How to Adjust a Weight Distribution Hitch (Step-by-Step)

A weight distribution hitch only works if it’s adjusted for your truck and your loaded trailer. Install it out of the box and you might be close, or you might be badly off. And the setup that was right last season may not be right after you add a generator, swap trucks, or load the trailer differently.

This guide is about adjusting: how to measure, how to calculate whether you’re in range, which adjustment fixes which problem, and how to tell from the driver’s seat when something’s off. If you’re installing a hitch for the first time, start with our weight distribution hitch setup guide and come back here to fine-tune.

What “adjusting” a weight distribution hitch actually means

When you drop a trailer tongue on the ball, the rear of the truck squats and the front rises. That takes weight off the front axle, which is the axle that steers and does most of the braking. A weight distribution (WD) hitch uses spring bars as levers to push some of that weight back to the front axle and some onto the trailer axles.

Adjusting the hitch means controlling how much leverage those bars apply. On most hitches you have three adjustment points:

• Ball height: where the hitch head sits on the shank. This sets the starting geometry and trailer levelness.
• Head tilt: how far the head is angled back, set with spacer washers, a tilt bolt, or a cam, depending on the brand. More tilt means more bar tension.
• Bar tension at the trailer frame: the L-bracket hole position (trunnion bars) or the number of chain links (chain-style bars). Raising the bracket or using fewer chain links means more tension.

Check your hitch’s manual for which of these applies. Equal-i-zer, Fastway e2, CURT, Blue Ox, ProPride and Andersen don’t all use the same mechanisms, but the measuring method below works for all of them.

Before you start: tools and conditions

• Level, hard ground. A driveway with even a slight slope will throw off your numbers.
• Load the truck and trailer the way you’ll travel. Fill the water tank (or not) as you normally would, put gear where it rides, and have passengers’ weight accounted for if possible. Tongue weight changes with loading. See what tongue weight is and how to measure it.
• Correct tire pressure on the truck, at the door-sticker value for towing loads.
• A tape measure, a notepad, the wrenches/sockets your hitch needs, and a torque wrench.
• Your truck owner’s manual. Some manufacturers specify a target front-axle restoration percentage or a different measuring method. If your manual says something different from this article, follow the manual.

Step 1: Check ball height first

With the trailer level (front-to-back) on its jack and unhitched, measure from the ground to the top inside of the coupler. Then measure ground to the top of the hitch ball on the unloaded truck. Many hitch makers recommend setting the ball at or slightly above the coupler height, since the truck will squat once loaded. Get this close before you touch tension. If ball height is wrong, everything else will be off too.

Step 2: Measurement A (truck alone)

With the truck uncoupled, measure from the ground straight up to the bottom of the front wheel-well lip, through the center of the wheel. Do both sides and average them if you can. Mark the exact spot with tape so later measurements come from the same place. Write it down as A.

Measuring the rear as well is useful (it shows how much the rear squats), but the calculation uses the front.

Step 3: Measurement B (coupled, bars off)

Couple the trailer and retract the tongue jack fully so the whole tongue weight sits on the ball, with the spring bars not attached. Re-measure the front fender at the same spot. It will be higher than A because the front end lifted. This is B.

Step 4: Measurement C (bars engaged)

Raise the tongue with the jack (lifting the truck’s rear a bit), install the spring bars and lock them onto the brackets or chains, then retract the jack completely. Measure the front fender again. This is C. It should be lower than B, because the bars have pushed weight back to the front axle.

Step 5: Calculate front-axle load restoration

Use the formula published by hitch manufacturers such as Fastway and Equal-i-zer:

Restoration % = 100 × (B − C) ÷ (B − A)

Worked example (illustrative numbers): A = 36″, B = 37″, C = 36¼”. (B − C) = ¾” and (B − A) = 1″, so 100 × 0.75 ÷ 1 = 75%.

Result	What it means	What to do
Below 50%	Under-distributed: too much load on the truck’s rear axle, light front end	Increase tension
50–100%	Within the range most hitch makers publish	Confirm against your owner’s manual, then test drive
Above 100%	Over-distributed: front is lower than unhitched, rear axle unloaded	Reduce tension

Some truck makers publish their own target (for example, restoring the front fender to a specific fraction of its unhitched height). The truck manufacturer’s guidance comes first.

Step 6: Make the adjustment

If you’re under-distributed (need more tension):

• Raise the L-brackets one hole on the trailer frame, or use one fewer chain link.
• Add head tilt (add a spacer washer or rotate the tilt adjustment per your manual).
• Make one change at a time so you know what moved the number.

If you’re over-distributed (need less tension):

• Lower the L-brackets one hole, or add a chain link.
• Remove a spacer washer or reduce head tilt.

The safe sequence for head changes is the one Equal-i-zer lays out in its manual: raise the tongue with the jack, unload and remove the bars, unhitch, make the change, re-hitch, re-engage the bars, retract the jack, and take a new measurement C. Keep the original A and B and recalculate. Repeat until you’re in range.

Safety note: loaded spring bars store a lot of energy. Never try to remove or swing a bar under load. Always take the load off with the tongue jack first, and keep hands and feet clear of the bar’s path.

Step 7: Check trailer pitch

Once restoration is in range, measure the ground to the trailer frame at the front and the rear. Equal-i-zer’s guideline is that if the difference is more than about 1¼”, you should move the hitch head up or down on the shank, then re-check the restoration numbers, because changing ball height changes bar geometry. A trailer that sits nose-high or nose-low can handle poorly and load its axles unevenly.

Step 8: Torque, then test drive

Torque every bolt to the values in your hitch manual. They’re typically high, and the hitch can shift if they’re under-torqued. Then take a short drive with some highway-speed sections and a few firm (safe) stops. Re-check bolt torque after the first trip, as most manuals advise.

How to tell your hitch needs adjusting (on the road)

• Light, floaty steering or a nose-up look: usually under-distributed.
• Porpoising (pitching up and down) over bumps: often too little tension, or the wrong ball height.
• Rear tires feel loose in wet conditions, or the rear end looks raised: possibly over-distributed. Too much weight has come off the rear axle.
• Headlights aimed at the sky at night: the front is light.
• Increased sway: WD helps, but sway has many causes, including tongue weight under roughly 10%, load placement, tires, and speed. See our trailer sway control guide.

When to re-adjust

• You switched tow vehicles or added a truck accessory that changes rear suspension (airbags, helper springs, a heavy bed topper).
• You’re towing a different trailer, or the same trailer loaded very differently.
• Tongue weight changed noticeably (new battery bank, generator on the tongue, full vs. empty fresh tank).
• The hitch was disassembled, or bolts were found loose.
• Handling simply feels different than it used to.

Common adjusting mistakes

• Measuring on a slope or at different spots each time. Tape a reference mark on the fender.
• Adjusting with an empty trailer and then loading up for the trip.
• Cranking tension “until it looks level.” A level-looking truck can be over-distributed. Do the math.
• Using air suspension or airbags to fake it. Airbags can level the rear, but they don’t put weight back on the front axle. Set WD first, and follow your truck manufacturer’s guidance on airbags.
• Exceeding ratings. A WD hitch doesn’t raise your truck’s payload, GVWR, or tow rating. It only spreads the load.

Frequently asked questions

What percentage should a weight distribution hitch restore?

Major hitch makers such as Fastway and Equal-i-zer publish a target of 50–100% front-axle load restoration and say not to exceed 100%. Your truck’s owner’s manual may give a more specific target. If it does, follow it.

Do I raise or lower the L-brackets for more weight distribution?

Raise them, one hole at a time, for more tension. Lower them for less. On chain-style bars, fewer chain links means more tension.

Should the truck sit level when the WD hitch is adjusted?

Not necessarily. The goal is a target front-axle restoration, not a perfectly level truck. Some rear squat is normal. The trailer itself should sit close to level.

Can a weight distribution hitch be too tight?

Yes. Over-distribution (above 100%) takes too much weight off the truck’s rear axle, which can reduce traction and stability, especially on slick roads.

How often should I check my weight distribution adjustment?

Check it whenever the truck, trailer, or load changes significantly, and re-check bolt torque after the first trip following any adjustment. A quick visual check of truck and trailer stance before each trip is good practice.