Added Lane Sign (W4-3)
The added lane sign is a diamond and its colour is yellow. It is a warning sign: something ahead — a curve, a crossing, a change in the road — needs you to slow down and adjust what you are doing.
At a glance
| Shape | diamond |
|---|---|
| Color | yellow |
| Category | Warning signs |
| MUTCD code | W4-3 |
How the test asks about it
- 1.
How does this sign differ from a merge sign?
Not quiteCorrect answer: C — Traffic joins into its own new lane, so no merging is required
An added lane means the joining roadway gets its own lane. Nobody has to yield or change lanes, which is exactly why an unnecessary merge here causes conflict.
Drivers who treat an added lane as a merge brake or swerve for traffic that was never going to enter their lane.
- 2.
How does the condition this sign warns of differ from a merge?
Not quiteCorrect answer: C — The joining road becomes an extra lane, so neither stream has to give up its lane position
With an added lane the entering roadway continues as a lane of its own instead of feeding into yours, so vehicles join without anyone having to yield. Keep watching it anyway, because an added lane often ends further along and then a real merge does happen.
Swinging left to make room as if it were a merge, which puts you into a lane you never checked. With an added lane you can simply hold your position.
Related signs
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