One Year With a 2 Post Car Lift: Spec Comparison and Tire Work at an RV Shop

A 2 post car lift was not the first thing an RV and trailer service shop along the Iowa-Illinois corridor thought it needed, and that is exactly why the story is worth telling. The shop had drive-on ramps, a pile of bottle jacks, and two guys whose knees were shot from crawling under tow vehicles all day. Tire rotation on a dually pickup took forty minutes. Wheel bearing work on a tandem-axle trailer meant blocking, cribbing, and praying. We spent a spring measuring their bays, comparing model numbers across three capacity classes, and finally set two columns in concrete. Twelve months later, here is what actually mattered and what turned out to be noise.

Why an RV shop went with two columns instead of four

Four-post lifts get recommended to RV and trailer shops constantly, and for storage or long-wheelbase alignment work that advice is fine. But this shop’s daily bread was wheels, brakes, bearings, and suspension on the tow vehicles and the trailers hooked behind them. Anything that puts runways under the tires blocks exactly the work they get paid for. That is the whole argument in one sentence: if the wheels need to hang free, you want the vehicle held by its frame, not its tires.

The second factor was floor space. Their two main bays are 24 feet deep with a loft over one side, and a four-post eats that footprint permanently whether a vehicle is on it or not. Columns give the floor back. When a fifth-wheel comes in for a chassis inspection, they pull the arms in tight and roll a floor jack right past. We have installed both types in shops all over eastern Iowa and western Illinois, and the pattern holds: general repair leans two-post, storage and alignment lean four-post. The shop also liked that the columns doubled as a lighting and reel mount, which sounds trivial until you have run air lines across an open bay for a decade. A year in, nobody has asked us about adding runways.

Capacity: why 10,000 lb was the wrong answer here

The first quote we wrote was for a 10,000 lb symmetric unit, because that is what most shops buy and it covers the vast majority of light vehicles. Then we actually weighed what rolls through their door. A three-quarter-ton diesel pickup with a service body and a full fuel tank was pushing 9,200 lb on their scale. Add a toolbox, a generator, and a hitch, and the margin evaporates. Rated capacity is not a target to hit; it is a ceiling you stay well under.

We moved them to a 12,000 lb class machine with wider column spacing and longer arms. The cost difference between capacity tiers on a 2 post car lift is real but smaller than people assume once you factor freight and install into the same trip. What is not smaller is the difference in arm reach. On the 12,000 lb unit the rear arms extend far enough to reach the frame pickup points on a long-bed crew cab without stacking adapters like a Jenga tower. That single spec has saved them more time than any other feature. If your heaviest regular vehicle is 6,000 lb, a 9,000 or 10,000 lb machine is honest and appropriate. If you are guessing, guess up one tier. We have never once had a shop call us a year later wishing they had bought less capacity, and we have taken plenty of calls going the other direction.

Clearfloor versus baseplate: the ceiling decides

This is the spec that gets settled by a tape measure, not preference. A clearfloor design routes the equalization cables and hydraulic hose through an overhead beam, which means nothing crosses the floor and you can sweep the bay clean. The tradeoff is height: you need enough clearance for the beam plus the shutoff bar plus whatever you intend to raise underneath it. Fourteen feet is comfortable. Twelve is tight. Under twelve and you are limiting yourself before you start.

Baseplate models run everything through a low channel between the columns. You lose the clean floor and gain every inch of vertical room. We get calls constantly from people with a 139-inch maximum height or a garage door track in the way, and baseplate is almost always the answer for them. The RV shop had 15 feet of clear ceiling in their main bay, so overhead was easy. But their second bay has ductwork at 11 feet 4 inches, and when they add a second 2 post car lift next year it will be a baseplate unit, no debate. One warning we give everyone: measure to the lowest obstruction in the swing path, not the peak of the roof. Sprinkler heads, light fixtures, and unit heaters have wrecked more installs than concrete ever has.

Symmetric or asymmetric, and what that means for tire work

Symmetric columns face each other straight on with the vehicle centered between them, four arms of roughly equal length. Asymmetric rotates the columns about thirty degrees and uses shorter front arms and longer rear arms, which sets the vehicle back so the doors clear the columns. For a shop doing interior work on cars, asymmetric is a gift. For a shop doing wheels and brakes on trucks, the calculus changes.

This shop went symmetric, and a year of tire rotation work has validated it. Symmetric loading keeps a heavy dually balanced front to rear, and the equal arm lengths make pad placement on a boxed frame fast and obvious. When you are spinning four wheels off a service truck, you want the arms where you expect them without thinking. The door-clearance advantage of asymmetric matters far less when half your vehicles are work trucks nobody sits inside during service. That said, we have installed plenty of asymmetric units in general repair shops in the same corridor and they love them. The right answer depends on the vehicle mix, and anyone selling you one configuration for every application is not paying attention. If you are mostly rotating tires, checking brakes, and pulling drums, symmetric on a 2 post car lift is the safer default.

The install: five inches of concrete and a forklift on site

Install day is where quotes turn honest. We cored their slab before scheduling anything and found a consistent five and a half inches of 3,000 psi concrete with no rebar and no post-tension cable. That clears the typical requirement for a 12,000 lb unit, but the two things people skip are cure age and edge distance. Green concrete does not hold an anchor. Neither does an anchor set four inches from a control joint or a slab edge.

The shop had a forklift, which mattered more than they expected. A pair of columns for a machine in this class plus the power unit, arms, and hardware arrives heavy and awkward, and unloading with a forklift turned a two-hour wrestling match into fifteen minutes. If you do not have one, tell us before the truck rolls, because liftgate freight and unloading logistics are cheaper to plan than to improvise. We shot the floor for level, shimmed the columns to spec, torqued anchors, filled and bled the hydraulic system, and ran the safety locks through a full cycle loaded and unloaded. Then we made both techs run it themselves before we left. The single most common cause of a first-year service call on a 2 post car lift is not a defective part, it is somebody who never learned the correct arm placement or never checked that both locks engaged on the same notch.

What the first year of service actually looked like

Twelve months, roughly 1,400 lift cycles by their own rough count, and the total service list was short. We came back at about the six-month mark for a scheduled check: re-torqued the anchor bolts, adjusted the equalization cables a quarter turn each because they had taken their initial stretch, greased the arm pins and the column slide blocks, and topped off the reservoir a few ounces. That is a normal first-year picture. Cable stretch in the first few months is expected behavior, not a defect.

The one unscheduled call was a slow lowering complaint that turned out to be a partially closed shutoff valve somebody had bumped with a creeper. Five minutes. We mention it because a huge percentage of the calls we take on a 2 post car lift resolve to something in that category: air in the lines, a low reservoir, a stuck lock latch, or a vehicle that never got positioned right. Compare that to a call we took from a shop elsewhere with a Challenger two-post where the motor ran, the fluid was full, and nothing leaked but the carriages would not move. That is an internal pump or valve issue, and it needs parts and a technician. Knowing the difference saves you money. If you want the background on that split, our writeups on lift maintenance schedules and troubleshooting a lift that will not raise both cover it in more detail.

What we would tell the next RV shop shopping specs

Start with a weight, not a budget. Put your three heaviest regular vehicles on a scale and write the number down. Then measure your lowest ceiling obstruction, your door width, and your bay depth. Then core or at least sound your slab. Those four numbers eliminate ninety percent of the catalog before you ever look at a price, and they turn a confusing decision into a short list of two or three model numbers. We would rather spend twenty minutes on the phone getting those numbers than sell you the wrong machine and haul it back.

Second, budget for the install and the anchors as part of the purchase, not as a surprise. We talk to plenty of buyers who want to self-install, and for a straightforward baseplate unit on good concrete in a home shop that can be reasonable. In a commercial bay where the equipment is going to see a thousand cycles a year and carry someone’s work truck over a technician’s head, professional install and a documented annual inspection are cheap insurance. Third, buy from someone who stocks parts. Cables, locks, arm restraints, and cylinders are the wear items on any two-post, and a machine sitting dead for three weeks waiting on a seal kit costs more than the part ever did. That is the whole reason we run a parts operation alongside the install side, and it is why our advice on picking a 2 post car lift always includes asking who answers the phone in year five.