How do I stop cars from tailgating?
I have a method which works well and/but which I use only in circumstances where it seems likely to reduce and not increase the all round risk. I've used it more on large trucks than cars.
Why do it:
If it makes good sense to let the tailgater go I would generally do so.
This may not be the case in some traffic situations where the tailgater is dangerously close if a stop is required and allowing overtaking is not a good immediate option. Reasons for this can arise for a range of reasosns but two typical situations are if allowing overtaking may
increase the danger as they overtake (some mix of: tight winding road, low visibility, wet, no overtaking lines, ...)
create a situation where my overall 'quality of travel' would be severely degraded with no or vastly less gain (eg stock transporter streaming effluent in a high traffic country road situation - if he overtakes me he is then trapped in front of me and I get splattered with cattle excrement for many miles - dangerous as well as unpleasant.
Warning: Bear in mind in the following situations that a large laden truck may weigh 40 tons and probably mote than 20, and has a stopping distance better than ocean liners and freight trains but much much much worse than for cars. The action should be taken to try to reduce the chance of deathy not to increase it.
Ease very gently back on throttle to close gap between you and tailgater and, "until you are certain that you have their attention". ie there WILL come a point where they must be aware that the gap is closing towards zero. You are hardly if at all in any more danger at this point as an accident was almost certain in the prior case in the event of a sudden stop.
Then continue to slowly lower your roadspeed and open the gap between you and the vehicle ahead of you. The vehicle behind you has no realistic option but to maintain minimum gp and lower speed. An utter idiot / drunk / man on a mission may make vehicle to vehicle contact, but this is extremely unlikely, and you might as well find out about him now with some degree of control, than later by mistake.
When an "adequate" gap has opened up in front of you accelerate "very crisply" and then brake very visibly (good long burst of brakelights) to arrive at and maintain a safe following distance behind the car in front of you.
The tailgater is now well clear of you, you are at safe speed and distance from the car in front and the tail gater is travelling below queue speed. They can choose to adapt, to now maintain a safe distance, or may "as sometimes happens" accelerate aggressively and get back 'on your tail'. You can repeat the procedure above multiple times and they cannot prevent you doing so BUT odds are that 2 or 3 times max is the most that is useful. It it has not worked after a few applications a modified version will work, one way or another.
Drop back as before and stay back. If possible and useful make it possible for them to overtake safely. If they do not overtake and do not increase the following gap you can maintain a following distance that is enough for both of you in an emergency.
Occasions where I would try not to allow them to overtake might be the "stock truck" situation where they cannot go anywhere once they have passed and will then be splattering excrement all over your car indefinitely. In such cases you can generally control the speed and location of the following vehicle. If they are so aggressive as to continue to threaten your life repeatedly then a record of their number plate and a subsequent telephone call may help prevent others being similarly threatened. Large heavily laden trucks generally cannot realistically overtake in such situations if not 'allowed to'.
Again - the aim is to improve safety and reduce risk overall. If you can realistically let them go then doing so will often be the best choice.