The Hidden Danger of a Weight Distribution Hitch

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  • Post category:Guide / Trailer

I have some bad news for you.

I know that’s a rotten way to begin an article, but honesty before civility.

Almost all RVs should use a weight-distribution hitch.

(That’s not the bad news).

But … using a weight-distribution hitch may overload your trailer axles (yikes!)

That’s what I’d call a catch-22, and I am honestly amazed that the conundrum doesn’t pop up more often in educational materials.

But many RVers – maybe even you! – are completely unaware of:

  • A) what a weight-distribution hitch (WDH) is or
  • B) the effect a WDH has on your payload and towing capacity.

Oh, and speaking of bad news, your dealer might be completely baffled on how to properly set up a weight-distribution hitch on your travel trailer.

As you can tell, we have a lot to talk about.

Ross Recommends:

Hey Reader, I don’t like nettlesome ads any more than you do! So for your convenience, I’ve summarized the products mentioned in this article. Click on these links to shop pricing and availability. I get a small commission at no extra cost to you. Thanks for supporting this blog. Enjoy the weekend!

Table of Contents

You Should Understand How This Stuff Works!

Photo Credit: Curt Manufacturing

For whatever reason, weight-distribution hitches are one of the most commonly misunderstood machines in the RV world.

Many an RVer who starts searching online for “RV weight distribution hitches” will be sitting in that same chair three hours later, muttering curse words, browsing comments on RV forums that completely contradict each other, and getting angrier by the click.

My aim is to rescue you from that cyber abyss.

I like to believe all the articles I write on this site are useful, but I’d rank this one in the Top 10 most important. You cannot be a safe RVer without understanding the basics of weight distribution and load leveling!

Yes, these hitches work! Many RVers describe the towing difference as night and day. So don’t ignore this important part! Your safety (and the safety of other motorists on the road) might depend on it.

Do I Need a Weight-Distribution Hitch?

Here’s a simple litmus test:

  • Does your tow vehicle’s rear end sag when you hook up your travel trailer?
  • Does your loaded travel trailer weigh 50 percent or more of your tow vehicle GVWR?
  • Does your loaded trailer weigh more than 5,000 lbs?
  • Are you towing with a short-wheelbase truck or CUV?
  • Is it more difficult than usual to steer or stop quickly?
  • Are you experiencing trailer sway while driving?

If you answered YES to any of those questions, then you almost certainly need an RV weight-distribution hitch.

In fact, almost all pickup truck and SUV manufacturers specify that you must use a WDH if you’re flat-towing more than 5,000 lbs. Ford, Nissan, Ram, and Toyota all specify 5,000 lbs. GMC/Silverado specify 7,000 lbs. (Numbers applicable for 2021 half-ton pickup truck models).

Can I just repeat that?

If you’re towing with a half-ton pickup truck or SUV or smaller, there’s a darn good chance you’ll need a weight-distribution hitch.

What the Hell Is a Weight Distribution Hitch Anyway???!!

I get your frustration! They’re kind of difficult to wrap your head around.

A weight-distribution hitch is also known as a load-leveling hitch or equalization hitch.

This is in comparison to a simple weight-carrying hitch, which is your typical trailer ball on a simple ball mount arm.

Now, this is one article where I’m NOT going to shell out 1,000 words on how something works. I’ll give you a short description, but a video is worth a million words.

Here are some useful videos of RV load-leveling hitches:

*Note: It’s an easy-to-understand video, but Alex IS NOT ACCURATE when he says “a weight-distribution hitch doesn’t do anything to the trailer itself.” THAT IS FALSE! Weight-distribution hitches WILL add weight to the trailer axles.

If you’re interested in the physics of why WDH’s add weight to trailer axles, check out this hidden gem of a video:

Still a little confused?

A simple weight-carrying hitch is a free pivot point. And in the same way that one person rises if someone else sits on the opposite end of a teeter-totter, so the tongue weight of the camper on the hitch causes the front end of the tow vehicle to rise into the air.

A weight-distribution hitch acts as an extended lever and fulcrum. It binds the connection, transforming it from a freely rotating pivot to a semi-locked bridge.

Here’s the simplest way I can explain it.

Point both your index fingers at each other. Touch the tip of one to the other. You can still move one index finger around while keeping the tips touching, right?

Now slide one index finger on top of the other one so the first digits overlap. Imagine wrapping some Scotch tape around the joint.

Now, can you still freely move the top index finger without it partially lifting off the bottom finger??

No, you can’t. Your fingers are forced into alignment.

That’s how a weight-distribution hitch works. It locks the coupling into alignment. The trailer and tow vehicle can’t form a “V” anymore because the spring bars or chains won’t allow pivoting.

What Happens to Axle Weights With a Weight-Distribution Hitch?

(If you want to calculate your own axle weights, you’ll have to set up your own free-body diagram and solve the equilibrium equations).

First, let’s consider what happens if you don’t use a WDH.

OPTION 1: Weight-Carrying Hitch

Remember my teeter-totter analogy? As I said, with a weight-carrying hitch, the front end of the tow vehicle rises up, and the rear axle squats with the added weight.

But it’s actually worse than what you might think.

The front axle actually loses weight! That’s bad for all sorts of reasons.

  • It reduces tow vehicle braking performance and handling.
  • You’ll be more prone to overrsteer when cornering.
  • It increases the risk of trailer sway and fishtailing.
  • It forces your headlights to point up, not out!

Meanwhile, the rear axle gets hit with a double whammy. It not only carries the tongue weight of the trailer, but it also carries the additional weight lost from the front axle! And that’s also bad for all sorts of reasons.

  • It strains the rear axle of the tow vehicle and may overwhelm your payload capacity.
  • It will quickly wear out your tires.

So your headlights are now pointing toward the Big Dipper, your rear tires are severely overloaded, and your front tires lack sufficient traction to effectively brake.

So it’s kinda serious.

In fact, someone could die.

OPTION 2: Weight-Distributing Hitch

Enter: The weight-distribution hitch.

In short, a WDH redistributes the total weight of your tow vehicle and trailer among the three axles.

  • It restores some of the weight to your tow vehicle front axle (good)
  • It decreases some of the excess weight on your tow vehicle rear axle (also good)
  • It increases the weight on your trailer axles (ouch!)

A WDH does not decrease tongue weight. It does not magically push up on the hitch connection. Your total weight across all axles remains the same; the weight just gets more evenly spread out.

Is there a reliable back-of-the-envelope calculation to figure how much weight gets transferred?

Hmmm .. not exactly. A common rule of thumb is that WDH redistributes 1/3 of the tongue weight onto the trailer axles, 1/3 of the TW onto the tow vehicle’s rear axle, and 1/3 of the TW onto the tow vehicle’s front axle.

In reality, redistribution of 20-25 percent is more common than 33 percent.

Exact numbers vary – oh, based on a hundred factors: the height of your ball hitch, the wheelbase of your tow vehicle, the tongue weight of your camper, etc.

Thankfully, you don’t need to run those calculations to configure your hitch.

Every manufacturer of a WDH – Fastway, Andersen, Blue Ox, Weigh-Safe, etc. – provides detailed instructions on how to install and calibrate their hitches.

  • Psst . . . if you’re reading this content anywhere besides Ask The RV Engineer, it’s been illegally “scraped,” and you’re probably on a spam website. So please be careful! Don’t share any private information, and come back to us at www.askthervengineer.com!

3 Types of RV Weight Distribution Hitches

EAZ Lift

Andersen No-Sway

Blue Ox Sway Pro

There are three basic types of weight-distributing hitches:

  1. Round bar
  2. Trunnion/square bar
  3. Chain

Round bar and trunnion-style WDHs are both “spring arm” hitches. Once installed, these metal bars pry upwards on the trailer tongue.

Chain-style WDHs pull; they don’t push. This type of hitch cannot be used with hydraulic surge brakes (found on smaller rental trailers), but they work like magic for most other vehicles!

How do you choose an RV weight-distribution hitch system?

Well, technically speaking, they all do the job. If your only goal is to better distribute the load, then any halfway-decent hitch will do.

But you probably care about ease of use, too. Here are some questions to ask yourself:

  • What weight rating is available? You don’t want a system rated too much (stiff, bouncy ride) or too little (inadequate distribution, damaged components).
  • Will you be installing the WDH yourself? If so, search YouTube for installation videos!
  • How easy to adjust? If you tow with multiple vehicles, you don’t want to be spending 30 minutes each time you adjust your WDH!
  • What is your budget? WDH’s go for $200 to $2,000 and up! I think you should budget $400 to $800 for a good setup + cost of installation.
  • Is sway control built in? And if the system does include sway control, must you manually adjust it for different camper weights, or is the system self-adjusting? P.S. There’s nothing wrong with vertical chain lifts rather than metal brackets, but remember chain lifts don’t offer any sway control!
  • How easy to back up? WDH with friction sway control bars require you to get out, unhook the sway bars, and only then reverse the camper. 2-point, 4-point, and chain-style systems don’t require disassembly to back up.
  • Do you care about noise? If you can’t stand squeaks, then be aware that most round-bar systems have metal-on-metal contact.
  • What drop size do I need? You’ll probably need to select a ball mount with a 2, 4, 6, or 8-inch drop to keep your travel trailer level while being towed.
  • Do I need extra ground clearance? Round spring bar hitches typically have the lowest upfront cost but also the lowest ground clearance.
  • Can I afford the tongue/hitch weight? Lightweight systems like the Andersen weigh just 60-70 lbs; heavier systems like the Weigh-Safe True Tow weigh almost 150 lbs! Remember: You have to subtract this weight from the maximum hitch capacity of your tow vehicle.

How Do You Choose a Brand for the Best RV Weight Distribution Hitch?

There are quite a few options on the market. Trusted manufacturer names include:

  • Fastway
  • Blue Ox
  • Andersen
  • Reese/Pro Series
  • Curt
  • Weigh-Safe
  • EAZ Lift
  • Husky
  • ProRide
  • Hensley

Avoid no-name or knockoff brands (looking at you, Harbor Freight). This is a mission-critical component; you cannot afford failure!

I’m not going to walk through how to select a weight-distribution hitch. That’s a whole article in itself. And if you’re new to RVing, honestly, you won’t know until you try a few models (or talk to your RVing friends).

Personally, I prefer the Andersen Weight Distribution Hitch: lightweight, easy to back up, adaptive sway control, easy to adjust with a wrench, useable across many sizes of trailers, no lubrication grease needed. What’s not to love?

If you want to do your own research, I recommend starting with this 5-point guide from Etrailer.

Overloaded Axles: The Hidden Danger of a Weight-Distribution Hitch

As we have now learned, using a WDH is basically a requirement for most RVs, but they also increase the weight on your trailer axles!

And as you also learned from my expose on GVWR and cargo-carrying capacity, most RVs are already habitually overloaded.

It’s a recipe for tire blowouts.

Let’s consider an example.

Mark owns a 6,400-lb travel trailer (when empty) with a 7,700 GVWR. He’s going on a 5-day camping trip during deer hunting season.

A small armory of munitions, rations, and gear later, his camper now weighs 7,690 lbs. The tongue weight is 10 percent – 770 lbs.

Mark’s pickup truck has a Class 4 Hitch with a maximum weight rating of 1,000 lbs weight-carrying/1,200 lbs weight-distribution.

Mark has checked his numbers. His tongue weight is within the 10-15 percent range. He hasn’t overloaded his camper beyond the GVWR. Good job, Mark!

Like a responsible RVer, Marks weighs his camper at the local CAT scale a few days before he leaves, but he doesn’t use a WDH to tow his rig to the scale.

Two days later, when Mark departs, he uses his weight-distribution hitch (again being a responsible RVer).

Except Mark made a critical mistake.

He didn’t check the Gross Axle Weight (GAW) for his travel trailer.

His dual-axle camper has two 3,500 lbs sprung axles for a total GAWR of 7,000 lbs.

At 7,690 lbs full weight with a 10 percent tongue weight, Mark has 6,920 lbs on his axles. So far, so good. He’s just underneath maximum capacity.

Now, with the weight-distribution hitch installed, Mark has added another 250 lbs to his trailer axles for a total weight of 7,170 lbs.

He’s over his GAWR by 170 bs!

That may not sound like much. But now, his tires are underinflated based on their load index. And even if he airs up his tires, he might need to run 5 mph slower to reduce heat build-up.

But Mark doesn’t know any of this.

Nor does he think about the extra 120 lbs of meat he’s bringing back after a successful hunting trip, which he stores in the pass-thru compartment of his camper.

So now his axles are overloaded by 290 lbs!

Add in the likelihood that one side of his camper probably weighs more than the other …

And it’s easy to see how even a responsible RVer like Mark could easily overload one of his tires by several hundred pounds!

*Pop* *BOOM!*

This is yet another reason to carefully consider the cargo-carrying capacity of an RV before you purchase! At a minimum, aim for 500 lbs per person or 2,000 lbs, whichever is more.

Parting Thoughts

I admit it … the title of this article is kinda clickbait.

You should use a weight-distribution hitch.

The danger isn’t in the hitch itself. It’s the extra weight added to the trailer axles. And since most RV trailers are habitually overloaded, you might be adding on the last straw.

(There goes the camel’s back!)

Parting Thoughts

There’s a lot of information in this article! Here are my top takeaways in no particular order:

  • You probably need a WDH if your camper weighs 5,000 lbs or more when loaded.
  • Check your tow vehicle’s tire pressure before towing! Compare that inflation pressure to their load capacity based on load index tables.
  • Pick a weight-distribution hitch with a weight capacity just above (not below) the maximum loaded weight of your trailer.
  • When weighing your camper and tow vehicle on a certified scale, weigh your rig with the hitch you will be using! Check GAWs for both tow vehicle and trailer.
  • Don’t trust airbags to fix your weight distribution problems.
    You might have to reduce the GVWR of your trailer if you’re using a WDH.
  • My favorite weight-distribution hitch is the Andersen WDH. Your mileage may vary.

Ross Recommends:

Hey Reader, I don’t like nettlesome ads any more than you do! So for your convenience, I’ve summarized the products mentioned in this article. Click on these links to shop pricing and availability. I get a small commission at no extra cost to you. Thanks for supporting this blog. Enjoy the weekend!