<p>No road trip is complete without a soundtrack, and your old head unit might be woefully unprepared to keep you entertained as you eat up mile after mile of pavement. A complete overhaul of your sound system might not be in the cards, but great sound starts with a great head unit.</p><p>If you’re going on a long cross-country road trip, you might even want to upgrade to a <a href="https://www.lifewire.com/what-is-satellite-radio-534582" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">satellite radio</a> unit. Or you can just buy a modular receiver. It’s a lot easier than burning hundreds of CDs, and you’ll be able to listen to the same stations wherever your road trip takes you.</p><p>Some head units, like Sony&#39;s GS series MEXGS810BH pictured to the left, allow you to add Bluetooth, HD Radio, and satellite radio to your car all at once.</p>If you have passengers to keep entertained, a video head unit will keep them from incessantly asking if you’re there yet. These devices used to be priced right out of most budgets, but there are plenty of affordable video head units these days if you’re willing to sacrifice a little on features.A lot of video head units have auxiliary outputs, so you might as well take advantage of them. Auxiliary LCDs can be mounted just about anywhere, but one of the most convenient options is to buy replacement headrests that have built-in screens. The screens can be hooked into your head unit, but you can also connect them to a video game system, external DVD player, or any other video device.In case you don’t want to tear out your head unit, you can still provide DVD entertainment to your passengers. Ceiling-mounted external DVD players often have flip-down LCD panels that can be viewed by everyone in the back end of your car or SUV. You can also find combo DVD/LCD units that are built into replacement headrests and units that can be strapped to your existing headrests.<p>There’s a sort of visceral pleasure in unfolding a map and plotting a course, but the novelty factor wears off pretty fast when you’re speeding down the freeway and need to look something up. If your car didn’t come with a built-in <a href="https://www.lifewire.com/choosing-a-car-gps-unit-534733" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">GPS navigation</a> unit, some replacement head units include that option.</p><p>On the other hand, there are plenty of modular GPS devices that you can just grab and take with you in any vehicle. Many GPS devices even include points of interest like gas stations, restaurants, and lodgings.</p><p>The price of gas is enough to give anyone pause when reaching for the air conditioning controls, but there aren’t a lot of other options. Rolling the window down doesn’t always do the trick, and the days of <a href="https://www.lifewire.com/what-is-a-swamp-cooler-534715" data-component="link" data-source="inlineLink" data-type="internalLink" data-ordinal="1">window-mounted swamp coolers</a> are pretty much gone. If you can find a vintage swamp cooler, it might be just what you need to cool off on a hot, summer road trip.</p><p> </p><p>However, you might also want to look into a handheld unit. Battery-powered evaporative coolers aren’t as powerful as the old window-mounted swamp coolers, but they’re far more portable.</p>When the asphalt seems to be melting all around your car, nothing hits the spot like a frosty beverage. A 12 volt cooler can keep your water, sodas, and snacks cool while you’re on the road. An ice chest will also do the trick, but then you’re stuck dumping and refilling it every time the ice melts.<p>If you have more 12 volt accessories than outlets, a power splitter will let you keep your GPS and phone plugged in while the kids charge their DVD players and game systems. Just make sure that you don’t overtax the circuit with an excessively large current load.</p><p>In addition to splitting one cigarette lighter socket into several 12 volt accessory sockets, some splitters also include one or more powered USB connectors that you can use to directly power cellphones, tablets, and other devices.</p><p>Power inverters are essential if you want to use any AC-powered gear on the road, but they come in a couple different configurations. Some of them are safe for use with delicate electronics and others don’t play nice with certain devices.</p><p>You can also choose between models that plug into your cigarette lighter and others that have to be wired directly into the electrical system. You’ll need to go with the latter if you have any serious power needs, but be careful not to overtax your alternator.</p><p>Some inverters, like the BESTEK model pictured to the left, include both cigarette lighter and battery connections and also provide the option of plugging in USB cables to power devices like phones and tablets.</p><p>When trouble strikes on the road, help is usually just a phone call away. However, it never hurts to be prepared. Your cellphone might go dead, or you might find yourself in an area without service. In those cases, you’ll be extremely happy that you decided to pack a jump box.</p><p>Some jump boxes just include a gel pack battery and jumper cables, and other models include lights, radios, sirens and tire pumps, among other features. You can even find jump boxes that include built-in inverters, which allow you to plug in your AC devices.</p>Nothing can bring a road trip to a screeching halt like a flat tire, which is why a tire pressure monitoring system might just be the most crucial piece of road trip tech you ever buy. These systems include a sensor and transmitter for each tire, so you remain apprised of the pressure in all of your tires. If the pressure dips, you’ll be able to take action before you get into a dangerous situation.