why dont trucks have turn signal canceling?

Because you are supposed to be a professional driver who is aware that he turned his blinkers on in the first place and know how and when to turn them off.

Actually, there's never been any demand for them on trucks or the manufacturers would have installed them. They aren't that complicated an item to make and install. For many years, until relatively recently, the actuator for the blinkers were't integral to the steering column, but were added on afterwards as a bolt on component. Being just added on, there was no mechanism to operate the self cancelling features.

 

I thought it was so it would not turn off before you made a turn. I know in my car I have started a turn and the signal turns off before I make the turn. Cool thanks for the lesson

 

you got it

 

Yep, you are right, imagine this scenario........A semi in the right lane on a 2 lane road, needs to turn right and signals to do so in plenty of time, has to swing out into the left lane to make the turn and the signal self cancels, mr ignorant/not paying attention in the 4 wheeler behind see's no signal and/or thinks semi driver changed his mind................
result, a 2ft high 4 wheeler and possibly a fatality

 

dang and i thought my signal cancel thing was broke

 

I wish the manufacturers would make it where your headlights would come on if your wipers are on. I know they can do it, I have a Chevy Tahoe that can sense rain and determine wiper speed. This needs to be for ALL vehicles.

 

Imagine, if you will, sitting in your parking spot & you hit the washer while parked.
Your headlights flash on & off a couple times.
You're likely to have some unwanted company knocking on your doors.

 

They wouldn't come on that quick. You could have a time delay. I'm not an engineer, it was just an idea.