Question For Downhill Driving With An Automatic?

My truck is like this, when the engine break is on break lights are on for truck and trailer. 2017 10 speed pete.

Thanks for the clarification on that. They may very we activate on my 2019 Cascadia too. I may need to jump out when going down hill and run behind and check!!

You can check this as you drive past a big road sign at night. Check for the reflection in your mirror.

My truck is like this, when the engine break is on break lights are on for truck and trailer. 2017 10 speed pete.

Thanks for the clarification on that. They may very we activate on my 2019 Cascadia too. I may need to jump out when going down hill and run behind and check!!

Might be safer to just turn your jake on at night and look at your driver side mirror, but you do you bro.

If my truck was going uphill and stopped, I probably wouldn't be able to jump out, check, and catch up to it again. Lol! If your brake lights LEGALLY have to come on with the service brakes, then if you slow down with the jake brake, wouldn't it be required that the brake lights come on? Brake lights are there to let traffic behind you know you are slowing down, why not when you are using the jake to slow down?

On my 2016 Peterbilt the brake lights DO NOT come on when the jake is active. The early 2018 Peterbilt I did my team training in did however.

For me on down grades, it's highly dependent on several factors. How heavy am I? Slow speed limits? Lots of curves? And lastly, but certainly the most important, what grade am I dealing with?

I'll use east bound Montana I-80 Homestake pass as an example with 79,000 lbs. 7th gear all the way up. First crest I'll go to 9th. Second crest is where it gets interesting. Down to 7th through the twisties then 8th for the last few. After the last curve I'll go to 9th to the bottom.

Used that pass because it has speed limits for trucks and it is rather technical. 25 mph at the top then goes to 35 mph then 45 mph back to 65 mph.

If my truck was going uphill and stopped, I probably wouldn't be able to jump out, check, and catch up to it again. Lol! If your brake lights LEGALLY have to come on with the service brakes, then if you slow down with the jake brake, wouldn't it be required that the brake lights come on? Brake lights are there to let traffic behind you know you are slowing down, why not when you are using the jake to slow down?

We're talking about a government run regulation here, so you're guess is as good as mine on that one. I'm guessing because like everything else the material is not always updated as the industry changes, but instead is updated several years after the industry has changed. That and jake brakes are used to hold speed not decrease it on mountains? Or at least that is how I use mine, I usually set gear and jake brake so that the truck will maintain a certain speed going down the grade so I don't have to use my service breaks much or at all. I also know my pete wants me to use the jake to slow down instead of using service brakes which does make sense as far as wear and tear on the brakes is concerned.

Doesn’t come on on the cascadia unless it’s the computer applying braking. If you just throw the jake on, the lights won’t come on. I put the tranny in a manual gear, jake starting at setting 1, and let gravity do the rest. That way I can supplement with service brakes at will. I also put my hazards on and go as slow as I’m comfortable with. My 2016 cascadia jake setting 1 seemed to be more effective than the 2019. Sometimes I drop the jake to higher settings if needed. Remember you can go down too slow as many times as you want, but you might go down too fast only once.