ARK Corporation makes the most widely used jockey wheels in the market. The XO series covers three load ratings — 350 kg (≈770 lb), 500 kg (≈1,100 lb), and 750 kg (≈1,650 lb) — but they look nearly identical. Here's what separates them.
Quick Comparison
| XO350 | XO500 | XO750 | |
|---|---|---|---|
| Load rating | 350 kg (≈770 lb) | 500 kg (≈1,100 lb) | 750 kg (≈1,650 lb) |
| Legs | Standard-duty | Heavier-duty | Heaviest-duty |
| Clamps | Standard sizes | Standard sizes | Larger sizes |
| Best for | Teardrops & mid-size campers | Large campers & hybrids | Heaviest caravans & boat trailers |
XO350: The Standard RV Jockey Wheel
The ARK XO350 is the most commonly fitted ARK wheel on production rigs. Rated to 350 kg (≈770 lb) static load — enough for a fully-loaded mid-size off-road rig, and the weight-saving pick for teardrops and small utility trailers.
Use it for: Black Series HQ12, HQ15, HQ17 (nose weight typically 150–220 kg / ≈330–485 lb loaded). Most rigs with ATM under 3,000 kg (≈6,600 lb).
XO500: For Heavy Rigs and Loaded A-Frames
The ARK XO500 steps up to heavier-duty legs and a 500 kg (≈1,100 lb) rating. The heavier leg and stronger clamp body account for the capacity increase. Mid-size hybrids from other brands — MDC XT-series, OPUS and similar — also typically land here.
Use it for: Black Series HQ19, HQ21 (nose weight can reach 280–320 kg / ≈620–705 lb fully loaded). Any rig where you routinely carry heavy items on the A-frame.
Want the look to match a blacked-out build? The same jack comes as the XO500 Black Edition.
XO750: For the Heaviest Builds
The ARK XO750 carries the highest rating in the range at 750 kg (≈1,650 lb). For most single-axle campers it's more capacity than you need — but if your loaded ball weight is high enough that an XO500 would work near its limit (big tandem-axle caravans, heavily built hybrids, boat trailers), the XO750 restores the safety margin you want when lifting on soft or uneven ground.
Our Recommendation by Rig
| Rig | Nose Weight | Recommended |
|---|---|---|
| HQ12/HQ15/HQ17 | 120–240 kg (≈265–530 lb) | XO350 |
| HQ19/HQ21 | 200–310 kg (≈440–685 lb) | XO500 |
| Heavy tandem caravans / hybrids | 320 kg+ (≈700 lb+) | XO750 |
If in doubt, size up — weigh your trailer fully packed the way you travel, then choose the jack that carries that ball weight with comfortable headroom. A jack working well within its rating lasts longer and works easier than one constantly pushed to its limit.
Shop the full range in the ARK Corporation collection. Not sure of your nose weight? Send us your trailer model and we'll point you to the right jack.