Converting A Trailer

The concept of re-purposing or converting a trailer is absolutely awesome.  My hat’s off to anyone who can find a way to reuse and convert something from end-of-life to new-again.  We need more of that in our world!

To that end, I want to share a thought from a recent email question about re-purposing a trailer.  Here’s the context of the note (edits for flow and only sharing the critical parts).

The Note & Question

“I am looking at converting a trailer as inexpensively as possible.  Looking to make a general utility trailer mostly to haul yard waste and landscaping supplies, but I also want to haul a car if necessary.  I was wondering from a strength, weight hauling capacity and general towability, would a 20-25 foot boat trailer or 20 foot travel trailer frame be better to start in the long run?”

Answers:  Converting A Trailer

Let me ask you first:  How would you reply to this question?  (Please put your answers in the comments.)

Truly, it makes us excited to see someone thinking outside the store-front, so I want to boost it.  However, in this situation, practicality might not sound so encouraging.  While not exactly reinforcing, this is the answer I gave.  (Well, the nuts and bolts of it.)  I illustrate with this, because I want everyone to have success with their projects, because frustration (or worse, disaster) is not helpful.

“Here’s a thought.  If you know you’re going to need a good utility trailer, then build a utility trailer.  Then, on the rare occasion you might need to haul a car, rent a car hauler.  To re-purpose for a utility trailer, I’d definitely start with a travel trailer frame.”

Looking at the big picture often changes the perspective.  It sounds great to have one trailer to do it all, but sometimes that’s not the big picture solution.  Of course, I can’t pretend to know the situation, but from the note, it sounds like hauling a car is more of a question mark.

The Reasoning Is In Practicality

Something to carry a car is large and strong, probably way overkill for most utility trailer needs.  Then, car haulers are big when it comes to maneuverability and storage.  Finally, and perhaps most important, it is a total rebuild of an RV or boat trailer to make something to haul a car.  Might even be cheaper to start from scratch.

Here’s the thing.  When carrying a car, all the weight is focused on four locations.  The tires.  That means just 4 significant loading points on the trailer bed.  On the other hand, with most utility trailer loads, the weight is spread out over a lot of area.  Think of hauling gravel or yard waste or tree branches.  They touch the trailer bed in lots of places so the load is not focused in one spot.  Car haulers are very strong at the perimeter so the car can drive on without doing damage.  The jobs of these two kinds of trailers really are very different, and that means the engineering is different.

If you want a car hauler because you move cars all the time and occasionally use it as a utility trailer, the story is different.  I think that’s a wonderful combination, but I’d still advise against starting with an RV or boat trailer frame.  Neither of those trailer types are made, as a base, for the perimeter and point loading of carrying a car.


While I’m sorry the answer is not super supportive, it’s honest.  I’m not trying to dissuade the trailer conversion.  Since it is a utility trailer first, and a car hauler (maybe), I’d just make an awesome utility trailer for doing what you know you’ll be doing, and start with the RV trailer frame.  Rent a car hauler if the rare occasion comes up that you need one.

Help With Converting A Trailer

As mentioned, we support the conversion ideas.  In fact, we have already published several articles for guidance and perspective.  Here are a few.

  1. How To Make A Trailer Longer talks about converting a shorter trailer into a longer one.
  2. Then the article with Tips to Strengthen A Trailer Frame looks at ways to stiffen a frame, or to add strength to carry more.
  3. Where Does The Axle Go? is a great article for those building new trailer and needing to calculate for the axle position.  Then, for those converting a trailer or trying to fix stability issues with an existing trailer, we have the article Calculating Axle Position.
  4. Axles 101 is a great place to learn and make sure the available axles will really do what you’re looking for.  I recommend reading with an eye to understanding.
  5. Finally, we have a couple articles looking at some common mistakes with converting a trailer.  What’s Wrong With This Picture?, and then Would You Buy This?

Working with an older trailer or even just older trailer parts can require patience.  If this is your endeavor, we certainly salute you as well as wish you the best of luck.  It’s rewarding, for sure, but also a bunch of work.

Like the old adage:  Run what you brung.  Our respect and congratulations to those who re-purpose a trailer.

Good Luck With Your Project !!


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