One in every five crashes on Queensland roads caused by tailgating

More than half of Queensland's drivers admit they get way too "up close and personal" with the rear of the car in front of them.

Tailgaters everywhere, bumping into each other with random abandon.

New research shows the dangerous behaviour is rife, causing one in five of all crashes.

Safety experts say the gap between vehicles should be two to three seconds but the study found 55 percent of drivers left a smaller gap.

Disturbingly the Queensland University of Technology study found more than four in ten drivers left a gap of less than a second. Bang!

The most common excuse for tailgating was so that other drivers weren't able to cut in or "queue jump".

"It shows rudeness and it can be intimidating for the driver in front, raising the risk of a serious crash," RACQ Safety expert Steve Spalding said.

"The driver tailgating has no understanding of why the driver in front might be going at a certain speed.

"It's often an issue at roadworks, where someone is trying to do the right thing only to have other motorists trying to push them along.''

Cue crash! Right on cue, this morning five cars went nose to tail on one of Brisbane's busiest thoroughfares, Milton Road.

It's just one of 5000 rear-end crashes that happen in Queensland each year.

The cost? Astronomical. The study found between 2000 and 2009 the social cost of rear-end collisions was $1.7 billion.

But get this: there's no sting in this tailgating tale.

None of the 500 drivers surveyed had ever been fined for tailgating, even though more than half admitted to doing so.

And 87 percent of the drivers reckon it's extremely unlikely they ever would be fined.

Tailgaters love a free ride.