# Trucks hauling three trailers: is this a new thing, or am I really unobservant? **URL:** \ **Category:** Factual Questions\ **Created:** [April 9, 2008, 7:55pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653 "2008-04-09T19:55:11Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![mlerose](https://avatars.discourse-cdn.com/v4/letter/m/43a26b/32.png) [@mlerose](https://boards.straightdope.com/u/mlerose)\ **Post date:** [April 9, 2008, 7:55pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/1 "2008-04-09T19:55:11Z")
The superhero and I just completed a two-week road trip to California and back, during which time we got hitched. Hooray! Anyhow, we took I-80 out to the Bay Area and drove down 5 to LA, took 15 through Vegas, and up to I-70 to get home. Both of us noticed many, many commercial trucks hauling three trailers. I don’t recall ever seeing trucks hauling more than two before. Is this a new phenomenon (perhaps because of rising fuel prices?) or is it something that’s been going on for quite some time, and I just never noticed until we were surrounded by big trucks for days? Thanks! ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [April 9, 2008, 8:02pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/2 "2008-04-09T20:02:14Z")
They’ve been around for many years. > **[Semi-trailer truck](https://en.wikipedia.org/wiki/Semi-trailer_truck)** > > A semi-trailer truck (also known by a wide variety of other terms – see below) is the combination of a tractor unit and one or more semi-trailers to carry freight. A semi-trailer attaches to the tractor with a type of hitch called a fifth wheel. Semi-trailer trucks replaced traction engines in commercial and heavy haulage roles. This transition occurred primarily between the 1920s and 1950s, driven by the need for greater efficiency, speed, and reliability. > There are a wide variety of Englis... > [@](#): > > The United States also allows 2-axle tractors to tow two 1-axle 28.5-foot (8.7 m) semi-trailers known officially as STAA doubles and colloquially as doubles, a set, or a set of joints on all highways that are part of the National Network. The second trailer in a set of doubles uses a converter gear, also known as a con-gear. This apparatus supports the front half of the second trailer. Individual states may further allow longer vehicles (known as “longer combination vehicles” or LCVs), and may allow them to operate on roads other than those part of the National Network. > > LCV types include: > > Triples: Three 28.5-foot (8.7 m) trailers; maximum weight up to 129,000 pounds (58.5 t). > Turnpike Doubles: Two 48-foot (14.6 m) trailers; maximum weight up to 147,000 pounds (66.7 t) > Rocky Mountain Doubles: One 40-foot (12.2 m) trailer and one 28.5-foot (8.7 m) trailer (known as a “pup”); maximum weight up to 129,000 pounds (58.5 t) > In Canada, a Turnpike Double is two 53-foot trailers and a Rocky Mountain Double is a 50-foot trailer with 24-foot “pup” > Regulations on LCVs vary widely from state to state. No state allows more than three trailers without a special permit. Reasons for limiting the legal trailer configurations include both safety concerns and the impracticality of designing and constructing roads that can accommodate the larger wheelbase of these vehicles and the larger minimum turning radii associated with them. > > Most states restrict operation of larger tandem trailer setups such as triple units, the “Turnpike Double” (twin 48-53 ft units) or the “Rocky Mountain Double.” (A full 48-53 ft unit and a shorter 28 ft unit) In general, these types of setups are restricted to tolled turnpikes such as I-80 through Ohio and Indiana, and select Western states. Contrary to the former article written on this topic, tandem setups are not restricted to certain roads anymore than a single setup. The exception are the units listed above. They are also not restricted because of weather or “difficulty” of operation. As noted, they are banned in many parts of the country, so if you’re not used to driving where they are legal, it’s easy to be surprised by them. ---
**Author:** ![mwbrooks](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@mwbrooks](https://boards.straightdope.com/u/mwbrooks)\ **Post date:** [April 9, 2008, 8:22pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/3 "2008-04-09T20:22:07Z")
[QUOTE=Exapno Mapcase] As noted, they are banned in many parts of the country, so if you’re not used to driving where they are legal, it’s easy to be surprised by them. [/QUOTE] Especially when you’re on a two lane road with steep shoulders, out on the bare face of the Earth in Nevada somewhere, and you see what you think is one oncoming truck trying to pass another in your lane, then realize it’s actually just a single truck whose third trailer being pushed over into your lane by a stiff crosswind. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [April 10, 2008, 1:39am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/4 "2008-04-10T01:39:05Z")
They’ve been around Australia for a long time. > **[Lycos.com](https://www.lycos.co.uk/)** > > Lycos, Inc., is a web search engine and web portal established in 1994, spun out of Carnegie Mellon University. Lycos also encompasses a network of email, webhosting, social networking, and entertainment websites. Of course we don’t stop at just three trailers. [![](https://upload.wikimedia.org/wikipedia/commons/thumb/d/df/Road_Train_Australia.jpg/800px-Road_Train_Australia.jpg) ](https://upload.wikimedia.org/wikipedia/commons/thumb/d/df/Road_Train_Australia.jpg/800px-Road_Train_Australia.jpg) [http://members.tripod.com/kingsley-foreman/sitebuildercontent/sitebuilderpictures/roadtrainlong.jpg](http://members.tripod.com/kingsley-foreman/sitebuildercontent/sitebuilderpictures/roadtrainlong.jpg) ---
**Author:** ![IAmNotSpartacus](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@IAmNotSpartacus](https://boards.straightdope.com/u/IAmNotSpartacus)\ **Post date:** [April 10, 2008, 4:29am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/5 "2008-04-10T04:29:34Z")
They are quite legal in Nevada and Utah, however not in California. Lots of traffic on these between Salt Lake City and Las Vegas. There is a very large sorting dock built in Lenwood, CA (just outside of Barstow) that was going to be used as a hub for triple trailers coming west, built on the assumption California would allow triples. No such luck, and now there’s a huge concrete warehouse in the middle of the desert that serves no good purpose. ---
**Author:** ![Darryl\_Lict](https://avatars.discourse-cdn.com/v4/letter/d/7cd45c/32.png) [@Darryl\_Lict](https://boards.straightdope.com/u/Darryl_Lict)\ **Post date:** [April 10, 2008, 4:36am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/6 "2008-04-10T04:36:08Z")
[QUOTE=IAmNotSpartacus] They are quite legal in Nevada and Utah, however not in California. Lots of traffic on these between Salt Lake City and Las Vegas. [/QUOTE] I’ve only seen them between Reno and Salt Lake City. There were bunches of them, but they were ALL FedEx. I searched them out in Alice Springs, and saw a couple. There was a photo there of one with something like 6 trailers. ---
**Author:** ![TheLoadedDog](https://avatars.discourse-cdn.com/v4/letter/t/35a633/32.png) [@TheLoadedDog](https://boards.straightdope.com/u/TheLoadedDog)\ **Post date:** [April 10, 2008, 5:43am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/7 "2008-04-10T05:43:29Z")
[Australian road train slideshow](http://youtube.com/watch?v=CVdcBCbwtkw&feature=related) Some normal three or four trailer ones, but also some freakish exhibition ones (country music warning) [Going through the gears](http://youtube.com/watch?v=cuV4b6Y_oEA) in a _smaller_ road train - tunr your speakers up if you like trucks. ---
**Author:** ![zagloba](https://avatars.discourse-cdn.com/v4/letter/z/977dab/32.png) [@zagloba](https://boards.straightdope.com/u/zagloba)\ **Post date:** [April 10, 2008, 6:32am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/8 "2008-04-10T06:32:33Z")
[QUOTE=TheLoadedDog] [Australian road train slideshow](http://youtube.com/watch?v=CVdcBCbwtkw&feature=related) Some normal three or four trailer ones, but also some freakish exhibition ones (country music warning) [Going through the gears](http://youtube.com/watch?v=cuV4b6Y_oEA) in a _smaller_ road train - tunr your speakers up if you like trucks. [/QUOTE] I feel for those road train drivers trying to stay awake across the Nullarbor Plain ---
**Author:** ![TheLoadedDog](https://avatars.discourse-cdn.com/v4/letter/t/35a633/32.png) [@TheLoadedDog](https://boards.straightdope.com/u/TheLoadedDog)\ **Post date:** [April 10, 2008, 6:35am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/9 "2008-04-10T06:35:49Z")
[How to freak out some American tourists](http://youtube.com/watch?v=YS6Qoyn7uME)😃 ---
**Author:** ![Horatio\_Hellpop](https://avatars.discourse-cdn.com/v4/letter/h/e5b9ba/32.png) [@Horatio\_Hellpop](https://boards.straightdope.com/u/Horatio_Hellpop)\ **Post date:** [April 10, 2008, 6:40am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/10 "2008-04-10T06:40:20Z")
When I drove from Maryland to Seattle back in '91, the sight of triple loaders surprised me. ---
**Author:** ![Richard\_Pearse](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/richard_pearse/32/13144_2.png) [@Richard\_Pearse](https://boards.straightdope.com/u/Richard_Pearse)\ **Post date:** [April 10, 2008, 4:38pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/11 "2008-04-10T16:38:25Z")
I was passed by a road train once on my bicycle. Unfortunately it was a single lane road with the lane defined by a traffic island on one side and a curb on the other. There was no shoulder area and by the time the third trailer was passing me I ran out of room, collided with the curb and got thrown over the handlebars onto the footpath. I was very lucky not to have fallen under the wheels. Live and learn as they say. ---
**Author:** ![Omegaman](https://avatars.discourse-cdn.com/v4/letter/o/e480ec/32.png) [@Omegaman](https://boards.straightdope.com/u/Omegaman)\ **Post date:** [April 10, 2008, 6:10pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/12 "2008-04-10T18:10:09Z")
I see them fairly often on I-15 going through town. They kick up a lot of turbulence when they pass. ---
**Author:** ![user\_hostile](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/user_hostile/32/474_2.png) [@user\_hostile](https://boards.straightdope.com/u/user_hostile)\ **Post date:** [April 10, 2008, 6:42pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/13 "2008-04-10T18:42:15Z")
I saw a triple trailer on the Grape-Vine portion of I-5 in California in 1973. Perhaps it was an experiment to see how they would impact the transportation system. I guess it was not so good. ---
**Author:** ![Jake](https://avatars.discourse-cdn.com/v4/letter/j/f475e1/32.png) [@Jake](https://boards.straightdope.com/u/Jake)\ **Post date:** [April 10, 2008, 8:16pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/14 "2008-04-10T20:16:28Z")
[QUOTE=mwbrooks] Especially when you’re on a two lane road with steep shoulders, out on the bare face of the Earth in Nevada somewhere, and you see what you think is one oncoming truck trying to pass another in your lane, then realize it’s actually just a single truck whose third trailer being pushed over into your lane by a stiff crosswind. [/QUOTE] :eek: :eek: That totally scares the crap outta me!! ---
**Author:** ![mwbrooks](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@mwbrooks](https://boards.straightdope.com/u/mwbrooks)\ **Post date:** [April 12, 2008, 3:56am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/15 "2008-04-12T03:56:37Z")
[QUOTE=Jake] :eek: :eek: That totally scares the crap outta me!! [/QUOTE] It caused me no small amount of concern, but I was a bit distracted trying to work out the cycle of the trailer’s weaving and regulate my speed so we passed at the right time. (Totally useless, but it gave me something to do while waiting to see what would really happen.) The one I encountered was on the road up to Tonopah. The road might be bigger now, that was a while ago. ---
**Author:** ![TBG](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@TBG](https://boards.straightdope.com/u/TBG)\ **Post date:** [April 12, 2008, 4:02am UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/16 "2008-04-12T04:02:47Z")
I seem to recall them being illegal in Michigan, due to the lack of control drivers have over the third section. No cite, just memories from drivers training back in the early 90’s. ---
**Author:** ![albino\_manatee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/albino_manatee/32/2_2.png) [@albino\_manatee](https://boards.straightdope.com/u/albino_manatee)\ **Post date:** [February 13, 2016, 3:14pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/17 "2016-02-13T15:14:02Z")
thanks for sharing the stories … reminds me of yesteryear … surprised when i saw my first triple-loader … moved to the outback and saw 'em even longer. whew! _(i found this archived topic while foraging in google … “triple-trailers”)._ ---
**Author:** ![Snnipe\_70E](https://avatars.discourse-cdn.com/v4/letter/s/b5a626/32.png) [@Snnipe\_70E](https://boards.straightdope.com/u/Snnipe_70E)\ **Post date:** [February 13, 2016, 6:37pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/18 "2016-02-13T18:37:07Z")
I think they are dangerous. I do not remember which state I was driving in when one almost wiped out my family. I was driving an 67 VW bus camper. The triple was passing me. I don’t know if the drive nodded off or what. But the tractor swerved and then pulled pack straight. The whip saw effect was wild. And I had no where to go. stomping on the brakes would not have helped because of the distance between where I was at and the length of the trailers. And while the truck was slowing It would have taken too much time for me to try and get in front of it. I now do not trust triple wides. ---
**Author:** ![Tim\_T-Bonham.net](https://avatars.discourse-cdn.com/v4/letter/t/46a35a/32.png) [@Tim\_T-Bonham.net](https://boards.straightdope.com/u/Tim_T-Bonham.net)\ **Post date:** [February 13, 2016, 10:20pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/19 "2016-02-13T22:20:53Z")
Back in the 1990’s, working for a wholesale grocer, I recall that triple trailers were legal in Iowa, but only doubles were allowed in Minnesota. So there was a location just on the Iowa side of the Minnesota-Iowa boder where truckers would drop the 3rd trailer, and another driver & tractor would be sent to pick iit up and bring it the rest of the way. If the dispatchers could schedule them right, there would be 2 triples each dropping the 3rd trailer at about the same time, so the extra driver could pick up both, and pull a double rather than a small single the rest of the way. ---
**Author:** ![boytyperanma](https://avatars.discourse-cdn.com/v4/letter/b/4491bb/32.png) [@boytyperanma](https://boards.straightdope.com/u/boytyperanma)\ **Post date:** [February 13, 2016, 10:33pm UTC](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653/20 "2016-02-13T22:33:26Z")
In MA you can run double ‘pups’(28ft trailers) anywhere in the state. You can run double 48’s only on the Mass Pike. Triples aren’t allowed anywhere in the state. [Next page](https://boards.straightdope.com/t/trucks-hauling-three-trailers-is-this-a-new-thing-or-am-i-really-unobservant/444653.md?page=2)