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Parking brake column and question

The Show
#1

Regarding your article on automatic parking brakes on May 23. In the old days, the parking brake used to be called an “emergency brake”. Many years ago, I had occasion to use this feature. The previous owner of my 1954 Mercury had installed a duel exhaust system with one of the tail pipes too close to a rear brake line. Eventually the chafing wore through the brake line and I lost all the brake fluid. I used the transmission’s lower gears to slow the car and then the emergency hand brake to stop the car.

Can I use my parking brake in the same way on my Lexus if the main brakes fail? Also, if I buy a car with an automatic parking how could I use this to stop the car? Thanks.

#2

Ray doesn’t post here but yes, you can use the parking brake as an “emergency brake.” Do be forewarned that it will only affect the rear wheels so use it carefully on slick pavement. As for an automatic parking brake, I would think there would be a lever or pedal for manual use. If you’re concerned, make sure your next vehicle has a parking brake that can be operated manually.

#3

The issue with the 54 was solved in 1968 when dual master cylinders were mandated. Only half the brake system was allowed to fail if a leak occured.

#4

Yes, but the problem with electronic e-brakes is that they are “all on” or “all off”, and when a modern electronic e-brake is activated, it will lock the rear wheels.
The Owner’s Manual for my Outback suggests that the e-brake be activated/deactivated rapidly in that type of situation in order to prevent total lock-up, but this would surely be difficult to modulate.

#5

I guess Michael is calling the electric parking brake ( an automatic parking brake ) .

#6

I think so.
I recall that my uncle’s '64 Imperial automatically applied the e-brake when he put the transmission into “park”, and that it automatically released it when he put the trans into “drive”, and IIRC, Cadillacs of that era had the same feature. By contrast, the modern electronic e-brakes with which I am familiar require the driver to activate them with a button or some other type of control.

On my Outback, it automatically releases when the trans is put into “drive”, but only if the driver’s seatbelt is latched. If you don’t have your seatbelt latched, then you have to release the e-brake manually.

#7

“EPB mechanisms work with the anti-lock braking system, as the electronics are integrated” https://www.thecarconnection.com/news/1050069_electronic-parking-brakes-whats-the-point