Best drafting distance ?

I always stay back far enough to see the mirrors, which means that the driver can also see my car.
This will help keep you from being one of "those" Prius drivers that truckers like to jink their trailers to the right for when they pass a gravel driveway. Or.....they're also fond of making sure that their rear tires run over an 'interstate snake' (old retred tire piece on the road) giving you something nice to dodge on short notice.

I try to stay back a good bit further than the two or three seconds that the driver's manual says to (depending on the state), mostly because I don't like stone chips on the nose of my vehicle, and sometimes trucks will accidentally run over a piece of fod on the highway, and I can see crap like that a little bit further out if I don't have a big honkin trailer in front of me.

Your call.

 

If you can't see his mirrors, be passing, not drafting. If you are going to sit behind him, be visible to him.

And remember this handy chart
<--- passing side *** suicide --->

 

Never draft. This is a Prius, not a race car. You already get better mpg than most everyone else. If you really feel compelled to draft, get a CB and ask permission from the truck in front of you first, but are the risks worth the temporary one or two mpg bump? Your safety and others is more important.

 

Best distance about 1 inch. Seriously, Do not do it, you will save just a tiny bit, it is notworth while. Better youconcentrate on methods to improve you mpg by more thoughtful driving.

 

Even far enough back so he can see you,there will be better MPG.

 

I've said it in another thread, please don't draft trucks. As a 50 year tractor trailer driver I kind of know. A good truck driver knows you're drafting him and now has to drive for both himself and you. If the truck driver doesn't know you're drafting, trouble lies ahead as he/she hasn't been paying attention. Why put yourself and another driver in danger and/or make his job all the more difficult. Your C gets tremendous gas mileage (even at highway speeds) without the need to draft a fellow driver. I know because my C has just passed the 10,000 mile mark and has averaged 55.7 mpg. Who would have thought that a crusty old retired truck driver would be enjoying his C2 so much.

 

Drafting adds mpg and speed by healthy margins on track but on the street its extremely dangerous. The semi driver doesn't know you are there; and if he slows quickly you have to demonstrate razor sharp reflexes to avoid colliding. You may notice in NASCAR events the distance for drafting well is only a couple feet behind. Drafting has some good as far away as 20 feet front bumper to rear bumper butto be real useful its 2 feet or less. Thats on track.
I have drafted a semi at 5 to 10 feet whuile watching the instanteous mpg display on my Honda Civic hybrid and I could get almost double the mpg's, from typical 40 to 75 mpg. I had a trick: my son was driving the semi and we had CB's to comunicate so there was less danger.
drafting is worthwhile but only if you and the semi driver are communicating with CB's but don't count on it. Almost no semi driver wants a sbox trailing him at 10 feet and unseen.
So the answer is yes but don't do it unless you like repairing body damage - thats your prissy and/or you.

 

Best drafting distance? I'd say at least enough that you can come to a stop without running into the person you're following, with a margin for reaction time. Regardless of how fast they stop.

I'm just recalling: coming up to an intersection with lights, my light goes yellow, I decide to stop, it was by no means a panic stop, and in my rear view I see a harley fishtailing towards me. I take my foot OFF the brake, roll about 10 foot into the intersection, and he JUST manages to swerve by and run the light. And for my troubles his passenger gives me the finger. Good stuff.

 

I draft with my DRCC set to 1 bar or 100ft. If my mind drifts, the radar is still watching.

SAMSUNG-SGH-I747 ? 2

 

mpg vs safety....really! "Tailgaters" risk everyone's safety with poor judgement.

 

I dont think driving 100 feet behind a semi, is tailgateing. trucks often follow each other at less than this distance. trucks are heavy and because of inertia they cant stop fast like a light car. as long as their tail lights work it is fine. if break lights dont work then you could have a problem if your not paying attention.

if the truck has a blow out or kicks up a rock you will not have time to react. but you never have enough time to react to these things, they come at you fast. if you are in their path they will hit you and you just have time to duck.

think what you will but I think 100 feet is very safe, I prefer one truck length, aprox 60 feet. and behind a large motorhome that is pulling a car is best. the combination of motorhome and tow car seem to block all the air. I watched my mpg on camry hybrid climb way up to like 75 mpg going 65 mph. the road seemed flat. I still wonder if it may have been slight down hill.

remember "Safety third." The scale on this pic is way off. the trailer is only like 20-22 feet long, given the width is about 8 feet. Itt shows behind the truck 200 feet the entire truck trailer is about 35 feet and the distance behind the truck would be about 40 feet from truck bumper to the 200 feet mark.

all this said so you understand that following one truck length woulld be the bottom ot the pic. If the truck stops his truck as fast as he can. a light car with an alert driver can easily stop without running into the truck. If the truck was to run over somthing in the road you following at 1 truck length will likely have some issues ie " the dear he ran over you will also run over" thats a problem for your low clearence prius I guess not so much a safety problem as it could mess up your nice new car. rune your day! The other thing I find in following trucks is it kind of puts me to sleep. not really sleep but bored and I don't do it when I feel this way, you must have your attention on the truck ahead and traffic arround.

My opinions are not necessarly the opinions or views of this station.

 

Some trucks are heavy, some are very light, that all varies with the load of the day.

A new truck and trailer with good new brakes and great tires and a moderate load should be able to stop just as fast as your car. Can you tell from behind which trucks have good tires & brakes & moderate load, and which ones are overloaded with rotten brakes & tires? I can't.

And under certain circumstances, any truck will get stopped really short. I wish I could find the original overview picture of this five vehicle chain reaction accident near here, but these other pictures will have to do. I'll bet a case of beer that the last truck stopped shorter than your car can without 'frontal assistance':
Couple killed in I-90 crash identified
Star residents killed in crash near Snoqualmie Pass identified
I can think of several other similar cases, also on roads I frequent, but don't have time to find the pictures.

In the days of regular incandescent taillights on trucks, those brakes lights were often too dim (because of resistance from long wire runs and corroding couplings). The dimness was a double-whammy -- the filaments were slow to heat up to visible light, and the resulting dimness almost meant a longer recognition time. This very seriously diminished the available reaction time.

LED taillights have fixed this issue, but not all trailers have them yet.

I have already avoided a number of serious problems by leaving enough time to react. It is called 'defensive driving'.

 

The beauty of prii, mileage is good enough that you don't have to put yourself in harms way drafting another vehicle.
Lot's of people draft and I've always wondered why they have such a death wish, the word "lemmings" comes to mind.

 

I find it funny that one of the biggest complaints from Prius owners is being tailgated, and the biggest complaint about Prius drivers is going to slow relative to current traffic. Now you have this group that wants to tailgate Semi's and Motor Homes to get better MPG. Ask any Trucker out there what they think about cars riding their draft, especially a Prius.

This obsession with bragging rights for best MPG to the point of violating safety and disrupting traffic flow is wrong...period. Last time I looked the only factory stock car that beat Prius MPG was the first Gen Insight. Get over it.

 

The prius c stops in 118 feet from 60 mph, what truck stops in less than 200 feet? add the distance between the truck and your car you can stop easily before running into the truck you are following. If road conditions are special and allow a truck to have great traction and stop shorter than normal. the lighter car will also be on that same surface so it will still stop shorter.

I guess if the truck runs into something very heavy that is already stopped like another truck that is stopped in the road. then you may not have enough time to stop. I also stated you must be alert ready to break at any time. if you are not paying attention you could have a collision.

trucks often follow each other at less than 100 feet. this seems fine to them, law enforcement, and I dont here a lot of complaints about their death wish

you can leave lots of distance between yourself and other cars if you like. That makes sence but who determines how much. if roads are busy then that is difficult to do. If you follow at 2 truck lengths is that far enough. or 3.

really the big difference in following a truck or a car is you cant see what is in front of the truck. on a car you can see better and this helps anticipate what they may do.

My opinions and views are not necessarly the views of this station.

 

BRAKE.... FOR THE LOVE OF GOD!!!! BRAKE!!!! YOU WILL BREAK YOUR CAR IF YOU DON'T BRAKE!!!!

 

SAE published trailing and offset force and distance drafting data in 1971: Aerodynamics of Race Cars in Drafting and Passing Situations

That said, drafting is dangerous for the amateurs and poseurs thinking they can get away with it, as well as for drafted and surrounding traffic.