How to Inspect Lift Arms for Wear

Knowing how to inspect lift arms for wear is one of the most important habits any shop owner or home garage user can build, because worn arms are one of the leading causes of lift failures we see across Iowa. We’ve walked into shops from Ames to Cedar Rapids where a technician was one bad pin away from dropping a vehicle, and they had no idea because nobody had shown them what to look for. Lift arms take a beating every single day — swinging out, locking under load, and absorbing side stress that most people never think about. This guide walks through exactly what our techs check on every service call, so you can catch problems before they become expensive, or dangerous.

Start With the Pivot Pins and Bushings

Every time you inspect lift arms for wear, the pivot pin and bushing at the base of the arm should be the first stop. This is where the arm rotates out from the column or carriage, and it’s under constant load and friction. Grab the arm and try to rock it up and down and side to side while it’s unloaded. Any noticeable play — more than just a little slop — usually means the bushing has worn thin or the pin itself has worn down to an hourglass shape. On older Rotary lift arms especially, we see pins that have worn oval instead of round after years of heavy use without grease.

If you feel movement, don’t just note it and move on — pull the pin if you can and measure it against a new one from the manufacturer’s spec sheet. A pin that’s lost even an eighth of an inch of diameter can allow enough slop that the arm shifts under a vehicle’s weight, which changes your load geometry unpredictably. We replace pins and bushings as a matched set, never just one or the other, because a new pin in an old worn bushing wears out again within months. This is cheap insurance compared to what happens if a pin shears while a vehicle is in the air.

Check the Load Pads for Cracking and Flattening

The rubber or urethane pads at the end of each arm are the only thing actually touching the vehicle, and they take abuse from every oil drip, every winter’s worth of road salt, and every time someone sets a car down a little too hard. Inspect them for deep cracking, chunks missing, or pads that have compressed and gone flat instead of maintaining their dome shape. A flattened pad no longer seats correctly in the vehicle’s factory lift points, and that means the contact area shrinks right when you need the most stable grip.

We also check the pad’s threaded stud or screw-in adapter for stripped threads or corrosion, since a pad that can spin or wobble on its mount is nearly as bad as no pad at all. In Iowa’s climate, road salt works its way into every pad thread over a winter, and by spring a lot of pads are frozen in place or crumbling from the inside out. Swapping pads is one of the least expensive parts of any lift, so there’s no good reason to keep running degraded ones. If you’re inspecting a used lift before buying it, pad condition tells you a lot about how well the previous owner maintained the whole unit.

Look Closely at the Restraint and Locking Mechanism

Modern lift arms use a mechanical restraint system that keeps the arm from swinging out from under the vehicle once it’s positioned. This is a safety-critical part, and it’s one people forget to inspect because it’s usually tucked underneath the arm where you have to actually crouch down to see it. Check the restraint pawl or latch for bent components, missing springs, or a mechanism that doesn’t fully engage the notches along the arm. If the restraint doesn’t click firmly into place at each detent, the arm can creep out during a lift or while a vehicle is elevated.

We also test that the release lever operates smoothly and that it doesn’t stick in the disengaged position, because a stuck-open restraint defeats the entire safety purpose of the system. On some older Challenger and Rotary arms, we’ve found the restraint spring rusted solid from sitting in a humid shop for years without lubrication. A quick shot of the right lubricant and a manual cycle test during routine maintenance catches this before it becomes a real problem. This is a five-minute check that should happen at every service interval, not just during annual inspections.

Inspect the Arm Structure Itself for Cracks and Bending

Beyond the moving parts, the arm’s steel structure itself needs a visual and physical check. Look along the length of the arm for any bending, especially near the pivot end where stress concentrates most. A bent arm often means it was overloaded at some point, or a vehicle shifted unexpectedly while being lifted. Run your hand along welds and stress points looking for hairline cracks, rust bubbling up through paint (which often signals corrosion working from the inside out), or any place where the metal looks stretched or deformed.

Telescoping arms have an extra wear point where the inner and outer sections slide against each other — check for excessive play in that slide and make sure the extension locks solidly at each length setting. If an arm doesn’t lock securely at full extension, it can retract slightly under load, shifting the vehicle’s balance point without warning. Any structural damage we find on an inspection means that arm gets tagged out immediately, no exceptions, until it’s replaced or repaired by someone qualified to weld on load-bearing lift components.

Compare Both Sides for Uneven Wear

Lift arms rarely wear evenly, and comparing the front and rear, or left and right arms, often reveals problems you’d otherwise miss looking at one arm alone. If one arm’s pivot has noticeably more play than the others, or one set of pads is worn down while the rest look fine, that’s usually a sign the lift has been used with uneven loading habits, or that one arm is doing more work than it should because of an alignment issue elsewhere in the lift.

We recommend keeping a simple written log of arm condition at each service visit — pin play, pad condition, restraint function — so you can spot a trend before it becomes a failure. A shop we work with in central Iowa started logging this after we pointed out one arm was wearing twice as fast as the others, which led them to discover a bent column causing the imbalance. Without that comparison, they would have kept replacing that one arm’s parts every year without ever fixing the real cause.

Know When Wear Crosses Into Replacement Territory

Every part on a lift arm has a service life, and knowing where the line is between

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