Weight Distribution Hitch Setup: Your Truck Maker Sets the Target

A weight distribution hitch that tows badly is usually set up badly. It's easy to judge one by how level the truck looks from behind and never check the front end, which is the part the setup exists to fix. Setting one up takes a tape measure, a pencil and a level spot, and checking it takes a trip across a scale.

Two documents run the job. Your hitch maker's manual says how to adjust the hardware, and your truck maker's owner's manual or towing guide says how much front-end load to put back. This guide follows Equal-i-zer's and Andersen's published procedures step by step and lines them up against what Ford, GM, Ram and Toyota print. If you haven't settled whether your truck and trailer need weight distribution at all, start with our guide to that question.

Before you touch a wrench

The lowest rating in the chain decides what you can tow, and the hitch is rarely the lowest. Equal-i-zer's manual says never to exceed the specified weight ratings for the trailer, the tow vehicle, the hitch, the hitch ball or any other towing equipment, and Andersen's says your combined load and trailer weight should stay under the lowest weight rating of your tires, vehicle and hitch. That list includes your truck's tow rating for its exact configuration, its payload and rear axle ratings, its tongue-weight limit with and without weight distribution, the receiver's rating, the hitch, the ball, the trailer's coupler and the tires. We don't print any truck's ratings: they change with cab, bed, engine, axle ratio and package, and they live in your owner's manual, the towing guide for your model year and the label on the driver's door jamb.

Your owner's manual answers two questions before setup starts: whether your truck maker allows a weight distribution hitch on your truck, and what the receiver is rated for with and without one. Setting the hitch moves load between axles and takes none of it off your payload; the scale check below settles that sum.

Then set the stage the way both hitch makers do. Load the truck and trailer as they'll travel, with propane, water, batteries and gear on board, because Equal-i-zer's manual says a setup is only accurate that way and its tongue-weight warning (stay inside 10 to 15% of the loaded trailer) only means something with a loaded trailer. Park on flat, level ground with the truck and trailer in line, chock the trailer, and set every tire to its proper pressure. Turn off any auto-leveling or air suspension the way your owner's manual describes; Equal-i-zer says those systems reduce the weight distribution you get once setup is done. Then level the trailer by measuring from the ground to its frame at the front and the back until the two match.

The three measurements that run the setup

Every maker in this guide uses the same yardstick: the height of the truck's front wheel opening, unhitched and hitched. Equal-i-zer measures from the ground to the wheel well through the center of the axle, Ford to the top of the front fender lip above the center of the wheel, GM and Ram to the top of the front wheel opening on the fender. That's the same spot, and the same spot every time is what matters. Equal-i-zer suggests measuring both sides and averaging them. Here's the worksheet, with an example we made up to show the math:

That last line is Equal-i-zer's formula, and it's the same idea as Ford's correction factor and GM's halfway point: the share of the front-end rise the hitch takes back out. At 0% the front sits as high as it does with no weight distribution at all. At 100% it's back to its unhitched height. In Equal-i-zer's own example, 30 in unhitched, 31 in hitched and 30-1/4 in with the arms on works out to 75%.

How much to take back: your truck maker sets it

Here's what each maker's document prints, and what it would mean for the hypothetical truck above (35 in unhitched, 36-1/2 in hitched):

The documents: Ford's 2026 RV and trailer towing guide and 2020 F-150 owner's manual, GM's 2025 Silverado 1500 and Colorado manuals (the Sierra 1500 and Canyon manuals print the same targets), Ram's 2025 Ram 1500 manual and Toyota's 2025 Tundra manual. Each is one model year; check the same page in yours.

Read the example's measured 35-7/8 in against that table and the same reading lands on both sides of the line. It's short of the half that Ford's 2026 guide and GM's 1500 manuals ask for, well short of Toyota's all-the-way-back, and past the quarter mark in Ford's 2020 F-150 manual. Ram prints a target only for trucks with air suspension, so on a DT without it, ask Ram. Ford's 2026 guides give the Ranger and Maverick a weight-carrying receiver rating only and print "Not Required" in the correction-factor column for both, so ask Ford before you fit either hitch to one.

The hitch makers defer to these numbers. Equal-i-zer's manual calls 50 to 100% good adjustment, says never to exceed 100%, and defines too little and too much against the minimum and maximum in your tow vehicle owner's manual where it gives one. Andersen's manual says to follow the truck and trailer makers' weight distribution guidelines, then sight the truck pretty close to level. Where your truck maker's number falls outside the hitch maker's range, as the 2020 F-150's quarter does against Equal-i-zer's 50% floor, we'd follow the truck maker and ask both companies to confirm. Overshooting is a problem too: Equal-i-zer warns that past 100% the hitch takes too much weight off the rear axle, which costs traction and can lead to a jackknife on slick roads, and Ford's 2020 manual says never to set the bars so the rear bumper ends up higher than it was before you hooked up.

Setting up the Equal-i-zer, step by step

Equal-i-zer's owner's manual is the procedure, and it prints the torque value for every bolt. Use its numbers, not ours or a forum's; you'll need a torque wrench big enough for the shank bolts and the hitch ball. Equal-i-zer's steps, in its order, summarized:

1. Ball and head: use a ball with a 1-1/4 in threaded shank no longer than 2-3/8 in, rated at or above the trailer's gross weight. Put the spacer rivet with its washers in the back of the head, slide the head onto the shank with the top of the ball 0 to 1 in above the top of the level trailer's coupler, hand-tighten, and snug the angle set bolt against the shank.
2. Brackets: hang them 27 to 32 in back from the center of the coupler, measured along the frame, the same distance on both sides. Pinch the link plates flat against the frame with no gap above or below it before you tighten anything, and don't use an impact wrench on these bolts.
3. Arms on: with the trailer coupled, raise the tongue jack until the spring arms swing onto the L-brackets, pin them, and retract the jack fully. Check for at least 3 in between the end of each arm and the center of its bracket; if there's less, move the brackets forward.
4. Measure C and work out the percentage: 100 x (B - C) / (B - A). Under your target, add spacer washers or raise the L-brackets. Over it, remove washers or lower the L-brackets.
5. Adjust with the arms off: jack the rig up, take the arms off, unhitch, change the washers or the bracket holes, hitch up again and re-measure C against your original A and B. Repeat until it lands.
6. Level the trailer: if the front and rear of the trailer frame differ by more than 1-1/4 in, move the head up or down on the shank and re-measure C. Under 1-1/4 in, finish up and tow a short distance before changing anything.
7. Tighten and recheck: torque every bolt to the manual's values once the numbers are right. Equal-i-zer's support page says to recheck the weight distribution after the first 50 to 100 miles, loaded, and whenever the load changes much, and to check the angle set bolt after the first 150 miles.

Two Equal-i-zer documents disagree on the starting point. The printed manual says to start with six spacer washers for most setups and allows brackets anywhere from 27 to 32 in; Equal-i-zer's online installation guide starts most setups at five washers (six when the loaded tongue is over 90% of the hitch's tongue rating, four for some light tongues) and puts the brackets at 32 in wherever the frame allows, 27 in at the closest. Either one is a first guess; the three measurements decide. The online guide also says that moving the ball up slightly reduces the weight distribution a setup gives and moving it down adds some, so a pitch correction means measuring C again. Owners who get an Equal-i-zer right describe the washers, the ball height and the bracket holes as one adjustment you tune together, then confirm on a scale.

Setting up the Andersen, step by step

Andersen's installation manual works differently: chains and a friction cone in place of spring bars, and a tension nut on each chain in place of washers and bracket holes. It also gives torque values and the number of turns to start from. Follow those, not this page. Andersen's procedure, summarized:

1. Ball height: level the trailer, slide the rack into the receiver, and bolt the ball housing so the top of the ball sits 1 to 2 in above the top of the coupler, and 2 in for half-ton trucks with heavier trailers. Don't grease the ball or the coupler.
2. Couple light: latch the coupler with almost no weight on the ball, pin the sway plate under the ball, and get the plate close to square with the trailer. It doesn't have to be perfect, and Andersen says not to use a metal hammer on it.
3. Chains and brackets: attach each chain to its outside bracket with the red spring, nylon washer and metal washer in that order; Andersen says the nut will split the spring without the washers. Pull the chains tight, clamp the brackets to the frame at an angle, then seat the set screws. Andersen's FAQ says to measure from the center of the coupler to the center of each bracket and make the two equal.
4. Tension: hand-tighten both tension nuts, then turn them the amount the manual specifies, until the red springs bulge slightly.
5. Check level: lower the trailer onto the ball. Andersen wants the trailer level, within about an inch front to back per its FAQ, and the truck pretty close to level, and says chasing a perfectly level truck isn't necessary.
6. Adjust in small steps: change both tension nuts in small steps, as the manual describes, and check the level again after each change.

One note on ball height. Equal-i-zer sets the top of the ball 0 to 1 in above the coupler and Andersen 1 to 2 in, but Ford's 2026 RV and trailer towing guide says to set the ball mount height per the manufacturer's instructions so the ball is the same height as the trailer's coupler before hookup. The hitch maker's manual governs how you set up its hitch; on a Ford, if the two don't line up on your rig, ask Ford and the hitch maker which height to use. Either way, Ford's guide wants the trailer level to slightly nose down once the bars are set.

We'd add one step Andersen's manual leaves to the truck maker: measure the front wheel well, A, B and C, exactly as in the worksheet above, and compare the result with your truck maker's target. Andersen's manual tells you to follow those guidelines, and sighting a truck level won't show whether the front end got half its rise back. Andersen's FAQ says that in its 900 lb tongue example the hitch moves roughly 30% of the tongue weight forward. That's a different measure from a share of the fender rise, but on a truck whose maker wants the front axle all the way back, a heavy tongue may not get there no matter how you turn the nuts. If the front end won't reach your target, look at a spring-bar hitch, or a lighter tongue that still sits inside your maker's range.

Reading the result: what to fix

When the numbers or the drive feel wrong, here's where each maker points first:

A tape measure has limits, and one owner's numbers show them. On a 2004 F-150 with an Andersen and a 648 lb tongue, the front wheel well read 40-1/4 in unhitched, 40-3/8 in hitched without weight distribution and 40-1/8 in with it. The owner judged the setup by the rear, which came back to within 1/4 in of its empty height. The makers measure the front, and by Equal-i-zer's formula the front came back 1/4 in on a 1/8 in rise: 200%, ending 1/8 in below its unhitched height. Equal-i-zer's 100% cap would flag that, and so would the never-lower line in GM's Colorado and Canyon manuals and Toyota's 2025 Tundra and Tacoma manuals. But a rise of 1/8 in is about as fine as a tape reads on a truck, so that percentage proves very little either way. When the front barely moves, skip the formula and weigh the truck.

Check it on a scale

Toyota's Tundra and Tacoma manuals put the scale first: return the front axle to its unhitched weight, and use the fender height only if you can't weigh the axle directly. A truck stop scale is the cheap way to do it, and three weighings tell you everything a tape can't:

1. Hitched, weight distribution on: the whole rig, front axle, rear axle and trailer axles each on its own pad.
2. Hitched, weight distribution off: unhook the bars or slack the chains in the scale lot and weigh again. Equal-i-zer's manual says to take the load off with the tongue jack before you release anything, and we'd do the same before backing off an Andersen's tension nuts.
3. Truck alone: drop the trailer and weigh the truck with the hitch head and bars on board.

The front-axle weight the trailer took off is the truck-alone figure minus the hitched, weight-distribution-off figure. The share your hitch put back is the weight-distribution-on figure minus the weight-distribution-off figure, divided by that loss. Then read the rear axle against its rating on the door-jamb label, and here GM's own manuals don't agree: the 2025 Silverado and Sierra 1500 manuals say not to exceed the rear axle rating after the spring bars are applied, and the 2025 Colorado and Canyon manuals say not to exceed it before. We'd hold every truck to the stricter version: under the rating with the bars off. If the rear axle is over its rating with the bars off, take weight out of the truck bed or the front of the trailer before you adjust anything; no setting on the hitch fixes an overloaded axle.

The scale settles the payload sum too. Every pound of tongue weight still counts against your payload, and the hitch's own weight does too: Andersen publishes under 60 lb for its hitch, and Equal-i-zer publishes no weight for its steel head and bars.

Every hookup after the first

A good setup stays good only as long as the load does. Both makers say to recheck it whenever the load in the truck or trailer changes, and Equal-i-zer wants it verified after you load for each trip. A different tow vehicle or trailer means starting over: Equal-i-zer's manual says never to move the hitch to either without adjusting it again.

• Never loosen anything under load: take the tension off with the tongue jack before you pull an L-pin or back off a tension nut. Equal-i-zer's manual builds hookup and unhooking around that rule.
• Steep grades and rough ground: Equal-i-zer says to disengage weight distribution before towing or backing across a significant change in grade, such as from a level street up a steep driveway, and not to tow engaged on rough roads, through deep ditches and dips, or while launching a boat.
• Bolts before every trip: Equal-i-zer says to check every nut, bolt, pin and clip before each trip and to look the hitch over for damage and abnormal wear; Andersen's FAQ says to inspect the friction cone before each tow.
• Electronic trailer sway control: Andersen's manual warns that some newer trucks' sway systems can work against its hitch, and our guide to whether you need weight distribution and Andersen No-Sway review cover what to check with your truck maker before you tow.
• Surge brakes: Ram's manual warns that weight distribution systems may not be compatible with surge brake couplers. Andersen says no weight distribution hitch works with them, because the hitch's forward pressure keeps them engaged, while Equal-i-zer calls its hitch compatible because the arms slide freely in the brackets.

No hitch setup removes sway altogether, and both manuals say so. If the trailer still pushes the truck around once the numbers are right, look at the tongue weight, the tire pressures and your speed before you add tension.

When the numbers won't land

If you've worked the procedure, the loaded tongue sits inside your truck maker's tongue-weight range, and the front end still won't reach your truck maker's target, the hitch may be the wrong one for the job. The Equal-i-zer 4-point moves more weight forward and gives you washers and bracket holes to do it with; the Andersen No-Sway is lighter, quieter and grease-free, and its FAQ example moves roughly 30% of the tongue weight forward. Our side-by-side comparison covers how each one hooks up and how each one fails. If the problem is a bar setup that rides stiff, check the size before you fight it: a hitch rated well above your loaded tongue weight can ride harsh however you set it.

Whichever you run, the order doesn't change. Your truck maker's manual says how much load to put back on the front axle, the hitch maker's manual says how to get it there, and the scale says whether you did. No hitch raises your truck's tow, payload or tongue-weight ratings.