What's the one single car part you don't understand on your car?

We need engineering explained right about now

Why they sell Blinker fluid in 0.5l cans if my car only uses 0.3l.

Engineering Explained be like
https://s-media-cache-ak0.pinimg.com/564x/bd/71/f0/bd71f076731d3e8450e6496e0d46c7aa.jpg

But to be honest i don’t get vacuum system. i don’t get it how it works or why we need it in a car.

I drive a BMW, and I don’t understand that lever on the left side of the steering column, like why is it there?

Myself, i dunno why i chose slime green for my 200sx

How exactly does a posi-trax on a Plymouth work? …. it just does.
A cookie to who knows what movie that’s from.

Indicator stalks on a BMW…

Blinker fluid, I let it run out and still don’t understand what has changed

i assume a helical differential performs the same job as a normal differential. The reason they use helical gears though is because they can take more force through a smaller size of gear. this works well for weight reduction and space that is avaliable. This works due to having a larger surface area between the teeth in contact while the gears are spinning. This spreads out the load (force) across the surface of tooth rather than on to a single point. Hope this helps a little bit.