Setting up a weight distribution hitch is a measurement job. You measure the truck's front fender height unhitched, hitch up with the bars off, then tension the bars until the front comes back down to the height your truck maker specifies for your truck.
Setting Up a Weight Distribution Hitch: Measurements, Bar Tension and the Check
At a glance
- Ford prints a Weight Distribution Correction Factor of 50% for the 2026 F-150 and the F-250/F-350 Super Duty pickup: take back half of the front-end rise.
- GM's 2026 Silverado/Sierra 1500 supplement asks for half of the rise; the 2500 HD/3500 HD supplement asks for a quarter.
- Ram's 2026 procedures leave the front fender approximately a third of the rise above its unhitched height.
- Both vehicles are loaded as they will travel, water and propane included, on level ground, before any measurement is taken.
- The confirmation GM asks for is a scale: the rear axle at or under its rating with the spring bars applied.
On this page (9)
What the setup is actually measuring
Two numbers drive everything. H1 is the front fender height with the trailer unhitched. H2 is the same measurement with the trailer coupled and no spring bars attached. The difference between them is the front-end rise the tongue caused, and the bars' job is to take back a specified share of it.
Ford's procedure in the 2026 Ford RV & Trailer Towing Guide (page 8) runs in this order:
- Load the trailer as it will be loaded for the trip, with 10% tongue weight, and park on level ground.
- Adjust the tongue jack until the trailer is level or just slightly nose down.
- Load the tow vehicle as it will be used for the trip and park it on level ground.
- Adjust and secure the weight distribution ball mount so the tow ball is at the same height as the trailer coupler, with the trailer uncoupled.
- Measure from the top of the front fender lip above the wheel center to the ground. Record it as H1.
- Couple the trailer with no bars attached and the tongue jack fully retracted, then measure again. Record it as H2.
- Adjust the bars per the hitch maker's instructions until the fender lip reaches the Target Height, with the trailer still level to slightly nose down.
- Complete coupler latching, electrical connections, safety chains and the breakaway attachment.
Ford's own worked example for an F-150: H1 of 37 inches, H2 of 38 inches, correction factor 50%. The height change is 1 inch, the reduction is 1 inch times 50%, or 0.50 inch, and the Target Height is 38 minus 0.50, which is 37.5 inches.
How much of the rise to take back, by truck
This is where trucks differ, and where most bad setups come from. The percentage is not a hitch specification. It is a truck specification, and it varies by brand, by duty class and in one Ford case by cab style.
| 2026 vehicle | Target front fender height with bars engaged |
|---|---|
| F-150 Pickup, F-150 Raptor Pickup | H2 minus 50% of (H2 minus H1) |
| F-250/F-350 Super Duty Pickup | 50% correction factor; Ford's Super Duty notes state it recommends 50% front axle load restoration when using load bars |
| F-450 Super Duty Pickup | 25% Regular Cab, 50% Crew Cab |
| Expedition, Super Duty Chassis Cab (all) | 50% |
| Mustang, Bronco Sport, Escape, Bronco, Explorer, Maverick, Ranger | Not required |
| Silverado 1500 / Sierra 1500 | H2 minus [(H2 minus H1)/2], half way between the two measured ride heights |
| Silverado / Sierra 2500 HD and 3500 HD | H2 minus [(H2 minus H1)/4], a quarter of the difference below H2 |
| Ram 1500 with air suspension; Ram 2500/3500 with or without air suspension | (H2 minus H1)/3 plus H1, approximately a third of the difference above unhitched height |
Figures from the 2026 Ford towing guide page 8, the 2026 Silverado 1500 / Sierra 1500 Trailer Towing Supplement, the matching 2500 HD/3500 HD supplement, and the 2026 Ram 2500/3500 owner's manual. Ford's table also lists Transit as "use not recommended".
Ram states its target the other way around, as the height left above H1 rather than the share removed. Leaving a third of the rise above unhitched height means roughly two thirds of the rise has been taken back; that two-thirds figure is our arithmetic from Ram's formula, not a number Ram prints.
Note also that the 2026 and 2025 Ram 1500 manuals print only the air-suspension procedure, which runs with tire service mode enabled and then switched back off to confirm the truck returns to normal ride height.
Tip: Hitch manuals print their own band, and it does not always contain your truck's number. The Equal-i-zer 6K to 14K manual targets 50 to 100% weight distribution and tells you to refer to the tow vehicle owner's manual for exact ratings. A GM heavy duty's 25% sits below that band. The truck maker's figure wins, and Equal-i-zer itself says so.
Before you start
Equal-i-zer's Step 1 sets the conditions: park trailer and tow vehicle on flat, level ground and in line with each other, chock the trailer, and load both just as they will be while traveling, including propane, water, generators and cargo. Tires inflated to pressure. Auto-level systems disabled or turned off temporarily.
You need the instruction sheet for your exact hitch model, since what a weight distribution hitch does is the same across designs but the adjustment hardware is not. A tape measure, and a torque wrench that reaches the figures in your sheet.
The Equal-i-zer 6K to 14K manual lists a wrench capable of 320 ft-lbs with a 1 1/8 inch socket for the shank bolts, and one capable of 430 ft-lbs with a 1 7/8 inch thin-walled socket if you are fitting an Equal-i-zer hitch ball.
Suspension that levels itself has to be handled first. CURT's 17500 manual says that unless the vehicle manual indicates otherwise, air springs and air shocks should be deflated to their minimum recommended pressure before the hitch is assembled and adjusted.
Equal-i-zer's manual for its 6K to 14K hitches states that four-corner auto-leveling decreases weight distribution by 20 to 25%, and that if it cannot be left off while driving, the hitch should be set to 75 to 100%. With rear-only auto-leveling, let the vehicle level before taking the final measurement.
Ball height and head tilt
Ball height sets how the trailer sits and how much tension the bars can develop. The makers do not agree on the starting figure, so use the sheet that came with your hitch.
| Document | Uncoupled ball height relative to the coupler |
|---|---|
| 2026 Ford towing guide | Same height as the trailer coupler, trailer uncoupled |
| Equal-i-zer 6K to 14K manual | Top of the ball 0 to 1 inch above the top of the coupler; start with 6 spacer washers for most setups |
| CURT 17500 TruTrack | Above the measured coupler height to allow for squat; for cars, vans and small SUVs add 1/8 inch per 100 lb of tongue weight (CURT prints no figure for pickups) |
| Weigh Safe True Tow | Rule of thumb 1/8 inch higher per 100 lb of tongue weight, depending on suspension |
| Blue Ox Airstream SwayPro | Same height or 1 inch higher; Ram owners referred to the Ram manual, with 2 inches higher recommended for towing performance |
Figures quoted from each maker's current instruction sheet or manual as listed. CURT's 17051 round bar sheet adds a hard limit: the loaded ball height should never be greater than the uncoupled ball height, because front wheel overload and loss of rear wheel traction can follow.
On trailer attitude, GM is the strictest: always level the trailer front to back with the correct drawbar, and do not attempt to tow a trailer that is not level, since an unlevel trailer loads its own axles, springs and tires wrongly. Ford allows level to slightly nose down. Equal-i-zer's own tolerance is a front-to-rear frame measurement within 1 1/4 inches, re-checked after weight distribution is set.
Head tilt is the coarse control on bar tension. CURT says that if the tow vehicle cannot be leveled at the initial Position 1 head setting, increase the tilt position, which allows more tension on the arms.
Engaging the bars and adjusting
With ball height set and the trailer coupled, the sequence on an L-bracket hitch such as the Equal-i-zer runs like this:
- Use the tongue jack to lift both vehicles until the spring arms swing onto the L-brackets, using the snap-up lever if needed, and insert the L-pins.
- Retract the jack until the full weight of the tongue is on the hitch.
- Check there is at least 3 inches from the end of each spring arm to the center of the L-bracket. Less than that, and the brackets must be moved forward.
- Measure the front fender again and work out where you landed against your truck maker's target.
- If it is off, raise both vehicles with the jack, unload and remove the arms, unhitch, change the number of spacer washers or the L-bracket position, re-hitch, engage, retract the jack and measure again.
- Repeat until the measurement meets the target.
Chain-type hitches adjust differently. CURT's round bar sheet says to add chain links between the lift bracket and the spring bar if the front has settled much more than the rear, with at least five links in use and the same count on both sides, and the spring bars nearly horizontal when the height is right.
On the TruTrack, the fix for the same symptom is to lower the L-brackets. Blue Ox's SwayPro instructions have you adjust the chains one link at a time until the tow vehicle is level, with bars designed to deflect 2 to 3 inches on a properly set system.
Tip: Equal-i-zer asks for both wheel wells to be measured and averaged, not just the driver's side, because a crowned surface or uneven load skews a single reading. Mark the chain at the hooked link with paint once the setup is right, as CURT advises, so the next hook-up starts from a known position instead of a guess.
Confirming it on a scale
Ride height tells you the setup matches the target. It does not tell you the axles are legal. GM states plainly that the only way to be sure the weight ratings are not exceeded is to verify with a scale, and that with a weight-distributing hitch the rear gross axle weight rating must not be exceeded after the spring bars are applied, with truck and trailer fully loaded for the trip. The ratings you are checking against are printed on your own truck's certification label in the driver's door jamb.
Ford's method for getting axle weights with a trailer attached: place the front wheels of the vehicle on the scale for front gross axle weight, then weigh the towing vehicle with the trailer attached but with just the vehicle's four wheels on the scale, and subtract the front figure to get the rear.
The total load on each axle must never exceed its rating. Ram's loading section asks for the whole vehicle weighed first against GVWR, then front and rear determined separately.
CAT Scale describes the straightforward layout: steer axle on platform 1, drive or rear axle on platform 2, trailer on platform 3, which returns axle weights and gross weight but not individual wheel weights. Note what no maker does: none of Ford, GM or Ram describes a three-pass weighing routine for checking a weight distribution hitch, and none prescribes a front-axle weight the ticket should show. Forum routines that do are not manufacturer procedure.
Tip: CAT's published prices, read on 2 October 2026, are $15.25 for a full-price weigh and $5.25 for a reweigh, if it is the same vehicle at the same scale within 24 hours and you present the full-price ticket so its number can be recorded. The rule is written for tractor-trailers, so ask at the counter before assuming an RV combination qualifies.
Torque, and the re-check after the first miles
Final tightening comes after the distribution and trailer pitch are right, not before. Values are model-specific, so take them from your own sheet rather than a general table.
| Hitch | Published torque |
|---|---|
| Equal-i-zer 6K to 14K (90-00-0600 to 90-00-1400) | 3/4 inch shank bolts 320 ft-lbs; 1/2 x 3 1/2 inch link plate bolts 65; 1/2 x 1 1/2 inch L-bracket bolts 75; socket bolts 60 minimum, 100 maximum; angle set bolt against the shank plus half a turn |
| Equal-i-zer 4K (90-00-0400) | 5/8 inch shank bolts 180 ft-lbs; 3/8 x 3 1/4 inch link plate bolts 27; 7/16 x 1 1/4 inch L-bracket bolts 45 |
| CURT 17500 TruTrack | Castle nuts 75 lb-ft; support bracket nylock nuts 25 lb-ft; 3/4 inch head bolts and nylock nuts 200 lb-ft once tilt is set |
| CURT 17051 round bar | 3/4 inch bolts and locknuts 200 ft-lbs; 5/8 inch hex head set screw 50 ft-lbs; 1/2 inch head attachment bolts 75 ft-lbs |
| Weigh Safe True Tow | Clamp bolt 35 to 65 ft-lbs; trailer bracket bolts 65; spring arm swivel bolts 60 to 150; slider bolts 150 to 320 |
Values as printed in the Equal-i-zer 6K to 14K and 4K owner's manuals, the CURT 17500 and 17051 installation sheets, and the Weigh Safe True Tow manual.
Two makers print two numbers for the same fastener. The Blue Ox Airstream SwayPro manual calls for 250 ft/lbs on the 3/4-10 head bolts at installation and 257 ft/lbs in its re-installation step. Equal-i-zer's manual gives socket bolts as 60 minimum and 100 maximum, while its web owner's guide says 65 ft-lbs. Use the sheet that shipped with your hitch, name which document you followed, and do not average two figures into a third that nobody published.
For the re-check, Equal-i-zer's owner's guide heading covers the first 50 to 100 miles of towing: re-check weight distribution, lubricate the head and ball, and check that every bolt is tight.
The same page notes that on a new hitch the angle set bolt may need re-tightening after the first 150 miles, turned back into contact with the adjustable shank then half a turn more. Beyond that, Equal-i-zer, Blue Ox, CURT and Weigh Safe all ask for a hardware check before each tow; CURT's round bar sheet puts it at the beginning of every tow day.
Hardware limits matter as much as torque. Equal-i-zer says never to cut, weld, grind, bend or modify hitch components. Ford notes that weight-distributing hitch platforms are welded or bolted to the frame, and recommends bolt-on types partly because a properly installed bolt-on platform should not weaken the vehicle or underbody as welding heat might.
Anything structural on the receiver, the frame or a mounting bracket, including welding, is a job for a licensed hitch installer; Ram simply states that all trailer hitches should be professionally installed.
When the setup has to be redone
The numbers you recorded apply to one load. Equal-i-zer makes the operator responsible for verifying the hitch is adjusted correctly after loading trailer and tow vehicle for each trip, and points out that a weekend of dry camping with full water and propane loads differently from a hookup site. Blue Ox says the spring bar chains may need adjusting if trailer or axle weight has changed since the last trip.
A change of vehicle or trailer means a full redo, not a transfer: Equal-i-zer states that a hitch should never be moved to a different tow vehicle or trailer without re-adjusting it for proper setup and weight distribution. Once the hitch is right, the next item in the chain is the brake controller and its gain setting. General towing safety background is published by NHTSA.
Common questions
How do I know if my weight distribution hitch is set up correctly?
Compare the front fender height with the bars engaged against your truck maker's target. On a 2026 F-150 the target is H2 minus half of the rise from H1 to H2; on a 2026 Silverado 1500 or Sierra 1500 it is half way between the two heights; on a 2026 Silverado 2500 HD or 3500 HD it is a quarter of the difference below H2; on a 2026 Ram 1500 with air suspension or a Ram 2500/3500 it is about a third of the difference above H1. Then confirm on a scale that the rear axle is at or under its rating with the bars applied, as GM requires.
How tight should weight distribution bars be?
Tight enough to hit that fender height, and no tighter. The Equal-i-zer 6K to 14K manual frames the same thing as a percentage: 50 to 100% weight distribution, never above 100%. Under-distributing leaves too much weight on the rear axle, which Equal-i-zer links to loss of steering and braking control and less sway resistance; over-distributing can remove too much weight from the rear axle and cause loss of traction and jack-knifing on slick roads. Where that band conflicts with your truck's published figure, as it does on GM heavy duty trucks at 25%, follow the truck.
Should the trailer be level with a weight distribution hitch?
GM's 2026 Silverado 1500 and Sierra 1500 supplement says to always level the trailer front to back using the correct drawbar, and not to tow a trailer that is not level, because an unlevel trailer loads its axles, springs and tires incorrectly. Ford's setup procedure allows level to slightly nose down. Equal-i-zer's practical tolerance is a difference of no more than 1 1/4 inches between front and rear frame measurements, with ball height adjusted if it exceeds that.
Do I set up a weight distribution hitch loaded or empty?
Loaded, as it will travel. Equal-i-zer's first step calls for both vehicle and trailer loaded just as they will be while traveling, including propane, water, generators and other cargo, on flat level ground with the trailer chocked. Ford's steps 1 and 3 say the same for trailer and tow vehicle. A hitch set up on an empty trailer will not meet the target once the fresh water tank is full.