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by vvillena 811 days ago
Why do people rely on automatic gearboxes to keep cars in place? Trusting the "park" position is like leaving a manual gearbox car in gear: it can do the job, but it's not the right tool for the purpose. The handbrake is there for a reason.
4 comments

I use both in a manual. Cheap insurance. Handbrake, and in gear in case the handbrake fails.

But I’ve never seen the driver of an automatic set the parking brake. Never. That gear is “park” so they use it when they park.

Only driving manuals, I have to really remind myself not to in somebody else’s car because it is probably going to stick as a result of never being used.

I don’t drive manuals now because my wife hasn’t been able to leadn how, but I am adamantly teaching my daughter to always set the parking brake when parked. What frustrates me is this finicky push button electronic parking brakes, I want a good mechanical handbrake or even a 3rd pedal parking brake.
Aeons ago I paid $50 to a manual shifting driving instructor to teach my wife to drive manual. It saved our relationship and she drove stick better than me as a result. The instructor’s trick was to show how a clutch works then he had his students get the vehicle moving from a stopped position by only feathering the clutch pedal. He wouldn’t let them use the accelerator pedal. Once they learned where the engagement happened in the pedal’s throw the rest was easy.
Thanks, we are probably past the age and epoch of when paying to learn manual would make sense for DW, but would like my kids to learn. That is so true, finding that spectrum of clutch petal engagement was crucial. I remember when I first learned stomping on the clutch, treating it as a binary mode rather than a gradient.
The position is "park" because it parks the gearbox mechanism, not the car. It's clear that many people misuse it, to the point that manufacturers overengineer the gearbox lock so it's able to serve as a parking brake.
I think I witness that VW automatically engage the electronic handbreak as the driver opens the door while the stick is in parking position.
I always use mine, but yeah I run into a lot of other automatic owners who don't.

I'm guessing it starts as a habit, they either weren't taught in driving class or it wasn't enforced, then it became ingrained and they never got curious about what they could be wrong about,or what it means that their car rocks when they step out.

Even with a "car guy" who was working on my rear wheels (fwd) he asked if I had AWD. No buddy, I just remembered to set the brake before you got it up on the jack.

For curious readers, if you always park on level ground, just set the brake anyway as a drill. If it's busted, you'll get a chance to fix it before you need it

I also always turn my headlights on. It uses a little more gas but saves the judgement call of wondering whether it's real dark enough or whether the computer will turn them on for me. Always on.

All aspects of the way other people drive are horrifying but one of the worst things is drivers with automatic transmissions who don't use the parking brake, and their car lurches 6 inches when they are getting out. If you stop the car, set the parking brake, and shift into park the car will not move when you release the brake. It feels so much better and you won't look like a loser.
When I turn off Toyota hybrid it engages parking break automatically. Why wouldn't it?

Is it possible for modern car to be off in neutral?

My Pacifica does this as well. Shifting to park also engages the parking break.
This is not at all true.

Parking brakes in an automatic vehicle actually flip a piece into the gear ring. They’re absolutely rated to hold the vehicle in place without additional brakes.

I know on my Ford truck, the parking gear is rated to hold the truck plus some amount of trailer weight. If you’re above that trailer weight, they recommend engaging the manual brake.

Park position flips a lock into the gear ring to ensure the gearbox doesn't move. This achieves the same effect as leaving a manual gearbox in gear. In a manual gearbox, the engine holds the rest of the gearbox in place, but in a traditional auto gearbox, the whole mechanism can still move when the engine is stopped, that's why the lock piece is needed.

People relying on the gearbox lock to keep the car in place is the weird part - it would be like engaging first or reverse gear on a manual car, and trusting that to keep the car in place. Even if the manufacturer showed that the engine vacuum is enough, people still rely on the right tool for the job - a brake.

> This achieves the same effect as leaving a manual gearbox in gear

This is not true. In a manual car, you’re still relying on the engine. In an automatic vehicle, it’s essentially a latch that drops into place. A well designed one should actually tighten as the vehicle attempts to roll while in park.

It seems these are failing to engage or simply failing entirely.

Not quite the same - automatic transmissions have a pawl that locks the axle in place, it’s not just the engine like in a manual transmission.
The lock is there because traditional auto gearboxes can still move when the engine is stopped, as if it was in neutral position, while a manual gearbox in gear has to overcome the engine cylinder vacuum. The difference is people not trusting the cylinder vacuum to keep the car in place, but at the same time happily relying on the gearbox lock to do the job.
I've used the standard Park for 15 years without ever having any issue