Constant-velocity joints -- also known as homokinetic joints -- allow a vehicle to transfer power from the drive shaft to the axle under a wide range of angles and without adding unnecessary friction or movement.
Due to the extreme forces of off-road driving -- and the extreme angles of lift kits and large aftermarket tires -- the CV Joints and boots on Polaris Rangers experience a great deal of stress. Friction, exhaust heat, and the constant pounding by gravity, inertia and the machine’s sprung weight can cause CV boots and joints to heat up, and over time wear down.
Regardless of what brand of axle you have, be it a burly Gorilla Axle or the top-of-the-line Turner Axle, boot damage and CV joint issues are almost inevitable -- especially if you don’t have skid plates and boot guards installed on your rig.
The parts needed to replace a Polaris Ranger boot or CV joint aren’t particularly expensive, but if you take it to a shop or your local dealership to have work done, mechanics will charge well into the triple digits for labor costs alone.
This is because the tire, brakes, and the CV joint itself must all be disassembled in order to get anything done. But don’t let this intimidate you. Replacing boots and axle joints can be done at home, and with minimal effort.
Zooming In On The CV Boot
Some people go out of their way to avoid having to replace their CV boots, going as far as Jerry rigging them with windshield glass sealant to avoid having to replace them. While this temporary fix may suffice for the UTV McGivers out there, it won’t last long and could lead to further damage to your CV joint.
If, for instance, your boot tears and you don’t properly repair or replace it, dust, dirt, and small rocks will get inside, scar the CV balls, and wreak havoc on the interior of the joint. If this happens, don’t even bother repairing or replacing your boot, a new axle is what you’ll need.
Many people experience overheating in their axles -- especially in high-performance Rhino and Turner axles -- which causes the boot to tear, or in some circumstances, melt. If you’re mechanically inclined, you can install a heat-shield to block the exhaust heat and keep it from blasting directly on the boot -- which could be a solution if your rear passenger-side boot is the problem area.
Getting A Handle On the Grease
If you buy a new boot, the package should include both grease and clamps. The included grease packet is measured out to be the exact amount needed, you shouldn’t add any more.
If the kit didn’t come with grease, 880 Crown & Chassis and TRC are the industry leaders in advanced UTV grease. Take care, however, to not overdo it on the grease. If you fill the boot too full, it could squirt out around the wheel as you drive.
Although this excess grease isn’t a problem by itself, spotting grease around the wheel is a tell-tale sign that you didn’t tighten the bands enough or that your boot has torn. So if you put too much grease in there, you won’t know for sure if there’s a problem or not.
As we mentioned earlier, exterior dust and debris can get in the grease and scar the CV bearings and sockets. But internal spalling from defective or broken parts can also get into the grease and find its way through the boot.
For this reason, you should always clean your joint completely and get rid of all the old grease. A handy trick is to soak your CVs in a coffee can filled with unleaded gasoline. This will help clean it and remove all the old grease and debris. Just make sure to blow it dry with an air compressor before assembly.