the unnecessary usage of j-brakes, why????

A kenworth will actually turn the A/C on when you switch to defrost automatically. No way to turn it off.

 

If you run straight pipe, then yes. If your truck is like mine that is so quiet that you couldnt hear my jakes anyway, then I say no because jakes are not an expendable resource like brake shoes are.

I agree as well. i dont know about supposedly "helping" on quicker upshifts, but some people "claim" they can upshift better with the aid of the jake pullin the rpms down faster. I have yet to see it. Maybe I'm not doing it right, either. I dunno. Apparently Im not doing it right because the few times Ive tried it, it screws my shifting up more than helping.

 

It helps me when I skip gears but that's only empty since I have a 10 speed. However, we had an 18 speed auto that used the jake to shift whether it was on or not.

 

That's interesting.

Also, if I'm not mistaken, when in cruise control, doesn't the computer sense going down hill and engage the Jake automatically to maintain the set speed?
I've never been a big fan of cruise control use, and my right foot achieves better mpg results than running the cruise control does. So, once I determine what cruise can do, I switch it off and pedal it for comparison. If it does better than my right foot, I'd use it. But that's not the case, especially in mountainous conditions.

Yet, there are companies that insist that their drivers use cruise control the greater percentage of the time in the interest of fuel conservation, and will scold any driver(s) who fail to do so, for whatever reason, --- without crunching the numbers to determine if said driver(s) actually get better mpg's without using cruise.
It seems that professional desk drivers aren't inclined to listen to reason, just follow rules, even if the rules are counter-productive.

OH!

S hip
H igh
I n
T ransit

Don't confuse 'em with the facts. :smt104:smt102
That boggles their mind. :smt120:smt087

 

No, with all our supposed technological advancements, the cruise has no idea what's going on. It only sees the speed and/or rpm. My cruise is horrible. Kenworth calls it a soft cruise. I call it a stupid idea from someone with a soft head. It's pathetic how simple it would be to add in a gyro, an inclinometer, hell a gps device could tell it if it was rising or falling. But no, we get crap. It allows the speed to fall 3mph under whatever you set it at before it even starts winding the engine up, which takes another mph or so to produce power. On the other end, it won't kick the jake on until 4mph over and then only stage 2, which does nothing loaded. Horribly inefficient and annoying as hell. I wouldn't use mine either but my foot goes completely numb after a while.

 

It may not be that your not doing it right...could be your truck. Newer trucks tend to have a short delay in the jake engaging, so by the time your jake comes in your rpm's have already dropped. Also, drivers who shift with the jake tend to drive by ear, not the tach. Shifting with the jake does allow a faster shift...think about it...the faster you get your rpm's down, the sooner you can get it into gear. Now, not in every case, but in some cases it can allow you to gain a gear on a hill. One thing I would encourage any driver to do if they want to "truely" learn how to drive their truck is cover up the tach with a piece of paper and learn how to drive their truck. When you can shift without knowing how many rpm's your turning, your drivin a truck. And youll find that shifting with your jake will come much easier.

 

I personally run my Jake 98% of the time although I dont drive over the road I run locally. The Jake brake is a tool. A tool that give a driver more control of his or her vehicle. I try not to use it in residential areas but during working hours I will if the area is hilly. I live in Pittsburgh so it pretty hilly. Jake brake means control and its a lovely sound. It also means safety. Noone should have the right to tell me how to use my tool I use it when I need it.

 

I use my jakes 98% of the time as well, I run local in a front discharge concrete mixer. At 10 yards of concrete (aprox 33,000lbs depending on aggregate) plus a 35,000lb truck, fully loaded that's a lot of weight to have to stop at stop signs, cars cutting me off, people jumping into the road, quick change stop lights. So I just keep it on except when im empty then i'll turn it off.

 

Jakes produce up to 600 HP of stopping power. More than pulling.
In the engine setup options is the option for the engine brake on during cruise control...yes/no

Back to the fuel thing, Jake Brakes were invented in the early 60's. Long before an ECM was ever used. The fuel was mechanically controlled back then and fuel continued to be dumped in the cylinders when the Jakes were on. The old way stories has carried through to today as many other stories.

Jake on, Fuel off unless Jake is on Low, fuel will continue to half the cylinders.

 

That goes with all trucks and cars. The AC pulls the moisture out of the cab and aids defrosting. It has a negative effect if left on cold. Moisture gathers outside the windshield like you've noticed on rainy nights. Like an ice cold drink draws moisture on the outside.

Just add heat to it and it works great.