BakFlip MX4 Drain Tubes – Official Replacement Drainage System
Our official BakFlip MX4 drain tubes are engineered to channel water away from your truck bed, protecting your cargo and preventing pooling under the tonneau cover. Each drain tube set includes 30 inches of flexible tubing designed to route water from the cover's built-in drainage channels to exit points along your bed rails.
These factory-spec replacement tubes restore full drainage functionality to your MX4 cover. We designed them with UV-resistant materials that withstand extreme temperatures and road chemicals. The flexible construction allows precise routing around bed liner contours and existing hardware without kinking or collapsing.
Whether you're replacing damaged tubes or upgrading an older MX4 installation, our drain tubes ensure reliable water management. The kit includes everything needed for a complete four-corner drainage system, maintaining the weatherproof seal that makes the MX4 our most popular hard folding cover.
Drainage system specifications
Complete Drainage System Components
Our BakFlip MX4 drain tube kit provides everything necessary to maintain proper water evacuation from your tonneau cover. The system includes four pre-measured tube segments that connect your cover’s corner drainage ports to exit points along the bed rails.
Each tube segment routes through dedicated channels we’ve integrated into the MX4 panel framework. The 30-inch total length accommodates trucks with bed lengths from 5.5 to 8 feet, with excess tubing easily trimmed for shorter applications. We include detailed routing diagrams showing optimal placement around wheel wells and bed liner edges.
Installation & Routing Guidelines
Preparing Your Truck Bed
Before installing drain tubes, clean the bed rail area where tubes will route. Remove any debris from inside the tonneau cover’s drainage channels using compressed air. Inspect the corner drain ports on your BakFlip MX4 cover for blockages or damage.
Routing Front Drain Tubes
Front tubes connect from the cover’s cab-side corner ports and route forward along the bed rail toward the cab. Position tubes below the bed rail lip to prevent pinching when the tailgate closes. The driver-side tube typically exits near the cab corner, while the passenger tube routes around the filler neck area.
Material Engineering & Durability
We manufacture these drain tubes from a proprietary polymer blend that maintains flexibility across extreme temperature ranges. The material resists cracking in sub-zero winter conditions while avoiding softening or sagging during summer heat.
The tubing wall thickness balances flexibility for routing with structural integrity to prevent collapse. Internal diameter specifications match the MX4 drainage port outlets precisely, creating a sealed connection without additional clamps. This design eliminates common failure points found in aftermarket drainage solutions.
Essential BakFlip MX4 Maintenance Parts & Accessories
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BakFlip MX4 Drain Tube Installation & Maintenance Questions
The kit includes four drain tube segments totaling 30 inches of tubing. You receive pre-measured tubes for all four corner drainage points on your BakFlip MX4 cover – two front tubes for the cab-side corners and two rear tubes for the tailgate-side corners. Each tube routes from a corner drain port to an exit point along your bed rail.
The retention clip set includes eight clips total, allowing you to secure each tube at two points along its routing path for stable installation.
These drain tubes fit all BakFlip MX4 tonneau covers regardless of your truck make or model. The tubes connect to the MX4 cover's drainage system, not to truck-specific components. As long as you have a BakFlip MX4 cover with integrated corner drain ports, these tubes will fit.
The 30-inch total length accommodates truck beds from 5.5 feet to 8 feet. For shorter bed applications, simply trim excess tubing with a utility knife for a custom fit around your specific bed liner configuration.
Replace your drain tubes if you notice water pooling inside your truck bed after rain, visible cracks or splits in the existing tubes, or if the tubes have become hard and inflexible. Disconnect a tube from the corner port and inspect for internal buildup or collapse.
We also recommend replacement if tubes have pulled away from retention clips repeatedly, or if they're more than five years old. Preventive replacement every 5-7 years ensures optimal drainage performance even if current tubes appear functional.
Most truck owners install these drain tubes themselves in 20-30 minutes using basic hand tools. The installation requires no drilling or permanent modifications to your truck bed. You simply route the tubes from the MX4 corner drain ports along the bed rails and secure them with the included snap-in clips.
Our detailed installation guide shows optimal routing paths for different bed configurations. If you're comfortable performing basic truck bed maintenance, you can handle this installation. The most important step is ensuring tubes don't kink during routing around bed liner contours.
Front drain tubes typically exit just behind the cab corners where water can drain onto the ground without running down the cab or truck body. Position these exits below the bed rail lip to prevent the tailgate from pinching the tubes when closed.
Rear drain tubes should exit just forward of the tailgate hinge area on each side. This placement keeps water away from the bumper and prevents discharge onto following traffic. Avoid routing tubes to exit at the very back of the bed where they're vulnerable to impact damage from loading cargo.
Flush your drain tubes every three months by running water through the MX4 cover's drainage system with a garden hose. Check that water flows freely from all four exit points. Inspect the tubes visually for damage, kinks, or loose retention clips during regular truck washing.
Before winter, ensure tubes drain completely to prevent ice blockages. In spring and fall, clear any accumulated debris from tube exits where leaves and pollen can collect. If you notice reduced flow, disconnect tubes from corner ports and flush individually to remove internal buildup.
Yes, these drain tubes work with both spray-in and drop-in bed liners. The flexible material allows routing around the contoured edges typical of spray-in liners without kinking. The adhesive-backed retention clips attach securely to textured liner surfaces when stake pocket mounting isn't available.
For spray-in liner applications, we recommend routing tubes along the bed rail just below the liner edge where it meets the rail. This protected position prevents liner overspray from blocking tube exits while keeping tubes secure during normal truck use.