I remember seeing this certain movie, but all I can remember is a kid in a tanker truck , with a white liquid filling it up. Any help would be awesome.

Was the white liquid alive, and when people drank it they would become controlled?
So basically they kept trying to make everyone drink it. And the kid was hiding in the tanker, which they then started filling up to ship to white liquid to the next town.

That movie was called "The Stuff"
The Stuff (1985) - Plot summary

Hope that was it