If you just bought a 4 post lift or you’ve had one sitting in your shop for years, the right 4 post accessories can turn a decent storage rack into a real production tool. We install and service these lifts across Iowa every week, and the calls we get most often aren’t about the lift itself — they’re about what to bolt on to it. Caster kits, slip plates, alignment kits, jack trays, extension ramps. Some of these pay for themselves the first month. Others sit in a box in the corner. We want to walk through what’s actually worth your money and what isn’t, based on what we see working in real shops.
Browse rolling jacks, caster kits, alignment packages, and slip plates built for 4 post platforms, or call us and we’ll match parts to the lift you already own.
Rolling Bridge Jacks: The First Accessory Every Shop Should Own
A rolling bridge jack, sometimes called a rolling jack or under-lift jack, rides on rails between the runways of your 4 post lift and lets you pick up a wheel or an axle once the vehicle is already up in the air. This is far and away the most requested item in our shop when someone asks about 4 post accessories, and for good reason. Without one, a 4 post lift is basically a parking spot with a view. With one, you can pull wheels, do brake work, drop a subframe, or service suspension components while the vehicle sits at a comfortable working height.
We sell these in multiple capacity ranges to match your lift, and the rail length matters more than people expect — if your bridge jack rail is too short for your runway length, you’ll fight it every time you roll it into position. We always ask what lift model you’re running before recommending a rolling jack, because fitment between brands isn’t universal. A shop we work with near Cedar Rapids added a rolling jack to a lift that had sat mostly idle for two years, and it became their primary brake and tire bay within a month.
Caster Kits and Locking Casters
Caster kits let you roll the entire 4 post lift across the shop floor, which sounds like a small convenience until you’re trying to reconfigure a bay for a big job or move a lift out of the way during a busy week. Locking casters specifically are one of the more overlooked 4 post accessories because people assume any caster kit will do. It won’t. You want casters that lock solidly in place once the lift is positioned, because a lift that creeps even a half inch under load is a liability, not a convenience.
These kits typically bolt onto the base of the runways and use a jacking mechanism to lift the whole unit off the ground for rolling, then lower it back onto its feet for use. We recommend these most for shops with multiple 4 post lifts in a shared space, detail shops that need flexible floor plans, or dealerships storing vehicles seasonally. If your lift lives in one spot forever and never moves, you can skip this one and put the money elsewhere.
Slip Plates and Turn Plates for Alignment Work
If you’re doing any front-end or four-wheel alignment work on a 4 post lift, slip plates are not optional — they’re the accessory that makes alignment possible at all. These flat plates sit under the front tires and allow the wheels to move slightly side to side and rotate as the alignment technician adjusts toe and camber. Without slip plates, the tires bind against the runway surface and you get inaccurate readings no matter how good your alignment machine is.
Turn plates take this further with degree markings for measuring steering angle, which matters for more thorough alignment diagnostics. We pair these with rear slip plates on longer runway lifts so all four corners can move freely during the adjustment process. Among 4 post accessories, this is the category where cutting corners actually costs you customers — a shop advertising alignment service without proper slip plates is going to produce inconsistent results and eventually hear about it from unhappy customers.
Jack Trays and Frame Cradle Attachments
A jack tray is a small platform accessory that mounts to your rolling bridge jack, giving you a flat surface to set a standard floor jack or transmission jack on while it’s already elevated to lift height. This saves your back and speeds up jobs where you need a secondary lift point in addition to whatever the bridge jack itself is doing. Frame cradle attachments serve a similar purpose but are shaped to cradle a frame rail or pinch weld rather than a flat pad, useful for unibody vehicles that need specific lift points.
We see these accessories used heavily in collision and body shops where precise frame positioning matters for measuring and pulling work. They’re a lower-cost addition compared to a full rolling jack replacement, and they extend the usefulness of equipment you already own. If you’re doing mixed work — some tire and brake jobs, some frame and unibody work — having both a standard jack tray and a frame cradle on hand covers you either way without needing two separate bridge jacks.
Extension Ramps and Approach Ramps
Extension ramps sit at the entry end of a 4 post lift’s runways and give longer wheelbase vehicles, lowered cars, or trucks with aftermarket bumpers a smoother approach angle onto the platform. Without them, a low front air dam or a long overhang can scrape the runway edge every single time the vehicle drives on, which is both annoying and eventually damaging to the vehicle. This is a small accessory that solves a specific, recurring headache.
We get calls about this most often from shops that service lowered trucks, sports cars, or extended-cab pickups with long front overhangs. The fix is usually a simple bolt-on or slide-in ramp extension rather than a full lift reconfiguration. It’s inexpensive relative to other 4 post accessories on this list, but if you’re turning away certain vehicles because they won’t clear your runway approach, this is the fix, not a bigger lift.
Casters, Safety Locks, and Runway Extensions Working Together
Some of the best setups we install combine several 4 post accessories rather than relying on just one. A shop doing general repair, alignment, and occasional body work might run a rolling bridge jack for daily use, slip plates permanently installed for alignment jobs, and approach ramps for the occasional low-clearance vehicle. Buying these as a package when you first install the lift is almost always cheaper than adding them piecemeal over several years, and it lets us make sure everything is rated to match your lift’s actual capacity.
We also always double-check that safety locks and lock release cables are in good working order whenever we’re out installing new attachments, since accessories only matter if the underlying lift is safe to operate. If you’ve got an older 4 post lift that’s never had any accessories added, it’s worth a call to see what would actually move the needle for your specific type of work rather than guessing. For more on matching accessories to a specific lift style, our team has also written about 4 post lift accessories in more depth, and if you’re comparing platforms, our notes on two post lift accessories can help you decide which style fits your bay better.
Matching Accessories to How You Actually Use the Lift
The mistake we see most often is shops buying 4 post accessories based on what a catalog recommends rather than what their actual daily work requires. A used car lot doing basic inspections and detailing needs different accessories than a performance shop doing alignments and suspension work, even if they’re running the exact same lift model. Before you buy anything, walk through your last month of jobs and ask which ones would have gone faster or been possible at all with a rolling jack, slip plates, or extension ramps.
We’d rather sell you the two accessories you’ll use every day than five you’ll use twice a year. When we quote 4 post accessories for a shop, we ask about vehicle types, job mix, and floor space before recommending anything, and we compare notes with what we’ve seen work for similar shops in two post lift adapters and accessories setups too, since the underlying logic of matching accessories to workflow is the same across lift styles. Call us before you buy off a spec sheet — it usually saves money in the long run.
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