If you're hearing that dreaded clicking sound when you're turning or accelerating, you're likely staring down a 2015 polaris sportsman 570 rear axle replacement. It's one of those jobs that every ATV owner eventually faces, especially if you like to play in the deep mud or push your machine through rough, rocky terrain. The 570 is a workhorse, but those CV joints aren't invincible. Once a boot tears and the grease gets replaced by grit and water, it's only a matter of time before the joint starts complaining.
The good news is that you don't need a degree in mechanical engineering to get this fixed. It's a project you can definitely handle in your own garage or driveway with some basic tools and a bit of patience. Plus, doing it yourself saves you a massive chunk of change compared to what a dealership would charge for labor.
How you know your axle is toast
Before you start tearing things apart, it's worth making sure the axle is actually the culprit. Usually, the first sign is a rhythmic clicking or popping noise coming from the rear end. It often gets louder when you're under load or making a turn. If you crawl under the back of your Sportsman and see a torn rubber boot with grease sprayed all over the A-arm and wheel, that's the "smoking gun."
Once that boot is compromised, the clock starts ticking. Even if it isn't clicking yet, a torn boot will let in sand and moisture that acts like sandpaper on the internal bearings. If you catch a tear early enough, you might get away with just replacing the boot, but honestly, by the time most people notice it, the joint is already worn. At that point, a full 2015 polaris sportsman 570 rear axle replacement is the smarter, more reliable move.
What you'll need on your workbench
You won't need anything too exotic for this job, but having everything ready before you start will prevent that frustrated walk to the hardware store mid-way through. You'll definitely want a solid floor jack and some jack stands—never work under a machine supported only by a jack.
For the actual mechanical bits, grab a socket set. You'll need a 27mm (or 1 1/8") socket for the main castle nut on the hub. You'll also need some pliers for the cotter pins, a flat-head screwdriver or a small pry bar, and a rubber mallet. A bit of penetrating oil like PB Blaster or WD-40 is a life-saver if your quad has seen a lot of mud and rust. And don't forget some fresh rags; CV grease is incredibly messy and has a way of getting on everything you touch.
Getting the machine ready
First things first, loosen the lug nuts on the wheel while the quad is still on the ground. It's way easier than trying to fight them while the wheel is spinning in the air. Once they're loose, jack up the rear of the Sportsman and secure it on jack stands. Take the wheel off and set it aside.
Now you'll see the hub and the end of the axle held in by a large nut and a cotter pin. Use your pliers to straighten out that cotter pin and pull it out. If it's rusted and breaks off, don't sweat it too much; you can usually tap it through with a punch or just replace the whole nut if it's really bad, though usually, a little force does the trick. Remove that big 27mm hub nut. If you have an impact wrench, this is where it earns its keep. If not, you might need someone to step on the rear brake to keep the axle from turning while you lean on a breaker bar.
Moving the suspension out of the way
To get the axle out, you need to create some room. You don't necessarily have to take the whole rear suspension apart, which is a relief. Most people find it easiest to just remove the top or bottom bolt from the bearing carrier (the knuckle).
I usually go for the upper A-arm bolt. Once you slide that bolt out, the whole hub assembly can tilt outward. You might have to give it a little wiggle, but eventually, you'll be able to pull the outer end of the axle right out of the hub. Just be careful not to stretch your brake lines too much while the hub is hanging there. I usually use a bungee cord to tie the hub to the rack just to keep the weight off the lines.
The "pop" – pulling the old axle
This is the part that makes most people nervous, but it's actually pretty straightforward. The inner end of the axle is held into the transmission/differential by a small C-clip on the splines. It's designed to "pop" in and out.
Grab the axle bar and give it a firm, quick jerk straight away from the machine. You don't want to pull slowly; you need a bit of momentum to compress that C-clip so it releases. If it's being stubborn—and they often are if they've been in there since 2015—you can use a small pry bar. Gently wedge the bar between the inner CV housing and the transmission case. Be very careful not to mar the aluminum case or damage the seal. A little pressure and a quick "snap" should send the axle sliding right out.
Popping the new one in
Before you slide the new axle into place, take a minute to look at the seal in the transmission. If it's leaking or looks shredded, now is the time to replace it. It's a five-dollar part and you're already right there. Also, smear a little bit of waterproof grease on the splines of your new axle. It'll help it slide in easier and make your life much better the next time you have to do this.
Align the splines of the new axle with the transmission and push it in as far as it will go by hand. Now, you need to seat that C-clip. The best way to do this is to get the axle as straight as possible and give the outer end a solid shove. You should feel and hear a distinct "click" when it seats. Give it a little tug to make sure it's actually locked in. If it slides back out, it's not seated yet.
Putting it all back together
From here, it's just the reverse of what you did earlier. Slide the outer end of the axle back into the hub. Line up your A-arm and slide that long bolt back through. It can be a little fussy to get the holes to line up, so using a screwdriver as an alignment punch can help.
Put the hub nut back on and tighten it down. You want this tight—usually around 80 ft-lbs if you're using a torque wrench. Slide a fresh cotter pin through the hole and bend the ends back so it stays put. Put your wheel back on, snug up the lug nuts, and lower the machine to the ground. Give the lug nuts a final tighten once the weight of the quad is holding the tire still.
A quick test ride
Before you head out on a 50-mile trail ride, do a quick lap around the yard. Listen for any weird noises and make sure everything feels tight. It's also a good idea to check that transmission seal after your first ride to make sure no gear oil is weeping out.
Doing a 2015 polaris sportsman 570 rear axle replacement isn't the most glamorous way to spend a Saturday afternoon, but it's incredibly satisfying. There's nothing quite like the silence of a healthy drivetrain after weeks of listening to an axle complain. Plus, knowing your machine inside and out gives you a lot more confidence when you're miles away from the truck. Now, get back out there and enjoy the ride!