AMGO RJ-8A: the bridge jack most likely to fit the lift you already own

Buying a rolling bridge jack usually means finding out afterwards whether it spans your runways. The RJ-8A is built around that problem rather than around a capacity headline. Its adjustable lower sliding assembly is described by AMGO as adjusting to fit many different brands of four-post or scissor lift, and it starts adjusting from a runway gap of 36 inches — narrower than the heavier jacks in the range will go. If your four-post came from somewhere other than AMGO, this is the model most likely to drop straight onto it.

The second thing worth knowing is how it moves. The RJ-8A uses a patented floating roller system carried inside a protective box, so the rollers run along the runway rail rather than being dragged, and they are enclosed rather than exposed to the brake dust, grit and road salt that live on a four-post platform. A bridge jack gets repositioned dozens of times a week; whether that stays easy in year three is decided by exactly this component.

Will It Fit? Measure the gap between your runways

For a bridge jack this is the whole question, and getting it wrong means the jack cannot be used at all. Measure inside face to inside face at the point along the runway where the jack will actually work, and take the measurement in two or three places rather than trusting the brochure for your lift.

• Support base width. The adjustable lower sliding assembly fits runway gaps from 36 inches to 56 1/2 inches. That lower figure is the RJ-8A's real advantage over larger jacks, which need a wider platform to sit on.
• Arm pad reach. 34 1/2 inches to 66 1/8 inches, telescoping, so the pads reach lift points across a normal spread of cars and light trucks.
• Getting it under the vehicle. The factory sheet gives a minimum height of 10 1/4 inches and a minimum rubber pad height of 10 3/8 inches. A stored field says 12.25 inches instead — see the note below.
• Lift range. 20 5/8 inches on the pads alone, rising to 29 5/8 inches with the supplied adapters fitted.
• Overall width. 21 1/2 inches.
• Air supply. A pneumatic pump running at 0.8 MPa, so you need a shop air line reaching wherever the jack is used.

Checking all of that against your own lift and your own compressor is the buyer's responsibility. We cannot see your equipment from here, and a jack that will not span your runways is not a warranty matter.

A figure that does not agree with itself

Minimum height is recorded two ways in our data: 10 1/4 inches on the factory specification, and 12.25 inches in a stored product field. Two inches is a meaningful difference when the question is whether the jack slides under a lowered car, so we are showing both rather than choosing. Ask us to confirm it before you order if your clearance is tight. Two rounded fields — a maximum width of 5.5 ft and a minimum width of 2.75 ft — also fail to reconcile with the measured 36 inch to 56 1/2 inch base range, so they are not used anywhere on this page.

Air over hydraulics, and a set of adapters that reaches high lift points

The pump is pneumatic, working from your shop air rather than from your arm. On an 8,000 lbs jack that is worth more than convenience: pumping effort scales with the load, and a hand-pumped jack under a loaded truck axle is tiring equipment that quietly stops getting used. Air over hydraulics keeps you standing beside the jack watching the pads rather than bent inside a wheel arch working a handle.

The RJ-8A comes with a full set of extension adapters — 1.5 inch, 2.5 inch and 5 inch — plus the rubber pad assemblies. AMGO's own note on why is the useful one: the taller adapters let the jack reach the lift points on pickups and higher-seated cars, where the frame or subframe pad sits well above the sill. A pad that only half meets its lift point is how sills get folded, and stacking timber is not a substitute for the adapter that came in the box.

Two locking positions and a scissor built to stay still

The jack holds height on two solid locking positions rather than one. A wheel-off brake job and an underbody inspection want the vehicle at different heights, and a single lock height forces one of the two to be done at the wrong one. The order of operations does not change on any lift: hydraulics raise the load, mechanical steel holds it, and nothing goes under the vehicle until the jack is set down onto a lock.

The scissor structure itself is described as an enhanced solid assembly for running stability, which is worth translating. A bridge jack has a loaded axle on top of a scissor linkage, and any flex there shows up as movement while somebody is putting a bar on a wheel nut. Stiffness is not about capacity — that is 8,000 lbs either way — it is about whether the vehicle feels planted while you work on it.

The guardrail earns its place twice over: it is what you push against to slide the jack along the runway, and it keeps the oil hose from being dragged across the platform edge, which is the usual way these hoses fail.

Perfect For

• Four-post lifts from any brand, which is what the adjustable lower slide is designed for.
• Narrower-runway platforms that a heavier bridge jack simply will not sit on.
• Home garages with a storage four-post wanting wheels-off capability without buying a second lift.
• Alignment and tyre bays needing wheels free without taking the vehicle off the rack.

What's in the Box

From AMGO's own feature list: the pneumatic hydraulic pump, extension adapters in 1.5 inch, 2.5 inch and 5 inch sizes with their rubber pad assemblies, the telescoping arms, the patented floating roller system in its protective box, the adjustable lower sliding assembly and the guardrail. If you want the crate contents confirmed item by item before ordering, ask us and we will read them off the current packing list rather than guess.

Specifications

Certification, stated plainly

Our record for this product does not state a third-party safety listing of any kind. That is missing information rather than a statement by the manufacturer either way, and saying so is more useful to you than an implication. In a private garage the question rarely arises. It does arise for some commercial insurance policies, for fleet and municipal operations, and for jurisdictions whose code names a specific listing. If that applies to you, ask us before ordering and we will put the question to the manufacturer in writing rather than answer it from a sales sheet.

Shipping and delivery

This ships by freight truck to addresses in the lower 48 states, with freight quoted live at checkout against your own address, so the figure you see is a current carrier rate rather than a stale estimate. It arrives crated on a standard trailer and getting it to the ground is the receiver's job — a forklift, a machine, or a plan and some help. Where none of those exist, collecting from the carrier's local terminal is usually easier, because the terminal already has the equipment. Delivery to a residential address carries a residential fee, applied at checkout when you select it.

Inspect before you sign: crushed corners, bent steel, shifted banding, any trace of oil. Write what you find on the bill of lading while the driver is still there, and photograph it. A clean signature is the carrier's evidence that the load arrived undamaged.

Warranty

AMGO publishes a written warranty covering this product and we hold the document rather than a summary — ask us for the current copy before ordering if the terms matter to your decision. One warning applies to every hydraulic lift whoever built it: if something fails, do not open the power unit, a cylinder or a lock mechanism before a claim is raised. A disassembled component is normally treated as a modified one, and that is the quickest way to lose cover that would otherwise have been paid. Photograph the fault, note the serial number, and call us first.