Air suspension question
 

Bigger trucks and construction machines have a container with anti-freeze to stop corrosion and prevent ice in the systems for brakes and air suspension, and the air tanks needs to be drained regularly to get water out.

So, how does this work on a car with air suspension like the D3? It doesn't have the container with anti-freeze as far as I know and there isn't any manual drain valve for the air tank. Is there some kind of air dryer? Automatically drain valve? Tried to do some search online, but couldn't find anything useful...

Compressor has a small built in dryer as air volume is very small

Link below to a repair kit;

https://www.google.com/url?sa=t&rct=...ZfZWFB8XjyoN80

Ok, so this dryer is so effective that there is no need for a drain valve on the air tank?

If there are no leaks then the amount of air being pumped is very little, compressor comes on very rarely. On the truck with pneumatic brakes air is released every time you brake and fresh need to be pumped in.