Exit-Only Lane, a Tailgating Truck, and a Low Fuel Light
You are eastbound on I-80, a three-lane interstate, at 65 mph at night. Your fuel light just came on. A green guide sign reads 'Exit 14B - 1/2 MILE' with an arrow pointing to the right lane. A blue service sign says 'Gas - Next Exit.' A mile marker '14' is visible on the right shoulder. You are in the middle lane. The right lane is an exit-only lane and is backed up with brake lights. A tractor-trailer is close behind you in the middle lane, and your GPS says 'keep left for 2 miles.' You need gas, but you are not sure whether 'Next Exit' means 14B or a later exit. What do you do?
1. How should you interpret the exit-only lane and the service sign, and what lane should you choose?
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The right lane is exit-only: once you enter it, you must take Exit 14B. The service sign 'Gas - Next Exit' is a guide sign for services at the next interchange, which in this case is 14B; it is not a promise that gas is at a later exit. Because your fuel light is on and you may not have range to gamble, the safer choice is to take 14B. Move right early, signal, and merge into the exit lane behind the queued traffic rather than cutting in at the gore. If you decide to wait, you must accept the risk of running out; do not stop on the shoulder to check the GPS.
2. The tractor-trailer is tailgating you. How does that change your lane change?
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A tailgater compresses your margin. Do not brake hard or make a sudden move to the exit lane. Signal early, slow gradually, and let the truck's driver see your intention. If the truck is too close for a safe merge, continue to the exit and take the next legal opportunity rather than forcing a gap. On a multi-lane interstate, you can also adjust speed slightly to create space behind you before changing lanes. The key is to avoid a panic lane change at the gore point, which causes many last-minute crashes.
3. How do interstate numbering and mile markers help you confirm the exit?
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I-80 is an even-numbered interstate, so it runs generally east-west; mile markers and exit numbers increase as you travel east in most states. The mile marker '14' and 'Exit 14B' line up, so the exit is about half a mile ahead. The 'B' suffix means a second exit or split at the same interchange, so you should read the guide sign carefully. Route marker conventions are aids, not a substitute for the actual sign: follow the green guide sign and the exit-only arrow. If the GPS contradicts the sign, the posted sign and pavement markings control.