Engine braking

[Chaoz2030]

Ive been enjoying this game alot lately. I drove a KW for a year in real life and I got to say this game is pretty damn realistic. Except for one area that kinda bugs me engine braking. I can go from gear 13 down to gear 5 with almost no noticeable decrease in speed. Maybe I am not doing something right in the game but in a real rig going down that many gears should slow me down considerably. Its not a huge deal I can just hit the air brakes but it kinda break immersion for me. Is there a mod that fixes this?

[B_Wald]

No mod needed- you need to activate the jake brake. If you're already using it, you can set a key to increase its intensity.

Check your "keys and buttons" menu, and set keys for engine brake increase and decrease.

[Chaoz2030]

Originally posted by B_Wald:

No mod needed- you need to activate the jake brake. If you're already using it, you can set a key to increase its intensity.

Check your "keys and buttons" menu, and set keys for engine brake increase and decrease.

So there is a button that makes your rig more sensitive to engine braking? Not jake braking but it effects how much the rig slows by downshifting?

[Trucker_71]

Don't use auto engine break, assign a button.

[DLM]

Not a trucker so pardon the question but I never understood the need for an input for engine brake, isn't it supposed to be automatic when you decrease your gear? It sure is in a car.

[Beltane]

Originally posted by DLM:

Not a trucker so pardon the question but I never understood the need for an input for engine brake, isn't it supposed to be automatic when you decrease your gear? It sure is in a car.

I guess OP is rather talking about the additional brake sytems that truck boast. Those are commonly called engine brakes as well, which might confuse people who don't know too much about trucks. Has nothing to do with "simple" downshifting though.

Theres exhaust brake for example, which use backpressure from the exhaust stream to slow down piston movement and therefore the engine as a whole.

Basically the idea behind all the techniques that exist is, to have a frictionless braking system that allows for safe downhill descents. Normal Servicebrakes just don't cut it there, and even if, it would drastically increase wear and tear on those.

[Bobby]

Originally posted by Beltane:

Originally posted by DLM:

Not a trucker so pardon the question but I never understood the need for an input for engine brake, isn't it supposed to be automatic when you decrease your gear? It sure is in a car.

I guess OP is rather talking about the additional brake sytems that truck boast. Those are commonly called engine brakes as well, which might confuse people who don't know too much about trucks. Has nothing to do with "simple" downshifting though.

Theres exhaust brake for example, which use backpressure from the exhaust stream to slow down piston movement and therefore the engine as a whole.

Basically the idea behind all the techniques that exist is, to have a frictionless braking system that allows for safe downhill descents. Normal Servicebrakes just don't cut it there, and even if, it would drastically increase wear and tear on those.

Fascinating. Thanks for the input. The other side of using constant physical brakes is of course the potential for them to catch fire. Being drum brakes which really like to keep the heat in! I watched also prog on TV at the weekend showing the fire brigage hosing down the drum brakes on an American rig on the freeway, showing a thermal reading of 250c. The shoe had stuck on with the constant braking.

[Elwenil]

A bit of background for those interested:

Diesel truck engines are a bit different from a typical gasoline passenger vehicle engine. A gas engine will typically have a fair amount of "engine braking" simply due to the timing and relation of the pistons and valves. Diesel truck engines are made differently and the truck's weight can easily push them over the redline without slowing down the truck at all. For this reason exhaust brakes and Jacobs Brakes ("jake brakes") were invented to allow the engine to rotate normally, but with increased resistance to help control the downhill speed of the truck. Jake brakes are somewhat automatic, meaning they need a switch to "arm" them, but once on they are controlled by the throttle. As long as you are on the throttle, even just a little to maintain speed, the jake is off, as soon as you let off the throttle, the jake comes on and starts slowing down or at least maintaining the speed of the engine. How effective the jake is, depends on the incline the truck is going down, the weight of the truck, the size of the engine and how the jake is designed. Some jake brakes have multiple stages, others only have one.

You can't have a jake "on" all the time, in real life at least, due to the need to down shift. To down shift a truck with a manual transmission, you have to match the speed of the engine to the lower gear. This is a rough example, but if you are doing 30 MPH in 5th at 1,000 RPM and want to down shift to 4th, where the engine would be at 1,500 at 30 MPH, you need to push in the clutch, take it out of 5th gear, release the clutch, rev the engine to 1,500 RPM, push in the clutch, shift into 4th gear and release the clutch. Since a jake is designed to hinder the engine's revolutions, without the weight of the truck pushing against the engine, the jake will quickly take the engine down to idle speed when you push in the clutch and trying to rev the engine back up and shift into the lower gear would be near impossible. Especially considering that the truck may be travelling down hill and accelerating on it's own due to gravity and the truck's weight and quickly exceeding the speed range of the lower gear. This is why at the top of many long downhill grades you will see signs that say "Trucks Use Lower Gear". A truck driver with a manual transmission must select the correct gear for the decent before going down as once the truck starts gaining speed it will be far too late to downshift and the driver must rely on the truck's brakes to keep from overspeeding the engine. On a long grade and with a full load it can be easy to "smoke" or overheat the brakes causing them to become ineffective and the truck then becomes a "runaway". This is why some steep grades will have Runaway Truck Ramps, as an emegency method of stopping a truck with no brakes. This is why jake brakes are so important in trucking.

[HunterKiller]

The jacob brake is sort of like a compression release on a dirt bike if, you've had one installed. It slows the motor down without having to be hard on the brakes. When racing dirt bikes at a younger age, the compression release was a great addition to my bike.

[Bobby]

Originally posted by Elwenil:

A bit of background for those interested:

Diesel truck engines are a bit different from a typical gasoline passenger vehicle engine. A gas engine will typically have a fair amount of "engine braking" simply due to the timing and relation of the pistons and valves. Diesel truck engines are made differently and the truck's weight can easily push them over the redline without slowing down the truck at all. For this reason exhaust brakes and Jacobs Brakes ("jake brakes") were invented to allow the engine to rotate normally, but with increased resistance to help control the downhill speed of the truck. Jake brakes are somewhat automatic, meaning they need a switch to "arm" them, but once on they are controlled by the throttle. As long as you are on the throttle, even just a little to maintain speed, the jake is off, as soon as you let off the throttle, the jake comes on and starts slowing down or at least maintaining the speed of the engine. How effective the jake is, depends on the incline the truck is going down, the weight of the truck, the size of the engine and how the jake is designed. Some jake brakes have multiple stages, others only have one.

You can't have a jake "on" all the time, in real life at least, due to the need to down shift. To down shift a truck with a manual transmission, you have to match the speed of the engine to the lower gear. This is a rough example, but if you are doing 30 MPH in 5th at 1,000 RPM and want to down shift to 4th, where the engine would be at 1,500 at 30 MPH, you need to push in the clutch, take it out of 5th gear, release the clutch, rev the engine to 1,500 RPM, push in the clutch, shift into 4th gear and release the clutch. Since a jake is designed to hinder the engine's revolutions, without the weight of the truck pushing against the engine, the jake will quickly take the engine down to idle speed when you push in the clutch and trying to rev the engine back up and shift into the lower gear would be near impossible. Especially considering that the truck may be travelling down hill and accelerating on it's own due to gravity and the truck's weight and quickly exceeding the speed range of the lower gear. This is why at the top of many long downhill grades you will see signs that say "Trucks Use Lower Gear". A truck driver with a manual transmission must select the correct gear for the decent before going down as once the truck starts gaining speed it will be far too late to downshift and the driver must rely on the truck's brakes to keep from overspeeding the engine. On a long grade and with a full load it can be easy to "smoke" or overheat the brakes causing them to become ineffective and the truck then becomes a "runaway". This is why some steep grades will have Runaway Truck Ramps, as an emegency method of stopping a truck with no brakes. This is why jake brakes are so important in trucking.

+1 superb info 👍

[Cmdo.Delta]

Some of you should make a guide about different breaks and how/when to use them :P

Its all kind of feature noobs like me don't understand anything about and since the game has no tutorial... ;)

[Leetpandaz]

Are we talking about Jakes here?
I found that with jakes enabled, i dont bleed a lot of speed. Its enough when doing a highway run and i want to slow down a bit, but on steep downhills i can usually hear the engine speeding up even with jakes set to max. A bit of retorder(spelt for censors) keeps it in check.

[Trucker_71]

@Elwenil I retired a few years ago from trucking after 45 years on the road, yup, I'm an ol' phart, but I could never explain the jake brake in such a detailed manner. Good job Elwenil. ;-)

[Chaoz2030]

Originally posted by Elwenil:

A bit of background for those interested:

Diesel truck engines are a bit different from a typical gasoline passenger vehicle engine. A gas engine will typically have a fair amount of "engine braking" simply due to the timing and relation of the pistons and valves. Diesel truck engines are made differently and the truck's weight can easily push them over the redline without slowing down the truck at all. For this reason exhaust brakes and Jacobs Brakes ("jake brakes") were invented to allow the engine to rotate normally, but with increased resistance to help control the downhill speed of the truck. Jake brakes are somewhat automatic, meaning they need a switch to "arm" them, but once on they are controlled by the throttle. As long as you are on the throttle, even just a little to maintain speed, the jake is off, as soon as you let off the throttle, the jake comes on and starts slowing down or at least maintaining the speed of the engine. How effective the jake is, depends on the incline the truck is going down, the weight of the truck, the size of the engine and how the jake is designed. Some jake brakes have multiple stages, others only have one.

You can't have a jake "on" all the time, in real life at least, due to the need to down shift. To down shift a truck with a manual transmission, you have to match the speed of the engine to the lower gear. This is a rough example, but if you are doing 30 MPH in 5th at 1,000 RPM and want to down shift to 4th, where the engine would be at 1,500 at 30 MPH, you need to push in the clutch, take it out of 5th gear, release the clutch, rev the engine to 1,500 RPM, push in the clutch, shift into 4th gear and release the clutch. Since a jake is designed to hinder the engine's revolutions, without the weight of the truck pushing against the engine, the jake will quickly take the engine down to idle speed when you push in the clutch and trying to rev the engine back up and shift into the lower gear would be near impossible. Especially considering that the truck may be travelling down hill and accelerating on it's own due to gravity and the truck's weight and quickly exceeding the speed range of the lower gear. This is why at the top of many long downhill grades you will see signs that say "Trucks Use Lower Gear". A truck driver with a manual transmission must select the correct gear for the decent before going down as once the truck starts gaining speed it will be far too late to downshift and the driver must rely on the truck's brakes to keep from overspeeding the engine. On a long grade and with a full load it can be easy to "smoke" or overheat the brakes causing them to become ineffective and the truck then becomes a "runaway". This is why some steep grades will have Runaway Truck Ramps, as an emegency method of stopping a truck with no brakes. This is why jake brakes are so important in trucking.

Wow what a good answer you know way more then I do about the subject. Mt orginal question wasnt about the Jake brake but about downshifting in general. Maybe my truck had some kind of automatic engine breaking I have no idea, but when I was driving even fully loaded I could slow my RPMs, downshift, my RPMs would skyrocket and my truck would slow down. In the game if I down shift I notice no speed decrase except for the normal my foot is off the throttle slowdown. From your explination it sounds like Trucks are supposed to be like that I have no idea why mine was differant. It was a 2014 KW I don't remeber the model. I did use the Jake from time to time but it was rarly needed because I could just downshift. The exception being downhills I would use the jake alot downhills.

[Chaoz2030]

Originally posted by Leetpandaz:

Are we talking about Jakes here?
I found that with jakes enabled, i dont bleed a lot of speed. Its enough when doing a highway run and i want to slow down a bit, but on steep downhills i can usually hear the engine speeding up even with jakes set to max. A bit of retorder(spelt for censors) keeps it in check.

Jake is only effecrtve if you have higher RPMs so you have to downshift in order to keep it useful. So Jake on in 10th gear wait till RPM is around 1300, turn offf jake, downshit, RPM jumps up, turn on jake, repeat. If you keep it in the same gear and turn on jakes once your RPM are so low it has no effect so the truck would speed up instead of slowing.

[Chaoz2030]

Originally posted by Trucker_71:

@Elwenil I retired a few years ago from trucking after 45 years on the road, yup, I'm an ol' phart, but I could never explain the jake brake in such a detailed manner. Good job Elwenil. ;-)

Hey there driver! 45 years thats incredable. I only did it for a year but if I could find a local route that brought me home everyday and was decent pay id quit my job today and go back to trucking. I miss driving my KW.