Ball mounts and drop hitches
CURT adjustable channel mount review
An adjustable ball mount solves the same problem a shelf full of fixed mounts used to: one part instead of several, set to the drop or rise a specific truck and trailer pairing actually needs. A channel-style mount does that with a sliding dual-ball head pinned into a drop channel rather than a single fixed hole.
The CURT 45900 is the 2 inch receiver version of that design. This review covers what CURT actually publishes for it, the one convenience it does not offer compared to a stowable mount, and when the 2-1/2 inch version or a fixed mount fits better.
On this page
- What is the CURT 45900, and what does CURT actually publish for it?
- How does the 45900 compare against the heavier-duty CURT 45902, a stowable B&W mount and the Rhino USA adjustable hitch?
- What does CURT actually publish for the 45900?
- What is the catch with a channel-style adjustable mount?
- What are the alternatives if channel adjustment is not the right fit?
- What should you check before buying an adjustable channel mount?
What is the CURT 45900, and what does CURT actually publish for it?
The 45900 fits a 2 inch by 2 inch receiver tube and can be flipped in the channel for up to 5-1/4 inches of rise or 6 inches of drop, adjusted through the channel pin holes rather than by a continuous slide. CURT rates the 2 inch ball at 10,000 lb and the 2-5/16 inch ball at 14,000 lb, limited by whichever component in the setup is rated lowest. Two hitch pin holes on the shank itself give a choice of 11 inch or 12 inch overall length for extra clearance behind a spare tire or a bumper.
How does the 45900 compare against the heavier-duty CURT 45902, a stowable B&W mount and the Rhino USA adjustable hitch?
All four of these adjust for drop or rise. What actually separates them is receiver size, published ball ratings and whether the mount tucks away when nothing is hitched.
| Published rating | CURT 45900 Adjustable Dual-Ball Channel Mount, 2 inch shank, 6 inch drop | CURT 45902 Adjustable Dual-Ball Channel Mount, 2-1/2 inch shank, 6 inch drop | B&W Tow & Stow Adjustable Ball Mount, 2-1/2 inch receiver, dual ball | Rhino USA Adjustable Trailer Hitch, 2 inch receiver, 6 inch drop or rise |
|---|---|---|---|---|
| Price | $194.74 | $268.74 | $309.00 | $199.90 |
| Receiver size | 2 | 2-1/2 | 2-1/2 | 2 |
| Ball diameter | 2 and 2-5/16 | 2 and 2-5/16 | 2 and 2-5/16 | not published |
| Drop | 6 in | 6 in | not published | not published |
| Adjustable drop range | not published | not published | not published | 6 in |
| Mount type | Adjustable channel | Adjustable channel | Adjustable, stowable | not published |
Every figure here is the manufacturer's own published rating. A blank is a figure the maker does not publish, and we leave it blank rather than estimating it. The rating stamped on the part you actually receive is what governs.
What does CURT actually publish for the 45900?
CURT rates the 45900 for a 2 inch receiver with a 2 inch ball at 10,000 lb GTW and a 2-5/16 inch ball at 14,000 lb GTW.
Published standard A published, traceable figure: a standards body, a federal regulation or a manufacturer specification states it.
| Published spec | CURT 45900 |
|---|---|
| Receiver size | 2 in |
| Maximum drop | 6 in |
| Maximum rise | 5-1/4 in |
| 2 in ball rating | 10,000 lb GTW |
| 2-5/16 in ball rating | 14,000 lb GTW |
| Shank length options | 11 in or 12 in |
Ratings are limited by whichever part of the setup is rated lowest, not by the ball alone.
What is the catch with a channel-style adjustable mount?
The 45900 does not stow away. The channel body, the dual-ball insert and the pins that hold it together stay assembled in the receiver, or have to be pulled apart by hand and stored, unlike a stowable design that rotates flush against the underside of the vehicle. That is a real tradeoff for a mount that otherwise does the same core job at a lower price: more loose parts to keep track of, and nothing to prevent it from sitting at shin height in the receiver between trips.
The second thing worth knowing is that CURT ball ratings on this mount are per-ball figures rather than a single number for the mount itself. The 2-5/16 inch ball carries a materially higher rating than the 2 inch ball on the same head, so which ball is actually installed changes what the mount is rated for.
What are the alternatives if channel adjustment is not the right fit?
A reader who wants the stow-away convenience and does not mind the higher price should step up to the B&W Tow & Stow. A reader towing behind a 2-1/2 inch Class V receiver needs the CURT 45902 instead, the same channel design rated to 20,000 lb GTW on the larger ball. A reader whose drop or rise is fixed and already known should skip adjustability altogether: the CURT 45036 and the CURT 45041 ship pre-torqued with the ball installed, at a fraction of any adjustable mount price.
What should you check before buying an adjustable channel mount?
Work out the actual drop or rise the truck and trailer pairing needs using the hitch drop calculator before assuming a 6 inch range covers it, since a mismatch either direction changes how much tongue weight actually reaches the axle. Read the ball mount drop or rise guide for the level-tow target, check the ball size against the hitch class chart, and compare against a stowable design in the B&W Tow & Stow review before deciding which tradeoff fits.
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.
Sources
- CURT published specifications for the 45900 and 45902 channel mounts
- B&W published specifications for the Tow & Stow dual-ball mount
- Rhino USA published specifications for the adjustable trailer hitch
Frequently asked questions
What receiver size does the CURT 45900 fit?
The 45900 fits a 2 inch by 2 inch receiver tube. A truck with a 2-1/2 inch Class V receiver needs the CURT 45902 instead, which uses the same channel design rated to a higher GTW on its larger ball.
What is the maximum drop on the CURT 45900?
CURT rates the 45900 for up to 6 inches of drop or 5-1/4 inches of rise, depending on which way the channel is flipped in the receiver and which pin hole is used on the shank. Two shank pin holes also give a choice of 11 or 12 inch overall length.
Does the CURT 45900 stow away when not towing?
No. The channel body and dual-ball insert stay assembled in the receiver or have to be removed by hand. A reader who wants a mount that rotates and tucks away on its own should compare the B&W Tow & Stow instead, at a higher price.
What is the towing rating of the CURT 45900?
CURT rates the 2 inch ball at 10,000 lb GTW and the 2-5/16 inch ball at 14,000 lb GTW on the same head. The overall setup is always limited by whichever component, hitch, mount or ball, carries the lowest published rating.
Is the CURT 45900 cheaper than a stowable ball mount?
Yes. It carries a lower published price than the B&W Tow & Stow while covering the same adjustable height range and dual ball sizes. The tradeoff is that it does not tuck away into the receiver the way a stowable design does.
Does the CURT 45900 raise my towing capacity?
No. An adjustable ball mount only sets the height at which the trailer tows level. It does not change payload, GVWR, GCWR or any axle rating on a specific vehicle, which are set only by that vehicle own door jamb sticker and owner manual.
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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.