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Topic: How do Manufacturers spec length?

Posted By: husk on 09/27/10 06:45pm

If I see a manufacturers spec that says the length is 27'10"...does that mean the length of the "box"?...or does it mean total length from rear bumper to end of tongue? If the latter is true, how do I find out the livable space?

Is there an agreed-upon meaning for suffix'es to mfg part numbers...does a 27RBK always mean the same thing for all mfgs?

If there is a standard, where would I find a decoder for what those letters mean?


Posted By: mach8274 on 09/27/10 06:50pm

Typically, When a manufacturer names a floorplan, the numbers in that name are the "box" length. For instance, my TT floorplan is 29FBS. The box is 29 ft, but the overall length from hitch to bumper is 32'6".

Hope this helps.


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Posted By: skipnchar on 09/27/10 06:52pm

Depends on how it's written. If it says "over all length" or listed as "outside dimensions" then it's hitch to bumper. Don't confuse MODEL numbers with length. Sometimes length is included in model numbers but just as often it is not. ON some other occasions model number includes an approximate length of that model trailer.

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Posted By: eric james on 09/27/10 06:58pm

mach8274 wrote:

Typically, When a manufacturer names a floorplan, the numbers in that name are the "box" length. For instance, my TT floorplan is 29FBS. The box is 29 ft, but the overall length from hitch to bumper is 32'6".

Hope this helps.



Usually the number is the living space.

My 290BH is 33' bumper to ball. 29 foot box to live in.

I do call it my 33' suitcase. [emoticon]

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Posted By: bmet2000 on 09/27/10 07:06pm

I have a model 324, but my length is 35' 6". So I imagine my box is 32' 4"

Posted By: husk on 09/27/10 07:08pm

that's kind of what I was afraid of.........different mfg's use different methods. I started thinking a 24BKS was always a 24' ain't, apparently.

Jayco lists "exterior length"....that makes me think it includes the hitch. If not, why not spec "interior length".....that would then be clearly the box length.

What about the letters following the number on the model?

Is there a standard for BKS, etc? thanks again

Posted By: johnrbd on 09/27/10 07:21pm

Third + number/letters designate floor-plan. RL, Rear Living, RK-rear kitchen, BH-bunk house, etc.

Posted By: DutchmenSport on 09/27/10 07:47pm

I think it's a mystery that no one can answer. My Dutchmen Sport said 18 feet. It measured 20 across the floor, and 25 from bumper to hitch. It measured about 22 from the farthest back wall, the the farthest point on the front wall, and the outside measurements of the box never matched anything. I never figured it out. I finally just started using the bumper to hitch length.

My Springdale is almost as confusing!


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Posted By: javaseuf on 09/27/10 08:22pm

Don't go by model number. Visit the manufacturers web-site and look at the specifications for your trailer choice. In my experience, the length in the specs is always the length from bumper to tongue.

Posted By: husk on 09/27/10 08:53pm

yes, it does appear that most, if not all, mfg'ers spec exterior length from bumper to front hitch..

I guess subtracting 3 feet from that measurement would put one about as close as possible to the box size. I assume all mfg'ers are pretty standard about the A frame length leading to the ball hitch(?).

Thanks to all for the responses.

Posted By: Lad79der on 09/27/10 09:03pm

I have a Cherokee 28A+... the box is 30 feet long and the trailer overall is 33' feet long. Not sure why they called it a 28...

So that shows you that using the manufacturers number isnt always the length...

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Posted By: ROBERTSUNRUS on 09/28/10 12:30am

[emoticon] Hi, my trailer's model number is a 25-B. My trailer is considered a 25'er, but is 25' 11"s long total, from bumper to tongue. The "B" means that my trailer has a Queen bed.

"> Bob ">
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Posted By: mobeewan on 09/27/10 11:41pm

I have a Northwood Northwind 27NY it is 28 feet 6 inches from the coupler ball socket to the rear side of the bumper.

Posted By: 2halfs on 09/27/10 11:52pm

Not always true about the whole length being the model model number is 27DS, this means the box is 27 feet. With hitch we are at 30 feet, with bumper....well you know [emoticon] The DS is Dinette Slide. You are correct in thinking there is something in the model number of the trailer. It is just figuring out the manufacture's "code".

As mentioned above, you should go by the specs. And most if not all, will have a website or 800 phone number to call.

When reserving a campsite, and asked the length. I just round to the highest over all length (so we are on the safe side).

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Posted By: W8NONU on 09/28/10 07:14am

Some manufacturers indicate square footage in their model numbers. Good luck with the decoder. [emoticon]

Posted By: DutchmenSport on 09/28/10 06:46pm

Someday, we're going to figure this out, and maybe manufactures will start using some kind of "standard" to measure the length ..... Nah! Probably not. About the time we figure it out, the manufactures will start giving descriptions in metric scale! [emoticon]

Posted By: califron on 09/28/10 06:58pm

Yes make sure of this prior to parking it on the driveway I had 1/2 inch left befor the hitch was nearing the sidewalk..Just made it!

Posted By: tnd2 on 09/28/10 08:04pm

Our Copper Canyon 2991RLS is 33'5" bumper to ball, and 30' body length.

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Posted By: roster2 on 09/28/10 08:19pm

My old Sabre was a 28RBFWS. The box was 28'9". the overall lenght was just over 33'. Now figure this one out, my new Cardnial 5er is a model 3100. You would think 31', nope-it is 36'1" overall.

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Posted By: RUFFSTUFF on 09/29/10 07:18pm

I have a Coleman CT250, the brochure states that the exterior length is 26' 2"... I have no idea how long this thing is!

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