This is the strongest ball joint Keller makes for the Polaris Ranger, and it will not fit a stock A-arm. The Mega uses a substantially larger housing and stud than the standard Keller joint — so much larger that the A-arm has to be machined to accept it. On a machine that spends its life loaded, towing, or working a plow, that extra material goes exactly where the failures happen.
Read this before ordering: Mega ball joints require modification of your A-arms. If your arms are stock and you do not intend to have them machined, the standard Keller Ranger joint for your model threads straight in and is the correct part for you.
Key Features
- Oversized housing and stud — significantly more material than the standard Keller joint
- Two-piece threaded design, no OEM snap ring
- 4340 hardened chromoly steel housings and studs
- Adjustable, greaseable and rebuildable
- One joint covers three Ranger platforms — XP 570, XP 900 and early XP 1000
- Requires machined A-arms — not a bolt-in upgrade
- Limited lifetime warranty against manufacturing defects
- Made in USA
Built To Solve: Repeat Ball Joint Failure On A Working Ranger
- Standard-size joints that keep failing on a machine that is always loaded
- Snap ring shearing and letting the joint separate from the A-arm
- Clunking or knocking from the front end on rough ground and washboard
- Play in the wheel when rocked top-to-bottom on a jack
- Plow, winch and heavy-implement work that loads the front end year round
- Owners who have already fitted heavy-duty joints and broken those too
Best For: Hard-Working Rangers With Modified A-Arms
- Ranger owners already running aftermarket or machined arms
- Ranch, farm and commercial machines that never run empty
- Plow rigs carrying weight on the front end through a whole season
- Crew models putting more mass through the same front end
- Anyone having A-arms machined anyway and wanting the strongest joint available while it is apart
If your A-arms are stock, order the standard Keller ball joints for your specific Ranger — the XP 570, XP 900 and XP 1000 each have their own listing.
Specifications
- Material: 4340 hardened chromoly steel, stud and housing
- Design: two-piece threaded housing, no snap ring
- Housing: oversized Mega, larger than the standard Keller joint
- Serviceability: adjustable, greaseable and rebuildable
- A-arm modification: REQUIRED
- Positions: one joint serves both upper and lower on these platforms
- Warranty: limited lifetime against manufacturing defects, original purchaser
- Manufacturer Part Number: BJKM-P-MRG (one joint), BJKM-P-MRG-K-2 (two joints), BJKM-P-MRG-K-4 (four joints)
Fitment
- Polaris Ranger XP 570 (PRO-FIT Cab): 2015-2016
- Polaris Ranger XP 570 Crew (PRO-FIT Cab): 2015-2016
- Polaris Ranger XP 900: 2013-2019
- Polaris Ranger XP 900 Crew: 2014-2019
- Polaris Ranger XP 1000: 2017
- Polaris Ranger XP 1000 Crew: 2017-2018
NOTE: Mega ball joints require modification of your A-arms. Watch the XP 1000 window closely — the two-seat car is 2017 only and the Crew runs to 2018, which matches the early-generation front end. A 2019-or-later XP 1000 is not covered by this part. Fitment is not guaranteed on applications not listed above.
FAQ
What actually has to be modified on the A-arm?
The Mega housing is larger than the bore a factory arm provides, so the arm has to be machined to accept it. This is permanent — an arm cut for a Mega will not go back to a standard joint. Have it done by a shop that has cut arms for these before.
Why does the XP 1000 fitment stop so early?
Polaris changed the Ranger XP 1000 front end after the first years, and this Mega covers the earlier one — 2017 on the two-seat car, 2017-2018 on the Crew. If yours is newer, this is not your part.
Should I buy the Mega or the standard Keller joint?
If your A-arms are stock and staying stock, buy the standard — it threads in as supplied and solves the snap-ring failure just as completely. The Mega is for machines already running machined or aftermarket arms, or ones where the standard joint has failed under load.
Does one Mega joint really cover the XP 570, XP 900 and XP 1000?
Yes, within the years listed. SuperATV supplies one Mega part across those three Ranger platforms.
Do I need different joints for the upper and lower positions?
No. The same Mega joint serves both positions, so choose one, two, or a set of four for a complete front end.
Can these be rebuilt?
Yes. They grease and adjust, and the Keller ball joint rebuild kit for Polaris carries a BJKM-P-MRG option specifically for this joint.
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 Mega is what happens when that design is taken as far as the geometry allows: the same threaded housing and chromoly stud, scaled up past the point a factory A-arm can accept.
Before You Order
Check two things: that your A-arms are machined for Mega housings, and that your model year falls inside the fitment above — the XP 1000 window is narrow. If your arms are stock, order the standard Keller joint for your specific Ranger. If the boots are torn but the joints are sound, the Keller boot replacement kit covers this Mega. If the joints are worn but the housings are good, the BJKM-P-MRG option in the Keller rebuild kit for Polaris services them.
Installation Video
Official SuperATV installation walkthrough with Todd Keller: How To Install Keller Ball Joints
