The Ultimate Guide to Lubricating Tadano Slewing Rings and Pinions The slewing ring and pinion sit at the core of every Tadano crane’s rotation system. When they’re in good condition and properly lubricated, the superstructure rotates smoothly with minimal noise. When lubrication slips, problems show up fast — grinding so unds, jerky movement, heat, and premature wear. None of that is cheap to fix. This guide walks through practical lubrication habits technicians rely on in the field. No corporate talk, no fluff — just the steps, checks, and reasoning that help extend the life of these components. Along the way, we’ll touch on sourcing correct Tadano crane parts and how a reliable crane parts supplier fits into long - term maintenance. What the Slewing Ring and Pinion Actually Do The slewing ring is a massive bearing designed to handle axial, radial, and overturning loads. It supports the crane’s upper structure and allows controlled rotation under heavy force. The pinion, mounted on the swing motor, meshes with the slewing ring ge ar teeth to drive that movement. Both components operate under intense pressure. They also sit in an exposed environment where dust, moisture, and grit are always trying to get in. Lubrication is the only thing preventing metal - on - metal contact, which is why small mistakes turn into big f ailures. Preparing the Crane Before You Grease Anything Start by making the crane safe to work on. Park on stable, level ground. Deploy outriggers to stabilize the chassis. Shut down power and follow your lockout steps so you’re not working near live hydraulics or unexpected movement. Before grabbing a grease gun, clean the entire work area. Old grease attracts dirt, and dirt works its way into every gap. Take a few minutes to wipe down the slewing ring housing, the exposed gear teeth, and any fittings. This reduces the risk of pushing debris into the bearing during lubrication. If the crane has recently been working in mud, sand, snow, or saltwater conditions, spend a little extra time on the cleanup. Those environments accelerate contamination more than most operators realize. Inspect Before You Lubricate Many technicians go straight to greasing, but a quick inspection can save a lot of trouble. Start by rotating the superstructure slowly. Listen for grinding or clicking sounds. Notice whether the rotation feels smooth or if it hesitates at certain points. Uneven rotation can indicate worn teeth, flat spots, contamination, or insufficient lubricat ion. Move in close and inspect the slewing ring teeth. Look for shiny patches where grease has been pushed away, or for dark, clumpy grease that suggests dirt ingress. Check the backlash by gently shifting the upper structure back and forth — excessive play isn ’t something grease alone will fix. Seals matter too. A torn, hardened, or out - of - position seal allows dirt in and grease out. If a seal is compromised, plan a replacement. Lubricating through a damaged seal only traps grit in the bearing. A few photos help you document wear patterns over time. Small changes become obvious when you compare them months later. Choosing the Right Grease for Tadano Slewing Systems Grease isn’t interchangeable. Using the wrong type can lead to shearing, breakdown, or washout — all of which expose metal surfaces to direct contact. Tadano specifies the correct grease grade for each model, and that recommendation should always be your first reference. When you don’t have the manual or need an equivalent, go for a heavy - load industrial grease that handles extreme pressure. Lithium complex and calcium sulfonate greases are common choices. Look for EP additives and strong resistance to water washout. If you’re unsure, your crane parts supplier should be able to confirm the right product. A good supplier won’t just sell you grease; they’ll cross - check compatibility with your machine and ensure it aligns with approved Tadano parts and lubrication guideli nes. Don’t mix grease types unless you’re certain they’re compatible. Some thickeners react poorly together and create a paste that doesn’t lubricate properly. How to Apply Grease Correctly Proper lubrication isn’t about pumping as much grease as possible into the system. It’s about getting a consistent film of fresh lubricant across all load - bearing surfaces. Use a clean, dedicated grease gun. Contaminated tools defeat the purpose of lubrica tion. Attach to the grease nipples and pump slowly. As you add grease, rotate the crane a little at a time. This helps distribute the grease along the raceways and gear teeth rather than pooling it in one spot. Watch for fresh grease pushing out of seals or gear mesh areas. That’s your sign that old grease has been displaced. If almost nothing comes out after repeated pumping, you may have a clogged passage. Take your time. Fast greasing tends to trap air pockets and leaves parts of the bearing dry. Avoiding Over - Greasing and Under - Greasing Both extremes cause problems. Under - greasing leaves too little cushioning between metal surfaces. This leads to rapid wear, heat buildup, and noisy rotation. Many early - failure slewing rings fail for this simple reason. Over - greasing creates excess pressure. Seals get forced out of place. Heat increases. In some cases, grease gets pushed into areas where it shouldn’t go. Your aim is steady, periodic lubrication using manufacturer guidelines for quantity and frequency. If you don’t have exact numbers, grease until you see clean material appear, then stop. Smooth rotation after a short cycle is a good sign you’ve reached the right amount. Checking and Maintaining Seals Seals protect the bearing from contamination, but they’re also one of the first components to degrade under harsh conditions. When seals fail, dirt enters and lubrication becomes far less effective. Inspect seal surfaces for cracks, dryness, or displacement. Clean any buildup around the seal lip. A thin film of grease on the outer surface is normal; heavy clumps aren’t and usually mean past over - greasing or contamination. If a seal is damaged, replace it soon. Continuing to grease through a damaged seal simply churns grit inside the bearing and accelerates wear. This is also where you want to rely on verified Tadano parts so sealing strength and fit are correct. Setting a Realistic Lubrication Schedule There’s no universal rule for lubrication frequency because working conditions vary so much. A crane lifting steel beams in a clean yard has very different needs than one working on a coastal pier or a dusty construction site. Base your schedule on: • Operating hours • Jobsite conditions • Load cycles • Manufacturer recommendations Many technicians grease lightly but often. It keeps contaminants flushed out and minimizes the risk of dry spots forming under load. Keep simple notes: date, grease type, amount applied, and any observations. These logs make long - term wear patterns clearer and help you spot developing issues early. Post - Lubrication Checks: What to Watch For After greasing, cycle the slewing ring through several full rotations at slow speed. The movement should feel smoother, not stiffer. If heat rises noticeably around the bearing area, stop and reassess. Look at the discharge grease. Clean, uniform grease is good. Grease that looks gritty, watery, or discolored points to contamination or internal wear. Noise tells a story too. Clicking, popping, or grinding shouldn’t be ignored, even if freshly lubricated. Lubrication can mask symptoms temporarily, but it won’t correct underlying mechanical faults. When Lubrication Isn’t Enough Some issues simply can’t be fixed with grease. Excessive backlash, deep scoring, or chipped teeth suggest mechanical damage. At that point, plan for parts replacement. Work with a reliable crane parts supplier who can identify the correct Tadano crane parts for your model. Slewing rings, pinions, seals, and hardware need precise tolerances. Getting the wrong fit is more than an inconvenience — it can lead to accelerated wear or unsafe operation. Have your crane’s serial number handy when ordering. It ensures you get the right variant, especially for models that have evolved over the years. Final Thoughts Lubricating a Tadano slewing ring and pinion is routine work, but it’s also one of the most important maintenance tasks for crane reliability. A few habits — keeping things clean, choosing the right grease, applying it correctly, inspecting seals, and logg ing your work — go a long way toward extending component life. When parts do need replacing, rely on accurate information and quality Tadano crane parts from a knowledgeable supplier. The slewing system is too critical to gamble on guesswork. Keeping this system healthy keeps the crane rotating smoothly, safely, and predictably — exactly what you need on every job.