Is a center brake light required in the US?

3rd brake lamps, the centre lamp, is required by federal law in the US and Canada since 1986 for cars, and since 1994 for light trucks and vans.

There may be some vehicles with exemptions. You don't say what kind of truck you have that doesn't have the light, but I can't think of any current models of any delivery van that would be exempt..

Many trucks have the light on the trailing edge of the roof.

Edit Nov 2:

I was really hoping you would put the make and model in the post so I could look it up.

It is put on all new vehicles. You may be seeing an older truck before they were put on. Like pretty much anything else it isn't required to install if it isn't factory original equipment.

The center brake light is *not* required by State Law. See California: http://www.leginfo.ca.gov/cgi-bin/displaycode?sect...

FMVSS 108 shows what lights may be *SOLD* --http://edocket.access.gpo.gov/cfr_2004/octqtr/49cf...

Have fun reading.

If factory equipped, they are required.