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Does a 6 x 12 enclosed trailer with wheels underneath exist?

Posted:
Sun Dec 31, 2017 12:19 pm
by jasonc424
Hi friends,
I would like to start an enclosed trailer build - 6 or 6.5 feet wide, 7 at the most, and 10 or 12 feet long. I have found 8 foot trailers with the wheels underneath, but anything smaller seems to only have the wheels sticking out under fenders. I prefer to pull a rig that is not 8 foot wide with the wheels, so would prefer that they are under the chassis. Do trailers like this exist? Which companies sell them? Are there companies that would do a custom build to meet these requirements? Thanks!
Jason
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Sun Dec 31, 2017 4:35 pm
by aggie79
Don (MtnDon) built a 6' x 12' CT conversion with inboard wheels. Here is a link to his build journal:
http://www.tnttt.com/viewtopic.php?f=42&t=58336. Unfortunately he used photobucket to host his images so there aren't any build pictures to look at.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Sun Dec 31, 2017 5:05 pm
by jasonc424
Thank you Tom, I sent Don a PM
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Sun Dec 31, 2017 5:21 pm
by John61CT
I want under 7 1/2' wide and wheels-fully-under still requires a DIY job
I've concluded a custom build is required, I'm OK doing the living space, just need the bottom done.
Not really that expensive either once you have the design nailed down, there are good welders all over the place, and most don't make huge money.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Sun Dec 31, 2017 8:31 pm
by Rainier70
The only thing I would be careful of is to keep your weight down low in the trailer. Six wide with the wheels under is getting to be a pretty narrow wheelbase for the height. In talking with a manufacturer they emphasized the problems of a narrow wheelbase on a tall trailer.
It can be done fine, but be aware that the narrower you go, the more "tip" factor in high winds and something like if a wheel sinks in an off road situation. Keeping the weight low in the trailer will help to offset that.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Sun Dec 31, 2017 11:30 pm
by flboy
Rainier70 wrote:The only thing I would be careful of is to keep your weight down low in the trailer. Six wide with the wheels under is getting to be a pretty narrow wheelbase for the height. In talking with a manufacturer they emphasized the problems of a narrow wheelbase on a tall trailer.
It can be done fine, but be aware that the narrower you go, the more "tip" factor in high winds and something like if a wheel sinks in an off road situation. Keeping the weight low in the trailer will help to offset that.
Absolutely correct. The wider stance brings with it a lot more stability and etc. during tow. Probably more pros than cons compared to the narrower wheel base assuming a minimum 6' height.
What are the advantages to the inboard wheels in this case? Is it just the towing width you are concerned with? You get use to judging the width real quick (forgive me if you already tow a lot and this is not the issue). I can tell you, I wish my trailer was only as wide as my truck at times. The thing I hate most are the cement barriers on the highway with no shoulder. In those cases, I hug the white line on the opposite side and don't look at the cement barriers (You tend to drift towards whatever you are looking at) , or I change lanes and move to the center or outer lanes on windy days (the speedsters just have to deal with me going the speed limit until the barriers end).
99.9% of the time, I know if I hug the white line on the other side... no issues.. so I focus on the drivers side. I have a Class B CDL and Drive a very large bus at times when I take kids to camp. It takes up the whole lane and the crosswinds do push it around some... so after white knuckled day of driving that old pusher bus with way too much play in the steering.... the CTC behind the F150 seems like a cake walk.
Just be careful with height and load as Rainier70 said if you go with the inboard wheels. I know there are trailers with narrow stances, but they typically do not have significant wind loading on the sides (open trailer or 4-5ft tall) which also pretty much guarantees that the weight will be down low also.
Best of luck with your choices and I hope you find what you are looking for.

Happy New Years.. btw.. it is about that time here.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 8:09 am
by Hader
The points brought up by Rainier70 (Cindy) & flboy (Don), sound valid and deserve being considered. I wish we have an engineer that can shed some light on this.
When we started looking into buying a cargo trailer for conversion, weight and width (pounds & air resistance) of trailer was the 1st priority .
Our tow vehicle was a 1997 4Runner (220K miles), and it can only handle so much. Height was not considered at all.
The other concern was the Footprint of the trailer and how wide would we be comfortable with going down the road.
We now have another tow vehicle, a 1998 F350 van (less than 40K miles, It can handle all kind of tow). But, for us towing a trailer would be a now-and-then camping trip vs. frequent or regular activity. Infrequency makes it more difficult to be accustomed to handling a wider trailer in town or narrow roads (sometimes, we forget about the width of the wheels). I wish we can comfortably handle a wider trailer.
Some would say it’s experience that matters! I respectfully disagree. I drove 18 wheelers for 12 years, owned RVs & a 8 1/2’ cargo trailer. Frequency makes a difference.
Buying a cargo trailer for a conversion is different from buying an RV! A cargo trailer allows you to buy what suits you as an individual, vs. RV for all.
This subject has an effect on the safety of all, and deserves more discussion and personal input from all.
Happy New Year!
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 9:26 am
by MtnDon
As the owner of a 6 foot wide, 6-1/2 foot tall CTC I feel I should make some input here.
One reason we chose 6 foot wide so the trailer would more or less approximate the width of the truck pulling it. That means No need for extra wide mirrors. It also means somewhat lesser drag pulling it through the air. The narrower width means it can be pulled and backed down narrower forest roads easier or at least more comfortably. Downsides include not being able to place the bed crosswise if you are tall. But crosswise beds have their own detraction's. The inboard wheel wells also rob you of floor space. We had to take that into account when planning the interior. When used as a cargo hauling trailer the inside wheel wells would be an impediment. That is the main reason a cargo trailer is built with the wheel outboard of the box. Plus a simple box without inside wheel wells is easier to build. We did have to pay something extra; don't recall how much.
Our CTC is the standard lower to the ground type; lower to the ground than a typical RV trailer. That also makes it more stable than a trailer that sits higher like most RV trailers do. It is mostly an empty box, so yes the weight is low. Fresh water tank is located on the floor under the bed. Grey water tank is between the frame rails. Fridge, batteries, water heater, etc are all at floor level. The only items elevated are the small A/C and the microwave.
We have towed it throughout the southwest with no drama at any time. It tows dead straight, no wiggles or waggles. Well, maybe a slight twitch when meeting a semi trailer truck on a 2 lane highway with some cross wind. The trailer does not sway violently though. Truck and trailer shift together. I have towed other trailers that made me nervous in winds. This one does not.
We have electric brakes on it. The brakes are a must in my book, even though my state says it does not need them. We also have US made tires. Plus a spare, just in case.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 10:03 am
by onlyridepark
When I ordered my trailer from ATG, I was wanting to do the same thing as you with the wheels underneath. There was some confusion and it didn't happen but they did say they could build it that way. They were the only builder I talked to that was willing to do it.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:21 pm
by John61CT
At 7'4" I don't think stability is an issue, long as my COG is low as practical.
Wheels need to be inside that profile so the whole thing fits in a 20' conex.
I plan a pop-up design, rolling height with panels under 6'6", for highway mpg and handling issues.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:23 pm
by John61CT
MtnDon wrote: Downsides include not being able to place the bed crosswise if you are tall. But crosswise beds have their own detraction's.
for examples please?
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:42 pm
by jasonc424
Rainier70 wrote:The only thing I would be careful of is to keep your weight down low in the trailer. Six wide with the wheels under is getting to be a pretty narrow wheelbase for the height. In talking with a manufacturer they emphasized the problems of a narrow wheelbase on a tall trailer.
It can be done fine, but be aware that the narrower you go, the more "tip" factor in high winds and something like if a wheel sinks in an off road situation. Keeping the weight low in the trailer will help to offset that.
Thank you, I see your point. We currently have a T@b 320 that we pull and the wheels are underneath, so I hadn't really considered that a cargo trailer might be different.
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:48 pm
by jasonc424
The thing I hate most are the cement barriers on the highway with no shoulder.
Happy New Years.. btw.. it is about that time here.[/quote]
Bingo, this is the concern, especially for my wife. She is happy towing our T@b which is about 6 feet wide, but expresses concerns about those barriers and prefers that we don't end up in a rig that totals over 7 feet in width. Right now if we are driving straight and our Tacoma fits, then the trailer fits.
I wonder if there is a compromise, wheels partly under and partly exposed?
Happy New Year
J
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:58 pm
by jasonc424
MtnDon wrote:When used as a cargo hauling trailer the inside wheel wells would be an impediment. That is the main reason a cargo trailer is built with the wheel outboard of the box. Plus a simple box without inside wheel wells is easier to build.
This was our original thought, that it has more to do with the typical use of a cargo hauler and we had not considered that the wider stance would be safer in the wind. To add to your point the trailers that are at or approaching the maximum legal width have tires underneath, I wonder if they have any problem with cross wind.
Could it be that good tires, electric brakes and low center of gravity may be enough to offset the concerns of crosswinds?
Re: Does a 6 x 12 enclosed trailer with wheels underneath ex

Posted:
Mon Jan 01, 2018 12:59 pm
by jasonc424
onlyridepark wrote:When I ordered my trailer from ATG, I was wanting to do the same thing as you with the wheels underneath. There was some confusion and it didn't happen but they did say they could build it that way. They were the only builder I talked to that was willing to do it.
Good to know, thank you!