How a Weight Distribution Hitch Works

1. 1Tongue weight presses down on the ball, which sits behind the rear axle. The rear axle acts as a pivot and the front of the vehicle lifts.
2. 2The hitch head holds the spring bars at an angle, tilted so that the bars want to spring upward at their far ends.
3. 3The bars are tensioned down to brackets on the trailer's A-frame, typically a couple of feet behind the coupler.
4. 4That tension creates a moment at the hitch head - a twisting force - because the bars are trying to straighten.
5. 5The moment pushes down on the tow vehicle's hitch and simultaneously pushes up on the trailer's nose.
6. 6Load redistributes. Some returns to the tow vehicle's front axle, some transfers back to the trailer's own axles. The rear axle carries less than it did.

Head angle sets the pre-load in the bars. Tilt the head back further and the bars have to bend more to reach the brackets, which means more tension, which means more transfer. That is why most setup instructions begin with washers or a tilt adjustment rather than with the brackets themselves.

Too little tilt and the truck still squats. Too much and the ride turns harsh, the bars run close to their limit, and the trailer's nose is pushed up enough to reduce effective tongue weight - which can introduce sway while curing sag.

A spring bar is a leaf spring. It transfers load by flexing, and a spring only flexes meaningfully within the range it was designed for. A 1,500 lb bar carrying a 600 lb tongue is nearly rigid - it transfers very little and rides harshly. A 600 lb bar carrying 900 lb is overworked, flexing more than intended.

This is why manufacturers publish ranges rather than maximums, and why systems sold in discrete tongue weight bands - Blue Ox's SwayPro runs 350, 550, 750, 1,000, 1,500 and 2,000 lb - make the sizing decision explicit. Aim for the middle of your band.

Quick picks

Tap any row to jump to the full write-up. How these are chosen - and what we do and do not claim to know - is published in full on our research methodology page.

#	Product	Best for	Our read	Price
1	CURT Round Bar Weight Distribution Hitch with Sway Control (14K) Classic round-bar example	Mid-size travel trailers	14,000 lb gross, 1,400 lb tongue	Check price on Amazon→ #ad Affiliate link - we publish no price; Amazon shows the current one
2	CURT TruTrack 4P Weight Distribution Hitch (10-15K) Four-point example	Heavy travel trailers near 15,000 lb	Adjustable friction, 1,000-1,500 lb tongue	Check price on Amazon→ #ad Affiliate link - we publish no price; Amazon shows the current one
3	Andersen No-Sway Weight Distribution Hitch Chain-tensioned example	Anyone who struggles with bar weight	Same principle without steel spring bars	Check price on Amazon→ #ad Affiliate link - we publish no price; Amazon shows the current one

1. Classic round-bar example

CURT Round Bar Weight Distribution Hitch with Sway Control (14K)

CURT · Best for mid-size travel trailers

A conventional round-bar system with integrated lubrication and sway control, rated to 14,000 lb gross and 1,400 lb tongue. The built-in lubrication matters more than it sounds: a dry weight distribution head is the usual source of the groaning people mistake for a failing hitch.

Published specifications

Gross trailer weight

14,000 lb source

Tongue weight

1,400 lb source

Shipping weight

102 lb source

What works

• +Integrated lubrication at the head, which is where the noise usually comes from
• +Round bars sit lower and clear more trailer tongues than trunnion bars
• +Limited lifetime warranty

What does not

• −Round bars hang lower than trunnion bars and are the first thing to catch on a steep driveway
• −Sway control here is a function of the head, not an adjustable four-point system

Skip it if

Skip it if you regularly cross steep transitions - a round bar is the lowest part of the whole rig and will find the pavement before anything else does.

Check price on Amazon→

#ad Affiliate link - we publish no price; Amazon shows the current one

Raw specifications: CURT’s own page. We earn nothing on that link.

2. Four-point example

CURT TruTrack 4P Weight Distribution Hitch (10-15K)

CURT · Best for heavy travel trailers near 15,000 lb

Four-point sway control with adjustable friction, rated to a 15,000 lb trailer and 1,500 lb tongue. The adjustability is the point: you can dial resistance up for a long, tall trailer and back it off for a short one, instead of living with whatever the geometry gives you.

Published specifications

Gross trailer weight

10,000-15,000 lb source

Tongue weight

1,000-1,500 lb source

Rise

5.75 in source

Product weight

123.6 lb source

What works

• +Friction is adjustable rather than fixed by the geometry
• +Rated range covers the tongue weights that half-ton trucks genuinely struggle with
• +Limited lifetime warranty on the structure

What does not

• −At 123.6 lb assembled it is a heavy thing to lift on and off a shank
• −The 10,000 lb floor means it is over-specified for a small trailer

Skip it if

Wrong tool below about 10,000 lb gross trailer weight - under the rated floor the bars barely flex, so you get the weight penalty without the load transfer.

Check price on Amazon→

#ad Affiliate link - we publish no price; Amazon shows the current one

Raw specifications: CURT’s own page. We earn nothing on that link.

3. Chain-tensioned example

Andersen No-Sway Weight Distribution Hitch

Andersen Hitches · Best for anyone who struggles with bar weight

A chain-and-bracket system instead of spring bars, which cuts the assembled weight dramatically and takes the greasy steel bars out of the equation. Sway resistance comes from a friction cone at the ball rather than from bar friction, so it keeps working in reverse.

We have not sourced a full specification table for this model from the manufacturer’s own site at a stable address. Rather than repeat figures we cannot cite, the assessment above is limited to what the design and the maker’s published description genuinely establish.

What works

• +Far lighter to lift and store than a conventional spring-bar system
• +No greased bars to handle, and no bars to drag on a steep transition
• +Tension is set with a wrench rather than a snap-up bracket

What does not

• −Chains and the friction cone need periodic re-tensioning and inspection
• −Behaves differently from a spring-bar hitch, so advice written for those does not transfer cleanly

Skip it if

Not for you if you want a system a trailer shop down the road will recognize instantly - most of the setup advice you will find assumes spring bars.

Check price on Amazon→

#ad Affiliate link - we publish no price; Amazon shows the current one

Raw specifications: Andersen Hitches’s own page. We earn nothing on that link.