Testing it on a Polaris RZR

 By the staff of Dirt Wheels

This is what the filter looked like after approximately 120 miles of dusty driving in the desert. It still looks good, and when it does get dirty, it will clean up easily and be ready for another outing.


2019 is the 50th anniversary of Uni Filter. When the company was brand new, foam air filters weren’t that common. Some of the most popular brands had seams that were sewed together, and many of the Uni products were seamless. Few of Uni’s early competitors have survived, but Uni has continued to innovate and improve the product line. Uni has some unique programs for dealers that make stocking the filters a smart plan. All of these strategies have paid off.

This is the Uni filter with the coarse outer filter sleeve removed. We oiled the yellow and the red foam on our machine.


When Uni was a new company, it was developing applications for machines that came stock with a paper, single-use filter media for air filtration. Oddly enough, now that Uni is in the quad and UTV space, many UTVs still use paper-filter elements. To be honest, the paper element in our Polaris RZR 4 Turbo S (or any Polaris) is an amazingly effective unit that has little in common with the paper elements of 50 years ago.

The Polaris filter is large, and it does a great job. When you hear people complaining about the stock filter, they are generally from extremely wet climates. No paper element likes water. Despite the fact that the stock filter cleans the air well, you are not able to effectively clean it.

That means that replacement filters will be a continuing cost for the life of the machine. Uni’s Polaris RZR filter is constructed of two distinct layers of foam with a removable rigid structure inside. Like the stock filter, the inner small-cell foam is bonded to a molded fitting that mates with the stock air intake.

A more open large-cell foam sleeve goes over the main filter. We oiled both layers. The foam is oiled to allow the foam to catch small particles. Unlike the stock filter, the Uni filter can be cleaned, oiled, and reused many times. Our filter came with a Uni Service Kit that included a can of aerosol filter oil and a larger can of aerosol filter cleaner.

This is what comes with the service kit. It has enough cleaner to clean the filter a few times, but only enough filter oil to apply once.



We removed the inner structure and sprayed both sides of both the inner and outer filters with filter oil. The instructions say to use at least 4 ounces of filter oil, and the can holds just over 5 ounces, so you are looking at a single-application can. Uni also offers pour-on oil, and we know that the pour-on bottle with do several filters as large as the Polaris unit our machine takes.

We worked the oil into the foam, then let it sit for a little to get tacky. We blotted the excess with paper towels. After that, we installed the inner screen and went riding. The machine ran great, but it runs great with a fresh stock filter.

The stock filter holds a lot of dirt without starving the engine for air. You can knock off the big chunks, but you cannot clean the filter.

The difference comes after the filter gets soiled. You again remove the inner structure screen, spray both sides with the cleaner and let it sit for 5 or 10 minutes. Simply wash the filter in warm water and soap. Wash and rinse the filter until it is clean with no soap left in the filter.

Blot the filter and allow it to dry completely before you re-oil. The filter installs exactly like the stock filter, but it is secured with a clamp for extra security. Uni makes great air filter systems for all different types of ATVs and UTVs! The Service Kit is $20.95, and the filter is $68.95 for our RZR. Go to www.unifilter.com, or see your dealer or accessory retailer to get your own Uni filter starting at $68.95.


Comments are closed, but trackbacks and pingbacks are open.