Pair of tapered spring steel bars built for Blue Ox TrackPro weight distribution hitches, rated for an 800 lb tongue weight. They attach to your TrackPro L-brackets to augment the suspension of your tow vehicle and trailer for a smoother, more level ride.
The Blue Ox BXW4040 is a spring bar kit built for TrackPro weight distribution hitches, rated for an 800 lb maximum tongue weight and up to 8,000 lbs gross trailer weight. These tapered spring steel bars augment the suspension of both the trailer and tow vehicle, reducing rear-end sag and giving you a smoother, more controlled ride.
The bars attach to your TrackPro L-brackets (sold separately) and are designed so you can back up without disconnecting. A black powder coat finish helps resist rust and corrosion over the life of the product.
Sized for light-to-medium trailers, up to 8,000 lbs GTW
Tapered spring steel bars reduce rear-end sag and harshness
L-bracket attachment lets you reverse without unhooking bars
Corrosion-resistant finish for long-term durability
Per Blue Ox's official listing, this kit is officially named the TrackPro spring bar kit (not "TruckPro"), designed specifically for Blue Ox TrackPro weight distribution hitches. Blue Ox's product literature does not describe this kit using the term "trunnion style" — TrackPro bars are round, tapered spring steel bars that attach via clamp-on L-brackets, a different design from a bar-and-latch trunnion system. SKU: BXW4040 | Rating: 800 lbs TW | Max GTW: 8,000 lbs
Mounting hardware and L-brackets are not included with this kit — confirm you already have compatible TrackPro L-brackets before ordering. Also confirm your trailer's actual tongue weight to ensure the 800 lb rating is the correct fit for your setup.
General Installation Steps: 1. Remove Old Spring Bars: Detach the current bars from your TrackPro L-brackets 2. Position New Bars: Align the new spring bars with the L-bracket mounts 3. Attach to Brackets: Secure the bars into the clamp-on L-brackets 4. Adjust Tension: Set tension per your TrackPro's installation instructions 5. Test the Ride: Confirm level towing height and smooth operation
In The Box: • Two (2) Spring Bars Not Included: • L-Brackets • Mounting Hardware