Braking while Backing
Posted by Ok_Difficulty_6906@reddit | Truckers | View on Reddit | 40 comments
Hi guys I’m very new to trucking. I’m doing pretty good with everything except for braking while backing. Most of the time I run the air out of my brakes and I have poor control of the pressure on the pedal. I will have the pressure at 11psi while in drive, and I won’t move my foot at all but as soon as I put it in reverse it shoots up to 55psi. As I’m backing, I’ll slowly release pressure off the pedal but my air “pumps” out pretty fast. What adjustments do I need to make? I’m trying very hard to be mindful about the pressure on the brakes but I’m starting to get frustrated (my trainer is too lol). Please help me out. Has anyone else had this issue?
threeglude@reddit
Op, what is the exact truck you're driving? Ie, year, make, model and transmission type (auto or manual).
Believe it or not, the truck info is critical in order for people on the internet to have even the slightest chance of providing helpful tips/tricks.
Ok_Difficulty_6906@reddit (OP)
It’s a 2025 Peterbilt an automatic. Also I don’t use the accelerator while backing.
threeglude@reddit
Also, are you using the accelerator in reverse? Because as a complete green horn, you really should stay of the accelerator pedal while in reverse. To use the hammer when in reverse requires the driver to either be a natural, and or, be at an intermediate- expert level backing skills.
Redsoxdragon@reddit
Are you driving an auto or a manual?
Either way, it's more of an acceleration control than the brakes. You shouldn't have to gas it when backing up, the truck will roll on its own unless you got one of those awful trash ass lurchy autos.
If you got a manual, just fiddle with the clutch and only press the brakes when you need to stop.
Also personal tip, adjust the way you lay your foot on the accelerator. If you keep it lower down, your big toe will have more finesse than of you were too flop your ankle
Ok_Difficulty_6906@reddit (OP)
I drive an automatic and thank you! 😊
cdubose@reddit
Is it an automatic Cascadia? If so, that's probably the problem. Even with creep mode off those things run out of air immediately if you don't back like perfectly and have to keep pulling up and trying again. I'm in a Kenworth now and never have that issue.
mxadema@reddit
When backing you can control your speed just with the clutch, you are not going fast enough to need a lot of brake. Also if you do need some, just the weight of your foot is enought.
It does take a bit of time to get good at backing, but take it slow. Just clutch in and out, let it roll, no need for big brake application.
SafariJim@reddit
If you have a newer kenworth apparently its a design thing. Ive talked with many other drivers with them and they all say the same thing of the brakes releasing too much air when backing.
Sabre_Stryke@reddit
I started turning off Hill Assist when I back. Fixed the problem.
HowlingWolven@reddit
Turn off your hill assist and get used to letting it roll. Don’t brake drag.
SheepherderHopeful55@reddit
Do you drive an International Pro Star? If you it's not a you problem it's a truck problem, the air tanks on those trucks are very small and it is a common problem
anxious_polarbear@reddit
Sure nothing is leaking?
Ok_Difficulty_6906@reddit (OP)
No leaks! My trainer backs it just fine without the brakes running out of air. It’s a skill issue on my end lol.
anxious_polarbear@reddit
Do you modulate your foot (push, release, push, release)?
Ok_Difficulty_6906@reddit (OP)
No I don’t maybe that’s the problem
anxious_polarbear@reddit
No, modulating is what will bleed air off. You want to keep a steady foot.
Environmental-Pear40@reddit
Oh yeah, new guys tend to do that. You should be holding light pressure on the brakes unless you're pressing the accelerator or coasting. You don't want to press and release a lot.
Kind of have to in a cascadia since that's how you stay in creep mode, 🙄, Pos truck. Freightliner could never consider a situation where a truck might want to slightly accelerate while backing.
LordRaven74@reddit
I assume you have an automatic. Is it a 10 speed or a 12 speed. If it is a 10 speed, they are notoriously under powered in reverse. If it is a 12 speed, it is a computer issue and you can have your shop make adjustments. I drive a 12 speed and it has enough torque in the reverse gear that it walks back by itself.
Environmental-Pear40@reddit
It's at 12 speed automatic. The problem is that it doesn't like to stay in creep. I've kind of figured out how to work around it though. Just annoying when I have to back uphill to a dock.
LordRaven74@reddit
You should have a conversation with your shop. It sounds like the torque is turned down.
Environmental-Pear40@reddit
Yeah this truck is definitely underpowered but I'm also leaving the company so.
LordRaven74@reddit
Soon to not be your problem. Good man. Best of luck to you at your next company
Ok_Difficulty_6906@reddit (OP)
Thank you. Any other tips for me?
InevitableCoast7279@reddit
Check if your foot position changes when you shift to reverse - maybe you're unconsciously pressing harder because backing makes you tense up. I had similar issue with my car when I was learning, turned out I was gripping steering wheel tighter and pressing everything harder without realizing
Odd-Fuel-9002@reddit
Try backing using as little throttle as possible. If you don’t get going too fast in the first place then you shouldn’t need to use the brakes very much unless you’re going downhill. I wouldn’t stress it too much you will get better with time and develop a feel for it. Just concentrate on good set ups, not hitting anything and use GOAL.
Kiklanisune@reddit
Is it that stupid hill assist ? The Volvo i have now and westernstar I had prior both had ridiculously sensitive hill assist and it loves to engage while backing
Kiklanisune@reddit
Your trainer is likely barely using the brakes and creep mode stay enabled. If you brake a bit harder it will disengage and if the grade is 0.001% it'll engage the hill assist if you come near a stop or stop.
Someone called it the cascadia queef and honestly I laughed every time I forget to turn the hill assist start off now.
BB5er@reddit
I assume it’s an automatic. Either way, lower your idle down before backing up, then learn to stay off the brakes until you are in tight quarters. It’s 20% a problem with automated transmissions sucking up too much air pressure, and 80 percent your lack of confidence.
Ok_Bug_6470@reddit
Gently but automatic compressors absolutely are freaking horrible horrible horrible. Backing an automatic is horrible and isn’t as controllable as a standard. I know you’re supposed to be able to no erode it but the compressor situation is laughable. It is the standard now so you’ll have to get better at it but normal backing you shouldn’t be losing that much air. He might need to fix something on the truck too and he’s just cheap and blaming you.
kali4niakid@reddit
Don’t hit the brakes, gently apply pressure
Rough-Method8876@reddit
As for the spiking to 55psi? This can be adjusted by readjusting your brakes/slack adjusters. When I was new…what feels like a very very long time ago…they actually adjusted the brakes out so that I could get a feel for it. When I had everything else figured out, we slowly tightened them back up to be hair pin triggered like yours do.
As for the high level of air being released and you losing tank psi? Most common places in my opinion are at the glad hands (blue service side), foot brake valve (this is actually where I’ve had the most struggles over my years with something like this. It’s a real pain in the ass to replace depending on your make/model), or under the trailer a problem with a brake chamber diaphragm. Not saying this is an end all be all list…as your make/model has some to do with this too.
Environmental-Pear40@reddit
Really not sure what you're talking about. I think it's applied breaking pressure. Which really just shouldn't be paying attention to unless you're having a mechanical issue. There's nothing I can think of that would cause a spike in braking pressure other than operator error. Majority of the time I only pay attention to breaking pressure if I suspect a service side leak.
Ok_Difficulty_6906@reddit (OP)
Is there a certain way I need to adjust my foot to have better control with my pressure on the brakes?
Environmental-Pear40@reddit
I really couldn't tell you without a ride along. It's all subconscious to me. Maybe you're hyper fixating on pressure? Try to ignore the gauge.
Personally when I'm backing I switch between breaking and accelerator all the time. I never look at the pressure gauge. Perhaps you are a little rough on the brakes but the only thing that would fix that is experience. Don't try to aim for any magic number on applied pressure, make it an instinct. In most trucks you can also raise the idle which will help with air loss.
I think I had a similar issue where while backing. Because the idle was so low I would lose pressure with braking that was in a KW and the way I dealt with it was raising the idle up to around 750-800. It also helped with the steering.
threeglude@reddit
Bad idea for a noob already having trouble. Raising the idle will increase the trucks max ground speed at idle as well, op would feel even more our of control.
Environmental-Pear40@reddit
I mean, It shouldn't be too bad in r1. Sounded like the issue is with air pressure. But yeah, it would be a bit quicker. Not as bad as the r2 prank, though.
threeglude@reddit
It was years ago, but I remember several fellow green horns in my CDL school have difficulty with backing, and it was almost always, 1 of 2 things, sometimes both.
Sounds to me op is one of those where backing doesn't come naturally and he's struggling with it. Speed, even an extra 1/2 mile/hr will fuck with his/her backing process.
Environmental-Pear40@reddit
Fair enough, I'm also leaning towards the "they're overthinking it" side of things. But I also remember that I had an issue sort of similar with a KW. It wanted to idle at 600. I didn't exactly raise the idle because of the air pressure not charging fast enough I did it to make the steering easier on my bad shoulder but that was a benefit.
RoamingNomadSoul@reddit
I have a freighliner and they have something called creep mode. You step on the brakes once and it slowly reverses on its own. You are braking a lot because you are going too fast
Freightshaker000@reddit
If you put the corner of the brake pedal near the ball of your foot, you'll have a better feel for it, and better control.