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Old Nov 19th, 2016, 00:02   #33
Christerart
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Quote:
Originally Posted by richardbell556 View Post
..engine braking still allows your caravan brakes to work on steep grades but allows the tow car brakes to rest/cool an art long lost with modern cars . still used today by hgv drivers to avoid runaways...

Quote:
Originally Posted by richardbell556 View Post
..engine braking still allows your caravan brakes to work on steep grades but allows the tow car brakes to rest/cool an art long lost with modern cars . still used today by hgv drivers to avoid runaways...
Actually, in the States, truckers, what you here call HGV drivers, depending on what kind of truck and engine/transmission combination they have, usually have something called a "Jake Brake":

https://en.wikipedia.org/wiki/Compre...e_engine_brake

This system - in the US (often you have three levels of "power" - for example a 6 cylinder diesel will then turn on 2, 4 or all 6 of the cylinders) works in such a way that as soon as you lift your foot from the accelerator, the "Jake" kicks in and retards the vehicle without using the regular brakes - in other words without wearing the brakes. Many leave it on all the time, except when it's slick - i.e.,. rain, snow, ice.

I understand that here in the EU you have to also apply some power to the brakes, which to me defeats a lot of the smoothness of using the system as it becomes second nature to use the Jake as a brake simply by lifting your foot, important when you spend 10 - 15 hours a day behind the wheel and 600 - 700 miles.

On the other hand, you don't use the Jake when it's slick as engaging it can be enough for the drive wheels on the semi (the towing vehicle) to break loose, possibly jackknifing the truck.

And the major rule still is; you go down the hill in the same gear you went up - i.e. - 3rd gear up, 3rd gear down..=*^)

A few examples of Jake Brakes - here's a competition for the LOUDEST Jakes (competition starts at about 06:00):
https://www.youtube.com/watch?v=pHTrEwRk0MU
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Last edited by Christerart; Nov 19th, 2016 at 02:25. Reason: including examples of Jakes
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