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Ball mounts and drop hitches

Which adjustable ball mount actually gets you level?

Last updated Researched from published standards and manufacturer guides, not tested in person

Quick answer

An adjustable ball mount lets one part cover a range of receiver heights instead of buying a fixed part for one measurement. The CURT 45900 flips for up to 6 inches of drop or 5-1/4 inches of rise on a 2 inch receiver for $194.74, and getting within about 1 inch of level, measured with the truck loaded, is the actual target.

The entire job of a ball mount is to put the ball at the height that makes the trailer frame level once it is hitched, and an adjustable mount simply lets one part cover a range of heights instead of committing to a single fixed measurement. That matters because the correct drop or rise changes with the load: a truck sitting on stock springs, a truck with a lift, and the same truck loaded for a trip can each want a meaningfully different number from the same receiver.

Nose height is not cosmetic. Tow the trailer nose high and the load shifts rearward onto the trailer axle, which reduces tongue weight at the exact moment the trailer is already less stable, because a lighter tongue is the sway condition. Tow it nose low and the load shifts forward, overloading the front trailer axle and the tow vehicle rear axle instead. Neither error is subtle once you know what to look for, and both are avoidable with a single accurate measurement.

Measure the receiver height with the tow vehicle loaded the way you actually tow it. A loaded truck sits lower than an empty one, sometimes by more than an inch, and an inch is the entire tolerance you are working with. Measuring an empty truck in the driveway and buying a mount to that number is the single most common way an otherwise correct adjustable mount still tows nose high.

On this page
  1. Beginner: real adjustment on a 2 inch receiver, no premium features
  2. Intermediate: reversible drop or rise with a lifetime guarantee
  3. Expert: adjustable height that also stows out of the way
  4. What actually happens when the trailer is not level?
  5. How do you measure the drop or rise you actually need?
  6. Adjustable mounts compared
Beginner First rig: the lowest total cost to a combination that tows safely.

Beginner: real adjustment on a 2 inch receiver, no premium features

This tier buys the adjustment range that fixes nose-high and nose-low towing, without paying for a stow feature or a second receiver size you may not need.

Intermediate Committed: the buy-once pick, where the money stops being wasted.

Intermediate: reversible drop or rise with a lifetime guarantee

The value pick here is about buying once. A reversible mount that covers drop and rise on the same part removes the chance of ordering the wrong direction entirely.

Expert The performance ceiling, and who should not buy it.

Expert: adjustable height that also stows out of the way

Who should not buy this tier: Any truck with a plain 2 inch receiver. This specific mount and its tri-ball sibling are both built on a 2-1/2 inch shank for a Class V receiver, so a half ton truck with a standard 2 inch opening needs the CURT 45900 or the Rhino adjustable mount above instead, not a version of this one.

What actually happens when the trailer is not level?

Nose high moves load onto the trailer axle and reduces tongue weight, which is the sway condition. Nose low overloads the front trailer axle instead.

Rule of thumb Widely taught towing convention rather than a published specification. It is a good starting point and it is not a rating.

Nose height and what it does to tongue weight
Trailer attitudeWhat happens to tongue weightWhat it means
Level, within about 1 inchStays at what you loaded forThis is the target
Nose highFalls, load shifts rearward onto the trailer axleThe sway condition. Fix the mount, not the loading.
Nose lowRises, load shifts forward onto the tongue and front trailer axleOverloads the tow vehicle rear axle and the front trailer axle

The 1 inch tolerance is towing convention taught by hitch makers, not a published engineering standard. Treat it as the practical target rather than a hard limit.

How do you measure the drop or rise you actually need?

  1. Load the tow vehicle the way you actually tow. Passengers, cargo and a full tank if that is how you travel. An empty truck sits noticeably higher than a loaded one, sometimes by more than the entire 1 inch tolerance you are working with.
  2. Measure the receiver on level ground. From the ground to the top inside edge of the receiver tube opening. Write this number down.
  3. Measure the coupler at level. With the trailer frame level, from the ground to the bottom of the coupler. This is usually done with the trailer on its jack before it is ever hitched.
  4. Subtract the two figures. If the receiver measurement is larger, you need a drop of that difference. If the coupler measurement is larger, you need a rise of that difference.
  5. Buy to the nearest stocked size, or buy adjustable. Fixed mounts come in whole and half inch steps. An adjustable mount removes the need to land on an exact stocked size and gives you room to correct for a different trailer later.

Adjustable mounts compared

The CURT 45900 Adjustable Dual-Ball Channel Mount, 2 inch shank, 6 inch drop and Rhino USA Adjustable Trailer Hitch, 2 inch receiver, 6 inch drop or rise both cover 2 inch receivers, while B&W Tow & Stow Adjustable Ball Mount, 2-1/2 inch receiver, dual ball steps up to a 2-1/2 inch Class V shank.

Published standard A published, traceable figure: a standards body, a federal regulation or a manufacturer specification states it.

Adjustable ball mounts by receiver size and range
MountReceiver sizeDrop or rise rangeBall sizesPrice
CURT 45900 Adjustable Dual-Ball Channel Mount, 2 inch shank, 6 inch drop2 inchUp to 6 in drop, 5-1/4 in rise2 and 2-5/16 inch$194.74
CURT 45902 Adjustable Dual-Ball Channel Mount, 2-1/2 inch shank, 6 inch drop2-1/2 inchUp to 6 in drop, 5-1/4 in rise2 and 2-5/16 inch$268.74
Rhino USA Adjustable Trailer Hitch, 2 inch receiver, 6 inch drop or rise2 inchUp to 6 in either direction2 and 2-5/16 inch$199.90
B&W Tow & Stow Adjustable Ball Mount, 2-1/2 inch receiver, dual ball2-1/2 inchAdjustable, stows when not towing2 and 2-5/16 inch$309.00

A receiver, ball mount, ball and shank each carry their own rating, and the assembled hitch is limited by whichever is lowest. Confirm your own receiver rating before buying to a bigger number.

How we chose

We did not test this hardware in person and we never claim to. Picks are researched from manufacturer specification sheets, published towing standards, and the recurring themes in verified owner reviews. Every pick is matched to a real gross trailer weight rating, a real tongue or pin weight rating, a real receiver size or a real load index rather than to a price bracket, and it is placed in the tier where its published capability actually belongs. We rejected the unbranded flood that dominates the search results in several of these categories, because a weight distribution hitch, a brake controller, a trailer tire and a set of safety chains are all parts whose failure puts a loose trailer on a public road. Where a figure is towing convention rather than a published standard we label it that way, and where a manufacturer does not publish a figure we leave it out instead of estimating it.

Frequently asked questions

What counts as level enough when towing?

Within about 1 inch of level, measured trailer frame to ground front and back. This is towing convention taught by every hitch maker rather than a published engineering tolerance, but it is a reliable practical target. Being level keeps both trailer axles sharing load as designed and keeps your tongue weight at the percentage you actually loaded for.

Why does towing nose high reduce tongue weight?

Because raising the nose shifts the trailer center of mass rearward, toward the trailer axle and away from the ball, which both lengthens the pendulum the trailer hangs from and reduces the downward force at the hitch. That combination is what starts trailer sway, so a nose-high trailer is not just an unattractive stance, it is the specific geometry that makes sway more likely.

Do I need to measure the receiver height loaded or empty?

Loaded, the way you actually tow. A loaded truck sits measurably lower than an empty one, sometimes by more than an inch, and the entire tolerance you are working within for level towing is about an inch. Measuring an empty truck in the driveway is the single most common reason an otherwise correctly bought ball mount still tows nose high.

Can one adjustable ball mount replace several fixed ones?

Often, yes. An adjustable mount covering a real range of drop or rise, plus two ball sizes on the same head, can replace what would otherwise be several single-purpose fixed mounts bought for different trailers or a truck that changes ride height. It costs more up front and pays that back the first time a second trailer or a lift kit changes your numbers.

Is a higher rated ball mount always the safer choice?

No. Match the mount to your actual tongue weight and receiver rating rather than buying the largest number on the shelf. The receiver itself is frequently the true ceiling on a half ton truck, and a mount rated well beyond the receiver does not raise what the receiver, the vehicle payload or the GVWR can actually carry.

Does the correct drop change if I switch trailers?

Yes, almost always, because a different trailer has a different coupler height. This is exactly the case an adjustable mount is built for: re-measure the coupler height for the new trailer, keep the same receiver measurement from your truck, and adjust the mount rather than assuming the old fixed setting still applies.

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Researched, not professional advice. This page is compiled from published standards, manufacturer towing guides and product specifications, and owner-review consensus, not hands-on testing. Figures described as a rule of thumb are towing convention rather than published standards, and they are labelled that way wherever they appear. Nothing here overrides your own ratings. Work your payload sum before your tow rating, because payload is the limit that actually binds on most half ton trucks and nearly every SUV. Load a conventional trailer to 10 to 15 percent tongue weight and a fifth wheel to 15 to 25 percent pin weight, and never lighter: a tail heavy trailer is what starts sway. Weigh the rig loaded rather than trusting a brochure dry weight. A weight distribution hitch and a set of air bags both restore ride height and control, and neither one raises a single rating. Trailer brakes are required by state law above a threshold that varies by state, and a breakaway battery that has quietly gone flat is the normal condition of most trailers on the road.