The 2024-and-newer Polaris RZR XP still retains its factory ball joints with a snap ring, and that clip is the weak point. It deforms or shears under hard landings and the extra leverage of bigger tires, and once it goes the joint has nothing holding it in the A-arm. Keller ball joints remove it entirely — the two-piece housing threads into the arm like a nut and bolt. Hardened 4340 chromoly, greaseable, adjustable and rebuildable.
Todd Keller's original threaded design, now covering the current RZR XP and RZR XP 4 from 2024 onward. On this machine the same joint serves both positions, so you simply choose how many you need.
Key Features
- Two-piece threaded housing eliminates the OEM snap ring
- 4340 hardened chromoly steel housings and studs
- Adjustable and greaseable for correct stud articulation over years of service
- Rebuildable — a worn joint is serviced, not replaced
- One joint fits both upper and lower positions on this platform
- Limited lifetime warranty against manufacturing defects
- Made in USA
Built To Solve: RZR XP Ball Joint Pull-Out and Snap Ring Failure
- Snap ring shearing and letting the joint separate from the A-arm
- Clunking or knocking from the front end over rough ground and whoops
- Play in the wheel when rocked top-to-bottom on a jack
- A new machine already being pushed harder than the factory joint was designed for
- Torn boots admitting water and grit so the joint wears from the inside
- Wanting to fix the known weak point before it strands you rather than after
Best For: New RZR XP Builds Going Straight To Bigger Tires
- 2024-and-newer RZR XP and XP 4 owners adding tires or lift early
- Desert and dune riders loading the front end hard on landings
- Owners who want the upgrade done before the first failure, not after
- XP 4 owners carrying more weight through the front end
- Riders who intend to keep the machine for years and want serviceable joints in it
If your A-arms are machined for oversized housings, look at the Mega Keller line instead — it is stronger but requires that modification.
Specifications
- Material: 4340 hardened chromoly steel, stud and housing
- Design: two-piece threaded housing, no snap ring
- Serviceability: adjustable, greaseable and rebuildable
- A-arm modification: not required
- Positions: one joint serves both upper and lower on this platform
- Warranty: limited lifetime against manufacturing defects, original purchaser
- Manufacturer Part Number: BJK-P-XP1KT#XP (one joint), BJK-P-XP1KT-K-2#XP (two joints), BJK-P-XP1KT-K-4#XP (four joints)
Fitment
- Polaris RZR XP: 2024 onward
- Polaris RZR XP 4: 2024 onward
This is the current-generation RZR XP, not the 2014-2023 RZR XP 1000 — that machine has its own listing. Fitment is not guaranteed on applications not listed above.
FAQ
Is this for the new RZR XP or the older XP 1000?
This listing is the current RZR XP, 2024 and newer. The 2014-2023 RZR XP 1000 uses a different Keller joint and has its own listing, so check your model year before ordering.
Why do RZR XP ball joints pull out of the A-arm?
The factory joint is retained by a snap ring seated in a groove. Hard landings and the extra leverage of bigger tires can deform or shear that ring, and once it goes the joint has nothing holding it. Keller joints thread into the A-arm instead, so there is no clip to fail.
Do I need different joints for the upper and lower positions?
No. On the RZR XP the same Keller joint serves both positions, which is why this product is sold by quantity rather than by upper and lower. Choose one, two, or a set of four for a complete front end.
Do these fit the four-seat RZR XP 4?
Yes. Both the RZR XP and the RZR XP 4 are covered from 2024 onward.
Do Keller ball joints require A-arm modification?
Standard Keller joints do not — they thread into the factory arm as supplied. The Mega version uses an oversized housing and does require machined A-arms, which is the main reason to pick one over the other.
Can these be rebuilt instead of replaced?
Yes. They grease and adjust, and the Keller ball joint rebuild kit for Polaris services them with a new cup, boot and pin when the internals eventually wear.
Why Keller
Todd Keller designed the two-piece threaded ball joint to fix the one part of a stock front end that keeps failing, and SuperATV now builds and backs the line. The design has barely changed because it does not need to: thread the housing in like a nut and bolt, use a chromoly stud, and make the whole assembly serviceable so a worn joint gets rebuilt rather than binned.
Upgrade Your New RZR XP Before The First Failure
On a current machine the usual question is whether to do this now or wait. If bigger tires or a lift are already on the list, the joints are the part that notices first, and the set of four covers a complete front end. Confirm you are on the 2024-or-newer XP rather than an XP 1000, then decide between one, two or all four. The Keller rebuild kit for Polaris services these later rather than replacing them.
Installation Video
Official SuperATV installation walkthrough with Todd Keller: How To Install Keller Ball Joints
