How to manage/control different calibration values for different truck models at end of line manufacturing?

Thread Starter


Joined Jan 4, 2017
We have hydraulic steering system with small motor atop it.

This system will be mounted in about Five truck models. All truck models will have same steering software but different values for calibration parameters. Supplier will deliver steering ECUs to OEM manufacturing with steering software and calibration parameters programmed in the ECU.

For any reason, if we need to adjust calibration parameters at End of Line, we need to find a way to manage or control different calibration values for different vehicle models. For example, at end of line, parameters must be re-programmed in the truck they are intended for. what are some options for managing this?


Joined Jul 10, 2017
You should be asking the suppliers this question. We have no idea what hardware, firmware or software is in the control unit or how it is re-programmed or updated so I am unable to offer any help.
Normally those functions will be integrated into the OEM software used to connect with the vehicle for diagnostic and programming purposes. As already mentioned you need to ask the supplier about this sort of information. They are the ones who designed it and know how it wold work.


Joined Sep 30, 2009
From his postings over at ETO he seems to be representing the manufacturer. He asks many questions about big trucks and how to get things done at end of manufacture. Stuff like brakes and steering.
Honestly I would be a bit afraid to buy a vehicle from a manufacturer that is asking how to get things done on the internet. I can appreciate that some areas of the world may not be at the same level of technology and such that I am accustomed to, but at the same time the best people to ask are the people you deal with... not random strangers online.


Joined Sep 30, 2009
Over at ETO he didn't even know that caster in a front spindle is what caused the wheels to center themselves after a turn. He wondered how to program his power steering box to force the wheels into being pointed straight again.


Joined Jan 8, 2017
The way the question was posted with no information about the product makes me think the TS knows nothing about the product so he should not be attempting to fit is to a truck.

Over at ETO he didn't even know that caster in a front spindle is what caused the wheels to center themselves after a turn.
I never picked up on that before. It makes sense though.

Honestly I think the TS is just trying to learn, but maybe doesn't have enough of the right background to ask the right questions. Unfortunately even with the right questions there are too many variables to account for, too many different ways of doing it, and too many parts available to just guess at a solution.

I know at my previous job we started to see what looked like servo motors attached to the steering gearbox. It may have been some sort of stepper also, but my factory experience tells me they at least had some sort of encoder built in ... it wasn't a factory authorized shop so we didn't have the details. Most people there just loaded the parts cannon anyways and I finally had enough of watching people spend $1000 to fix a $2 problem. Long story short there really shouldn't be any calibration that needs changed at end of line. Everything is keyed so it will only go together one way. Any centering adjustment would be made at the drag link and tie rod ends. Other than that the ECU should already be programmed correctly if you are running an efficient factory.