A GMAC Insurance study announced today reveals that 130 million American drivers disregard the dangers of driving while fatigued. While 96 percent say they know it's as dangerous as driving drunk, 65 percent admit they'd drive seven hours or longer alone in one trip without significant breaks.

The news comes at a particularly dangerous time, as many people set off for longer road trips for the Fourth of July holiday, which is also the deadliest driving day of the year, according to the Insurance Institute of Highway Safety, based in Arlington, Va.

The GMAC Insurance study, which polled 5,175 licensed Americans from all 50 states and the District of Columbia, reports that 96 percent of drivers say they know that driving while tired is just as dangerous as driving while drunk.

July 3rd is the second deadliest day. Throughout the summer season, Americans will continue to add mileage on their odometers with longer road trips. The IIHS reports that more miles are traveled in August than any other month.

"Everybody has their own personal threshold, but we believe that driving seven hours without significant breaks is pushing the limit," said Gary Kusumi, a GMAC Insurance executive. "More than 100,000 crashes each year are caused by drivers falling asleep at the wheel."

It doesn't pay to skimp on sleep, and coffee and cat naps are only a quick fix. Getting plenty of rest is one of the keys to staying safe and being at your best.

Here are some tips to keep summer travel safe, fun, and full of great memories:

• Plan ahead. The best way to make sure you're alert? Get proper rest ahead of time before setting off on your road trip.

• Avoid alcohol. Even the tiniest amount of alcohol can make you drowsy. If you'll be driving, avoid it altogether.

• If possible, take a buddy along on long trips, so you can take turns driving.

• Avoid driving between midnight and 6 a.m., when you're most likely to feel fatigued.

• If you feel drowsy, the safest thing to do is to pull over and stop driving. As soon as possible, drive to the closest safe resting spot, such as a motel or a friend's house, and catch up on your sleep.

The study was administered by TNS, a market information resource and provider of custom research and analysis. The national sample was comprised of 5,175 total licensed respondents, aged 16-60 and over.