Product Catalog
Gate and Dolly Casters — Spring-Loaded Gate Support and Vehicle/Frame Dolly Duty
Updated 2026-11
Gate and dolly casters solve two versions of the same problem — a wheel that must follow ground that the main structure cannot. On a gate, the caster rides at the free end, taking weight as the gate swings and the ground falls away; published fit rules put the working window at a bottom clearance of 2 to 4-3/4 inches with 2 inches or less of ground slope, and the spring does the following: an integrated spring mechanism lets the wheel move vertically to absorb bumps, dips and slopes, keeping the gate aligned and off its hinges. On a dolly, the casters carry whole vehicles or frames, and published selection guidance is equally direct: high load rated, steel framed, smooth rolling under pressure.
Our line covers spring-loaded gate caster brackets and dolly caster sets through own production and outsourcing. A published reference SKU in the class runs a 3 in x 1-1/4 in thermoplastic rubber wheel at 125 lb capacity with bolt-on or plate mount — per-SKU reference only; the rating for your gate weight or dolly load is confirmed at quotation. Lead time is 15-20 days standard, 30-40 days custom.
Specifications
| Type | Spring-loaded gate caster brackets (bolt-on / plate mount); rigid and swivel dolly caster sets (front steerable + rear trailing configurations) |
|---|---|
| Gate fit rules (industry reference) | Bottom clearance 2 to 4-3/4 in; ground slope 2 in or less; at 3-3/4 in clearance slope must be 1 in or less; mount at the gate end positioned lowest along its travel path |
| Spring function (industry reference) | Integrated spring allows vertical travel to absorb bumps, dips and slopes; maintains ground contact, keeps the gate aligned, reduces strain on hinges and mounting hardware |
| Reference SKU (industry reference) | 3 in x 1-1/4 in thermoplastic rubber wheel, 125 lb capacity, spring-loaded bracket, bolt-on or plate mount — per-SKU reference, not a family rating |
| Dolly selection rules (industry reference) | High load rated, steel framed, smooth rolling under pressure; hardened wheels that maintain shape under extreme weight |
| Lead time | 15–20 days (custom configurations 30–40 days) |
| MOQ | 200 pieces (standard catalog items ship in smaller quantities) |
| Warranty | 18 months |
Fit rules, spring behaviour and the reference SKU above are published industry references — per-SKU values are never merged into a family promise. Load ratings for your gate or dolly configuration are stated on the quotation.
Applications & Selection
The spring is the product: how gate casters follow the ground
A rigid bracket would hold the wheel at a fixed height while the gate travels an arc over uneven ground — lifting clear at dips, jamming at rises, and levering the hinge hardware at every cycle. The spring-loaded bracket replaces that fixed geometry with vertical travel: published product guidance describes the integrated spring absorbing bumps, dips and slopes while maintaining consistent ground contact, which keeps the gate aligned and reduces the strain that otherwise accumulates in hinges and mounting hardware. The same guidance adds the mounting detail most installations get wrong: position the caster at the end of the gate that sits lowest along its travel path, not symmetrically.
The fit window is published and mechanical, not a suggestion: bottom clearance from 2 to 4-3/4 inches, ground slope up to 2 inches. The two trade against each other — at a 3-3/4 inch clearance the allowed slope tightens to 1 inch or less, because the spring travel that remains after set-up height has to cover the ground variation. Measure both numbers on the installed gate before ordering; they, plus gate weight, are the whole selection.
Dolly duty: when the casters are the suspension
A dolly has nothing between the load and the wheels, so the published selection rules read like a frame specification: high load rated, steel framed, smooth rolling under pressure, with hardened wheels that maintain shape under extreme weight. Automotive guidance adds the failure picture — dollies carry entire vehicles or frames, so a wheel that deforms under standing load ruins tracking before it ruins the wheel. Divide the total load with the standard per-caster safety practice, then size wheels and frames against the divided figure, not the total.
Configuration matters as much as rating: long dollies steer from the front pair and trail a rigid rear pair; short platforms run all-swivel for tight yards or all-rigid for straight towlines. State the towing method (hand, tugger, vehicle hitch), the surface, and whether the dolly sits loaded for weeks — standing load and rolling load are different ratings, and a quote that only sees one is wrong by design.
Our path is own production plus outsourcing: standard brackets and sets ship in 15-20 days, custom springs, mounts or wheel compounds in 30-40 days, MOQ 200 pieces. Per-configuration ratings are confirmed at quotation.
Frequently Asked Questions
How do I measure my gate for a spring-loaded caster?
Two measurements decide fit, both taken with the gate installed: the clearance from the gate bottom to the ground at the mounting end, and the ground slope along the travel path. Published fit rules put the window at 2 to 4-3/4 inches of clearance with up to 2 inches of slope — and at 3-3/4 inches of clearance the allowed slope tightens to 1 inch. Add the gate weight at the caster end (the spring carries a share, not all of it, since the hinges carry the rest), and you have the three numbers a quotation needs.
Where on the gate should the caster be mounted?
At the end of the gate positioned lowest along its travel path — that is the published mounting rule. The caster must touch ground through the whole swing; mounting at the highest-travelling end leaves it useless for most of the arc, while the low end keeps the spring working within its travel. Bolt-on brackets suit tube or frame gates; plate mounts suit wood and heavy panels, and published guidance treats a four-bolt plate on a strong horizontal surface as the strongest attachment.
What load rating do dolly casters need?
Start from the total load — vehicle, frame and any cargo — and divide with the standard per-caster safety practice (a caster can be airborne on uneven ground), then add the standing-load question: a dolly parked loaded for weeks needs wheels that resist deformation under static load, which is why published guidance for vehicle dollies calls for hardened wheels and steel frames. Bring both numbers — rolling and standing — and require the quotation to state both ratings for the configuration.
Ordering & Documentation
Documents
Every order ships with a packing list and commercial invoice. Dimensional drawings (bracket plate, bolt pattern, spring travel range, wheel size) are available on request so the fit window can be checked against your measured clearance and slope before production.
Quotation
A quotation needs: gate weight at the caster end or dolly total load, measured clearance and slope (gates) or rolling and standing loads (dollies), mount type, wheel compound, and quantity. The confirmed quotation states the rating for your configuration — published class references and per-SKU figures are not the commitment.
Sample & supply
Standard brackets and sets are produced to order with an MOQ of 200 pieces; smaller trial quantities of catalog items can ship in some sizes — ask with your RFQ. Lead time is 15-20 days standard, 30-40 days for custom springs, mounts or compounds. The usual validation: cycle a sample gate through its full arc a dozen times and check ground contact at both ends; roll a loaded dolly over the worst floor section and inspect wheel shape after.
Storage & shipping
Spring brackets ship with springs at free length; store in dry cartons and keep the spring travel free of packing debris. Before installation, compress the spring by hand through its full travel — it should return without binding — and check the wheel spins freely. A caster that does not return to full extension will hang the gate short of the ground.