Two Post Lift Arm Restraints and Pads: What Iowa Shops Miss

Two post lift arm restraints and pads are the two most overlooked wear items on any two post hoist, and they’re also the two parts most likely to cause a vehicle to shift or an arm to swing out from under a car mid-lift. We’re Auto Lift Services, based in Ames, Iowa, and we service and stock parts for two post lifts in shops all over the state — from small independent garages to multi-bay dealership service centers. When a technician calls us about a car that felt “loose” on the rack, or an arm that wouldn’t stay locked in position, the restraint mechanism and the rubber pads are almost always the first thing we check. Both are cheap compared to the alternative.

What Arm Restraints Actually Do

Every two post lift with swing arms needs a way to keep those arms from moving once they’re positioned under the vehicle’s lift points. That’s the job of the arm restraint — a mechanical latch, pin, or ratcheting mechanism built into the arm assembly that locks it in place after the technician swings it into position. Without a functioning restraint, an arm can drift or swing free under load, especially during the first few inches of lift when weight distribution shifts. Two post lift arm restraints and pads work together here: the restraint holds the arm’s position, and the pad keeps the contact point from sliding on the vehicle’s frame or pinch weld.

Most manufacturers design their restraints as either a spring-loaded latch that clicks into a toothed rack, or a pin-style lock that the technician sets manually. Either style wears over time. Springs fatigue, latch teeth round off, and pins get bent from repeated use or from techs forcing an arm into position without fully releasing the restraint first. We see this constantly on lifts that run ten or more vehicles a day — the restraint mechanism just doesn’t get the attention the hydraulic system does, even though it’s arguably more critical to safety during that vehicle transition from ground to full height.

Why Pads Matter as Much as the Restraints

The rubber or composite pads on the end of each arm are the only thing between your steel lift arm and the vehicle’s factory lift points. When two post lift arm restraints and pads are both in good shape, the vehicle sits securely with even weight distribution across all four contact points. When pads are cracked, compressed flat, or missing chunks, that contact becomes uneven — one corner of the car can be higher than the others, putting more stress on the opposite arm and increasing the odds of slippage. We’ve pulled cars off lifts in Iowa shops where the pad had worn down to bare metal, and the technician never noticed because the arm still “looked” fine from a distance.

Pads also protect the vehicle. A hardened, worn pad can crack paint, dent rocker panels, or leave permanent marks on frame rails — an expensive mistake for a shop to explain to a customer. Replacement pads are inexpensive relative to a single warranty claim or comeback repair, and swapping them takes minutes with the lift unloaded.

Signs It’s Time to Replace Them

Most shops replace two post lift arm restraints and pads reactively, after something already went wrong. We’d rather see it done on a schedule. Watch for arms that won’t hold their locked position without technician pressure, restraint pins that are visibly bent or won’t seat fully, and ratchet mechanisms that skip teeth instead of clicking cleanly into place. On the pad side, look for compression — a healthy pad should have visible give when you press it; a pad compressed flat has lost its cushioning ability entirely. Cracking, chunking, and a shiny or glazed rubber surface are also red flags.

Any arm that visibly moves once a vehicle is fully lifted needs immediate attention — that’s not a maintenance item anymore, that’s a shop-down situation. We tell every shop we service the same thing: if you wouldn’t trust the arm restraint with your own vehicle up in the air, don’t trust it with a customer’s.

Inspection Should Be Part of Your Routine, Not an Afterthought

A proper inspection of two post lift arm restraints and pads takes less than five minutes per bay but gets skipped constantly because lifts “seem” fine day to day. We recommend checking restraint engagement and pad condition weekly, and doing a more thorough inspection — including hardware torque and visible wear on the latch teeth — monthly or per your state’s inspection interval. For shops that want a documented process, our team put together a two post lift arm restraints inspection checklist that walks through exactly what to look for on each lift style.

Documentation matters more than most shops realize. If OSHA or an insurance auditor ever asks about your lift maintenance program, a dated inspection log showing restraint and pad checks is worth far more than a verbal “we check it sometimes.” It also protects your techs — a documented history shows the shop takes equipment safety seriously.

Matching Replacement Parts to Your Lift Brand

Not every restraint or pad is interchangeable across brands, and this is where a lot of shops waste money buying the wrong part. Rotary, Challenger, BendPak, and Atlas all use different arm geometries, pin diameters, and mounting hardware, and pad shapes vary even between models from the same manufacturer. When you’re sourcing two post lift arm restraints and pads, it’s worth confirming your exact lift model and arm style before ordering — a pad that’s close but not quite right will wear unevenly and fail faster than the correct part.

We keep restraint hardware and pad kits in stock for the major commercial brands we install and service across Iowa, and we can usually match a part from a photo of your lift’s data tag or the arm assembly itself. If you’re also dealing with worn arm bushings or adapter blocks alongside restraint issues, our page on arm restraints and adapters covers how those components interact.

DIY Replacement vs. Calling a Technician

Pad replacement is genuinely a DIY-friendly job for most shops — unbolt the worn pad, bolt on the new one, done. Restraint replacement is a little more involved depending on the lift design; some are a simple bolt-in swap, while others require partial disassembly of the arm to access the mechanism. We always tell customers that if a restraint replacement involves anything beyond basic hand tools, or if you’re unsure whether the new part is seating correctly, it’s worth a quick call rather than guessing.

We also recommend replacing pads in full sets rather than one at a time — mismatched wear between old and new pads can create uneven lift height across the four points, which defeats the purpose of the upgrade. The same logic applies to restraints on lifts where all four arms use identical mechanisms.

Keeping Iowa Shops Running Safely

We’ve built our business around keeping Iowa’s automotive lifts running safely, and two post lift arm restraints and pads are one of the simplest, most affordable ways a shop protects both its technicians and its customers’ vehicles. These aren’t glamorous parts — nobody brags about new arm pads — but they’re the difference between a routine lift cycle and a shop incident report. Whether you run a single-bay independent shop or a ten-lift dealership service department, budgeting for restraint and pad replacement on a regular cycle costs far less than the alternative.

If you’re not sure what condition your restraints and pads are in, or you need parts matched to your specific lift, our team is happy to help you figure it out over the phone or on-site.

Related: two post lift arm restraints · two post lift arm pads