wheel.

Genuinely curious, as that isn’t the case for any of my ICE vehicles.

A few years ago I used to help my father replace wheels in his car shop.

The lift was rather small and you couldn't get out of the car easily when you placed the car in the correct position for the lift's arms. We placed the car about a meter from the correct position, got out, pushed it forward and placed the arms.

For this to work you need to make sure the parking brakes are not engaged.

This isn’t an answer to the question I asked.

Yep, I was an idiot and replied to the wrong comment. Sorry for that.

You do realize that jacking up a car on one side without the parking brake is quite dangerous because the car could just roll away?

Relying on only the parking brake like you describe is also dangerous. Put car in gear and/or use a wheel chock as well.

This was not on jacks, it's a small garage, but they raised the car on a proper lift

No amount of Reddit-ish always-isms and rules of thumb will make lifting and lowering objects this heavy not fraught with hand mangling peril if one is stupid or careless.

Chocks, deflating a tire or two, parking against a tree or another car with a working parking brake, ratchet strap through the wheel spokes to something solid, etc, etc, where there's a will there's a way.

given it was a mechanic garage they probably used a lift... or at least had some wheel chocks.

But yes, YT have plenty documentaries on that, together with "hydraulic jack is enough, I won't bother with jack stands"

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