re: Best practice to use hand-brake while parking Just a few thoughts/comments on parking on an incline and whether it makes a difference which gear to use. Facing downhill / uphill and so on.
What you want is maximum friction from the engine, through the clutch and transmission and wheels. The gear that will give you the most friction in this fashion is (almost always) reverse gear. Simply as it tends to be the lowest gear ratio in your (manual) box.
So whether you face the car uphill or downhill for maximum friction (staying power) on top of your parking brake select reverse gear.
The commotion/debate on first/reverse/uphill/downhill has a different, technical, background. The idea is that when the car does roll, in gear, it means the engine is turning. And you want to make sure it turns in the correct direction. Because if it doesn’t, your oil pump won’t work. Technically this is correct. The wheels will be driving the engine through the transmission and clutch.
However, I am not quite sure how relevant it is. Because your car is either in reverse or first gear and just rolling slowly away. That means the engine is not turning over very fast. And unless it is a very long downhill run, you are likely to suffer more damage to the car getting dented as it bumps into something than problems due to severe oil starvation.
In general it is not advisable to turn an engine against it’s normal turning direction. Unless so specified in the workshop manual. It is not just the oil pump that won’t work correctly. Also, the tensioners, in particular on timing chains, might cause the timing chain to go slack. Worse case, you have a piston slamming into a valve, or a chain jumping a tooth. But that is, to be honest, not very likely, but it is not completely fictional either. Especially on old, high mileage engines with timing chains.
If you want to get engine oil protection you would have to put it into the highest (manual) gear. You will have less friction, but the oil pump will spin faster if it does roll! (Will only work when facing the front of the car downwards of course)
What is advisable as some other members have already pointed out, is to ensure your front wheels are turned toward the curb in such a fashion, that if the car does roll unexpectedly, it rolls into the curb.
Funny things parking brakes. I remember an incident from many years ago. 1981-82. My (to be) wife and I were living in Brighton, UK. On a Sunday I went out for a walk, or to get something from the shops. Parts of Brighton are very hilly and pretty steep and we lived on the hilly part.
I was walking, minding my own business, when all of a sudden in the corner of my eye, I caught a car coming down a playing field in the middle of the estate, which was on a hill. Luckily there were no kids or anybody on the field.
It rolled down the hill picking up speed and at the bottom of the hill it crashed into one of these concrete park benches. Which was sort of good, otherwise it would have ran into the road, maybe crashing into moving cars, or certainly crashing into the many parked cars.
I rushed over. Nobody in the car, doors locked. Eventually we managed to find the owner. He lived at the top of the hill. He had parked his car the night before in front of his home, put it on the parking brake (we could still see it was on).
Somehow, some 12 hours later, something must have happened, gravity pulled on his car, overcoming the friction of the parking brake and it rolled all the way down the hill. Quite amazing!!
Anorak fact:
On my jaguar XJR 1st gear is lower than reverse!! However, this is an automatic with a conventional convertor. I can’t even manually select 1st on this car. It has to be put into Sports Mode. It will only use first when you floor the accelerator into the kickdown in Sports mode. Otherwise (i.e. 99,9999% of the time) it pulls away in second gear. That is a 4.0L Supercharged V8 for you!!
Summary:
You want maximum friction/holding power: put it in reverse, front facing upward
You want to ensure the oil pump turns in the correct direction if it does roll, front downwards 1st, front upwards
You want to ensure the oil pump runs at the highest RPM, select highest gear and park facing downwards.
Always turn your front wheels so when the car rolls it will bump into the curb.
Hope this helps!!
Jeroen
Last edited by Jeroen : 30th December 2022 at 00:34.
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