Car Hauler Trailers — New Trailer Plans

Where do you get plans for true, tough, Car Hauler trailers.  After a ton of market and product study, we are stepping in and stepping up.  Our niche is engineering better plans for DIY, so read on to learn about our approach to Equipment Transport and Car Hauler Trailers.  This is how we think in design.

The tradition of Mechanical Elements has now expanded into another trailer plans category — for hauling cars, and transporting equipment.  New Car Hauler Plans are in the Specialty Trailers Section of the Plans Store.

Thinking Car Hauler Trailers

Car Hauler Design ResearchFor a long time we have looked at various car hauler trailers to see what’s around.  There are good ideas everywhere, then there are head slappers too.  For many reasons, recently I’ve been keen on Car Hauler / Equipment Transport trailers.  So, I’ve modeled some existing trailers and found many won’t do what they say – well, at least not to the level of safety I am willing to pull with a full load.

Can I do better?  Oh yeah.  No question, but you can decide.  Read below to understand our master plan for car hauler trailers / equipment transports.

So, there’s the motivation.  Now, the execution.

Trailer Specifications:

When starting a new project, we like to know where we’re going.  So, we create a thought map, or specification.  What is on your list for a dream Car Hauler Trailer?

First, the overall style.  Because of the length, tandem axle suspension seems most appropriate.  Beyond that, there seems to be 2 camps, each with 2 camps for Car Hauler Trailers.

Which Style Do You Want? Deck Style
Solid, Fixed Deck Platform Tilt Deck
Traditional Fenders
(fixed, pivot, or removable)
Drive-Over Fenders
(wide, higher clearance vehicles)

From my point of view, these all have advantages, and purposes, so there is no reason to say one is better.  Well, that means we will eventually need to develop several different trailers.

What are the Implications?

1.  A typical car hauler deck is wide enough for most vehicles to fit between the trailer wheels.  That means most decks don’t need to extend wider than the main frame beams.  However, with low vehicles, fixed fenders can cause door opening issues.  So, that’s why removable fenders are popular.

2. For wide vehicles, driving over the fenders offers simplicity.  You just drive on, and over the fenders, which is great for higher clearance vehicles.  While that is fun to consider, it really means if the vehicle are wide enough to hit both fenders, they probably need more deck.  So, for Drive-Over fenders, the fore and aft deck should be wider than just the area between the main rails.

3. Interestingly, all the above apply to both Fixed Deck trailers and to the Tilt Top Decks.

4. Ramps are frequently part of the Fixed Deck system for loading.  On the other hand, with Tilt Deck trailers ramps are usually not needed.

5. Structure required for Tilt Decks is quite a bit more involved than for a Fixed Deck.  That means a Fixed Deck trailer can weigh less for the same capacity.

Trailer Size

Next are the questions of both size and capacity.  Let’s start with size.

Most car hauler trailers are max width, meaning deck width between the wheels is around 82″.  When you add wheels and tires, the trailer width is 8.5′, which is the max size for most places without a permit.  And, it works for most vehicles.  See above about drive-over fenders.

Length is a different story.  Car hauler trailers range from about 12′ long to about 24’+.  Some equipment transport trailers are longer, but very few vehicles exceed a length that won’t fit a 24′ trailer.  Well, we’ll side-step the multi-car trailers for the moment.

What is the right length?  16′ is the most common, but the 18′ market seems to be growing fastest at the moment.  20′ is also very common.  So, for our trailer plans, we’ll start with 20′ (giving an option for 19′ or 18′), then move from there depending on customer feedback.

Load Capacity

A 7000 lb capacity trailer will carry most cars.  Not so good for trucks or larger SUV’s, and usually inadequate for a lot of equipment.  7000 lbs is quite popular.

The next capacity step is 10,400 lbs.  That makes the trailer a little heavier, but it is sufficient for most cars, trucks and SUV’s.

We can say the same for 12,000 lb capacity car hauler trailers.  While 12,000 lb trailers are not as common, it is a great capacity for many needs, and especially for equipment transport.

Then, we jump to 14,000 lb and 16,000 lb trailers.  Very few passenger vehicles need this capacity, so these big boys are normally for equipment transport.  The trailers are heavier, and sometimes longer.

So, what capacity should we choose?  Let’s start in the middle.  Our first car hauler trailer is a practical 10,400 lb capacity.  We’ll listen to your input for where we go next.  Let us know.


A low profile makes sense for most car hauler trailers.  That means lower profile beams.  Most 10K car haulers have 5″ C-Channel to get a low-ish profile, but that is not quite strong enough for our standards in this capacity.

For this first trailer, we want the same 5″ tall beams for a low deck height, but . . . How do we balance height with strength?  We choose a mixed approach with I-Beam constructionI-Beams offer an excellent strength to height to weight ratio, so the trailer is very robust.

To help understand the need for robustness, here is an animation of the I-Beam frame in 3 conditions.  With an evenly distributed load, then yes, the I-Beam design is a little much.  However, with a long vehicle on it, like the F-150 of our previous post, we see it’s a good thing.

Changes with Loading

A really interesting point is the load position.  Moving the truck forward 18″ changes the stress quite a bit.  Since very few people place a car (or truck or equipment) based on actual tongue weight, to me, that means the trailer must handle a bunch of non-optimum positions.  So, we’ll make it strong and the trailer will do what YOU say, not what some engineer at the factory HOPES you do.

So those are the primary thoughts in starting a new project for Car Hauler Trailers.  Next, there are a ton of possible options, so let’s look at those.

Options For Car Hauler Trailers

Since there are a bunch, I won’t dwell long on any one.

  1. Axles.  Choose axles to share the load.  Options include Straight or Drop, Spring types (eye-eye, or slippers), Overslung or Underslung springs, Brake types, Hub styles, Bolt Patterns, Camber or not.  The required axle Capacity is the load rating of the trailer.
  2. Car Hauler Deck OptionsDecking style and deck materialThese are all options. – Plank Deck (Full or Split);  Sheet (Plywood or Metal).  The images show these options.
  3. Ramps we mention above, but where do they store?  Some store in the center of the deck.  Some store by sliding-in under the deck.  Still others have a rack on the side.  No need to limit it, choose what you want.
  4. Tie-Down Anchor Points are important for Car Hauler Trailers.  In my opinion, we need many, so our plans have tie-points covered.
  5. Dovetail.  Some people like them, some people don’t, so, we give it a nod in the plans.  However, the prime design is a flat deck.
  6. A Front Rail is an option.
  7. Many component choices and options are available.
    1. Hitch styles – you choose, of course, though we show an adjustable channel style.
    2. Jacks – Plans show some common options and give structure to mount them – for the tongue, and for rear loading.
    3.  Toolbox – Choose one or not.
    4. Winch – Your choice.  We think it’s good for car hauler trailers, so we give choices.  Add one permanent, or removable (so it’s not in the weather and not a theft temptation).  Options are in the plans.
  8. An electrical wiring diagram – with options – included.

Car Trailer & Equipment Transport Plans

All the above are the essence of what our new car hauler / equipment transport trailers are about.  Of course, there is a lot more in the details.  If you like our thinking, then let us know.  If you think we’ve fallen off our rockers, let us know that too.

For now, we have the first of our Car trailers in the plans store.  Box A in the table above.  A 20′ 10K Fixed Deck with the option for removable fenders, then the slightly higher capacity 18.5′ 12K Fixed Deck for higher capacity in a similar design.  Want something even farther up the Heavy Duty scale?  How about a 14,000 lb. version of the 20′ trailer.  Or, build it with the option for 16,000 lbs. capacity.  Or at 24′ Length!

We also have a trailer in box C of the table above.  Similar in size and strength this 18.5′ 12K Car Hauler has Drive-Over fenders for the wide stance Vehicles like built 4×4’s and dualies.  Drive right up and over the fenders.

All of these trailers have many options to choose from and/or to customize.

We’ll add more car hauler trailers with time.  In the meantime, please have a look and let us know what you think.  Tell us what you’re looking for in car hauler trailers – and for equipment transport trailers?  Let us know, and we’ll consider it in our future planning.  Thank you.

What Makes Our Trailer Plans Different?

First, our plans have Full Engineering.  We are not a weld shop with AutoCAD.  Nor a trailer parts store looking to sell more parts.  We are first, an Engineering Company with a ton of experience in product design and development.  Because Engineering is our primary business, project plans from Mechanical Elements are top of the line.

Plans For Car Hauler TrailersSecond, the plans come from an engineer that loves DIY and building in the shop too.  Sure, engineers often have the reputation of a nerd sitting in a cubical wondering what happens to the design once it leaves the desk, but not here.  I build much of what I design, which includes literally hundreds of products from toys to medical tech, from simple tools to precision robotic machines.  Fine precision parts and hard-core components.  — And, the plans include bits of all I’ve learned.  Want to see?  Check out the Big Slide Show.

Third, we offer more.  Our plans are more complete with more options, better instructions, and more information.  Of course, plans include a Bill of Materials, a cut list, components list, etc.  But, it’s not just the plans and documentation.  The end product is stronger, more capable, and offers greater function.  The goal is to give you the best in DIY Trailer Plans.

These are the things that make our trailer plans different, and better.  Good luck with your Car Hauler Trailers!

Have a wonderful day, and Thank You for reading.


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