Dump truck PTO stops raising box when my foot is on the brake

Hi would anyone know why the PTO would stop raising the box when foot is on the brake . It works fine with the parking brake applied.

 

What year truck and what kind of pto? Either spool valve is sticking or it’s got some kind of nanny system in it to stop it if it’s not stopped

 

Thank you for responding I will definitely check what you mentioned. Its a 2020 peterbilt 567 super tag dump truck. Not sure about the kind of pto but it came equipped from the factory. It has eaton automatic transmission. I bought the truck used with 170k miles .

 

If it’s factory and an automatic I’m going to say it has some kind of nanny system on it to prevent it from dumping without the brakes on

 

Something seems off. I don't see how you could do asphalt without being able to feather the brake and spreading gravel would be a PITA with an auto that you couldn't feather the brake.

 

Hahaha you already know the struggle man but I'm making it work. My mechanic said there could be a setting on the engine which prevents it from working with the brake. For that I would have to find someone with a computer to connect and see if thats the case.

 

Hit the throttle while holding the brake

 

You have to throttle up to use the pto with your foot on the brake.I’ve got a 2020 Pete 567 with auto trans and do asphalt and all types of work with it. Your truck should be in neutral, it won’t work in a drive gear

 

Hello im having the same issue. I know throttling works but is there a way to bypass the nanny system? Thank you

 

I've learned to live with it.
But it is posible you're gonna have to change parameters on the ECM.