How we made this guide: picks and specs come from our catalog and fitment data, owner quotes come from verified reviews and the guide was drafted with AI help, then checked and edited by Trevor Hall.
Tonneau cover drain tubes carry water from the cover's rails or canister down through drain holes near the front of your F-150's bed and out under the truck. BAKFlip hard folding covers such as the MX4 (from $1,199.99) and retractables such as the RetraxPRO MX (from $2,149.99) use them, and fitting the tubes is one step of an easy driveway install that BAK rates at about 30 minutes and Retrax at under 60.
Most leaks come from four things: a kinked tube or one off its spout, a tube end blocked by a liner or mat, a tailgate seal that is not touching and clamps or rails that are not seated.
Quick answer
Most hard folding covers (the BAKFlip MX4 is one) and retractables such as the RetraxPRO MX drain through tubes. Some covers list no tubes and rely on their seals, such as the Extang Solid Fold ALX and the Extang Trifecta 2.0 soft cover. If your cover has tubes, run each one from the front of its rail or the canister into a drain hole in your bed, keep it free of kinks and check that nothing covers the hole. Read your own install sheet first, because the route changes by cover and truck.
Which covers use drain tubes on an F-150
A hard folding cover has side rails that catch water at the panel seams, and a retractable has a canister at the cab end. Tubes send that water out instead of letting it spill into the bed. Here is what the spec sheets on our range say.
| Cover | Type | What the spec sheet says about water | From (F-150) |
|---|---|---|---|
| BAKFlip MX4 | Hard folding | EPDM perimeter seals, dual-action tailgate seal, drain-tube drainage | $1,199.99 |
| BAKFlip MX4 TS | Hard folding | EPDM seals and an integrated water drain system | $1,449.99 |
| RetraxPRO MX | Retractable | Water management system with integrated drain tubes | $2,149.99 |
| RetraxONE MX | Retractable | Water management system with integrated drain tubes; no hinges or joints | $1,549.99 |
| Roll-N-Lock M-Series | Retractable | Integrated channels and drain tubes | $1,699.99 |
| BAK Revolver X4s | Hard roll-up | One-piece vinyl, flush side seals, bulkhead seal (no tubes listed) | $1,399.99 |
| Extang Solid Fold ALX | Hard folding | Triple-fin perimeter seals, hinge cap seals, rubber corners (no tubes listed) | $1,199.99 |
| Extang Trifecta 2.0 | Soft folding | Snap-on triple-fin seals at the rails, bulkhead and tailgate (no tubes listed) | $469.99 |
So do all tonneau covers need drain tubes? No. The last three covers in the table list seals and no drain tubes on their spec sheets. One Solid Fold ALX owner put it plainly:
“I didn’t want to deal with drain hose. Does excellent in wet weather. Keeps cargo dry.”
Extang Solid Fold ALX owner · 4 out of 5 stars
The same ALX has reviews that report leaks at the bulkhead and latches. On a cover without tubes, how well it keeps water out comes down to seal fit. For the full comparison of how each type seals, see are tonneau covers waterproof.
Hard folding with tubes
BAKFlip MX4 Hard Folding Tonneau Cover
From $1,199.99 · Tubes run from the front of each rail through the bed. Easy clamp-on install, no drilling.
Where the tubes go on an F-150
Every tube ends at a drain hole near the front of the bed. The tube starts where water collects: at the front end of each side rail on a hard folding cover, or under the canister behind the cab on a retractable. Retrax's install sheet says some pickups have factory drain holes in both front corners, while others have plastic or rubber plugs that can be drilled out for the tubes. BAK's MX4 sheet has you cut an X in the bed's rubber drain plug and feed the tube through it. Before you start, look in the front corners of your F-150's bed for a hole or a rubber plug, and check that a spray-in liner has not coated it over.
The tubes only drain the cab end. One MX4 TS owner reported that while driving, water in the rails is pushed back to the open rear ends of the channels and into the bed at the tailgate, where the front tubes cannot catch it.
Fit varies by cover. The MX4 fits 2004 to 2026 F-150s, with 8 ft beds from 2015 on. The MX4 TS and Solid Fold ALX start at 2015, and the RetraxONE MX comes in 5'7" and 6'7" beds only. Pick your exact year and bed on the product page. Not sure which bed you have? Measure your truck bed first.
If your bed has Ford's cargo management track, BAK's sheet warns that clamps must not press on bed components, so slide each clamp clear of the track cleats before you tighten it.
Tools and parts
- The drain tubes and hose clips that came in your cover's box (the MX4 kit has 2 tubes and 2 clips)
- A sharp knife or scissors to cut the bed's rubber plug
- Zip ties for slack
- Ratchet and sockets for the clamps (the MX4 uses 9/16 inch and 1/2 inch)
- Soap, water and isopropyl alcohol to clean the bulkhead before the seal goes on
- A helper to set the cover on the rails
- A drill and 1/2 inch bit, only for a retractable on a bed with no drain hole or plug (Retrax's sheet)
Watch the install first
This manufacturer walkthrough shows the MX4 TS going onto a 2024 F-150, including the rail layout, which is where the tubes start.
How to route BAKFlip drain tubes, step by step
These steps follow BAK's Gen 3 MX4 sheet. Other trucks and older kits differ, so the sheet in your box wins.
Step 1: Set the rails and tighten the clamps
Seat each rail flat on the bed cap and clamp it snug plus a half turn. A rail that leans into the bed was tightened too fast or too hard. A leaning rail changes where water collects, so fix it before you touch the tubes.
Step 2: Clean the front wall and fit the bulkhead seal
Clean the top edge of the bulkhead with soap and then alcohol, and let it dry. Stick the seal along the opening and cut it back so 1/8 to 1/4 inch of clear space remains beside each rail. That gap is how water reaches the tubes, so a seal pressed hard against the rail traps water in the corner.
Step 3: Check your drain holes
Find your bed's drain holes before you pick a route. Sprayed-in coatings sometimes close them over. If yours has, open the holes first, because a tube cannot empty into a covered hole.
Step 4: Fit the tube and feed it through the plug
Snap on the hose clip, then slit an X in the rubber plug in the drain hole. Attach the tube at the front of the rail and push it down through the X. Zip-tie any slack. Older kits differ, so check your sheet.
Step 5: Check the tailgate seal and the latches
Unfold the cover and close the tailgate. BAK's check: shut the tailgate, and it should touch the seal's first fin and half of the middle one, while the seal's rear edge rests on top of it. Then confirm every panel latch catches its rail.
Step 6: Re-check the clamps after a week
BAK asks you to re-check every clamp for tightness a week after install.
For the full install, including the tools and the header guides, see how to install a BAKFlip MX4.
Do I need to drill holes for tonneau cover drain tubes?
Usually not for a BAKFlip MX4, where you cut an X in the bed's rubber drain plug. Older BAKFlip kits drill the plastic plug, not the truck. Retrax's sheet allows a 1/2 inch hole in each front corner if your bed has no hole or plug.
Same tubes, plus T-slot rails
BAKFlip MX4 TS Hard Folding Tonneau Cover
From $1,449.99 · The MX4 TS adds rails for racks and has an integrated water drain system.
Drain tubes on a retractable cover
A retractable rolls into a canister at the cab end, and Retrax and Roll-N-Lock both build tubes into that area. The RetraxPRO MX lists a water management system with integrated drain tubes, and the RetraxONE MX lists the same on a one-piece top with no hinges or joints. The Roll-N-Lock M-Series lists integrated channels and drain tubes. Install time on the Retrax covers is under an hour, and the tubes are part of that job. Retrax's sheet has you push each tube fitting into the bottom of the canister until it locks, then run the tubes to the front corners of the bed. If there is no factory hole or plug there, it allows enlarging a hole or drilling a 1/2 inch one, so check what is behind the panel before you drill. One Roll-N-Lock M-Series owner found a drill on the tool list but did not need it, because the drain hole was already there.
In the reviews we checked, 19 of the 200 RetraxPRO MX reviews and 23 of the 199 RetraxONE MX reviews mention drains. These are keyword matches, not complaint rates. The problems that come up:
- Tubes that do not stay seated. One RetraxPRO MX owner, on an F-150 Raptor, wrote that the tubes will not stay in by themselves and that you will need RTV or another way to attach them. Retrax's sheet has you fit the foam washers over the tube fittings, push them into the two holes under the canister until they lock and pull down to check they hold.
- Holes covered by a spray-in liner.
- Hose size on GM trucks. A few RetraxONE MX owners of Chevy and GMC trucks said the supplied hose did not fit their bed's holes.
“I bought the OneMX for my (new to me) 2023 PowerPoint F150. I had the 2013 version of this same Retrax cover on my last truck, and while that cover was great this one is much better. - locking mechanism is more sturdy & reliable - drain tubes from the roll up box are better designed - cover appears to be more waterproof - cover is very sturdy & secure - works well with the automatic tailgate.”
RetraxONE MX owner · 5 out of 5 stars
“The only issue is the spray on bedliner. They cover the 2 holes that are supposed to be used for the drain tubes.”
RetraxPRO MX owner · 5 out of 5 stars
Retractable with integrated tubes
RetraxPRO MX Retractable Tonneau Cover
From $2,149.99 · Holds at any point on the track and has its own water management system.
Retractable with channels and tubes
Roll-N-Lock M-Series Retractable Tonneau Cover
From $1,699.99 · Vinyl over aluminum slats. Check the factory cargo-management track note for your F-150.
If your bed has a liner or a mat
A spray-in liner can coat over the holes your tubes are meant to use, as the Retrax owner above found. With a drop-in plastic liner, BAK's earlier BAKFlip sheet runs the tubes behind or under the liner, and some liners need their corners trimmed so the rail sits flat. Retrax's sheet says that with a plastic liner the drain-tube holes are drilled through the liner only, and it recommends extra holes through the liner floor at its lowest points in front so water can escape. On a 2004 to 2008 F-150, a plastic liner has to be cut in the front corners for the canister.
A rubber bed mat is different, because it sits on the floor. One BAK Revolver X4s owner wrote that water drains under the mat:
“While it is not completely watertight the amount of leakage is minimal through the carwash and with a bed mat in place the water drains under the mat.”
BAK Revolver X4s owner · 5 out of 5 stars
A blocked bed drain hole stops a tube from working just as well as a kinked tube does, so clear the holes whenever you clean the bed.
Folding cover without tubes
Extang Solid Fold ALX Hard Folding Tonneau Cover
From $1,199.99 · Relies on triple-fin and hinge cap seals instead of drain tubes. Rated up to 600 lb.
Soft covers and drain tubes
The soft covers we checked, such as the Extang Trifecta 2.0, list snap-on triple-fin seals at the rails, bulkhead and tailgate and no drain tubes. That does not make them dry in every storm: 17 of the 200 Trifecta 2.0 reviews we checked mention leaks (keyword matches, some of them praise). If water gets in, check that the tarp is tight and the seals at the front corners and tailgate are in place.
The four checks that stop most leaks
- Tube kinked or off its spout. Follow each tube from the rail to the hole. It should hang free and stay connected.
- Tube end blocked. Check for a spray-in liner over the hole, a mat edge pressed over it or a leaf plug.
- Tailgate seal. Close the tailgate and confirm the seal touches it, as in Step 5.
- Clamps or rails not seated. Check that the rail sits flat, the clamps are tight and the cover is square between the rails.
Troubleshooting table
| Symptom | Likely cause | Fix |
|---|---|---|
| Water at the front corners of the bed | Tube off its spout or kinked, or bulkhead seal pressed against the rail | Reseat the tube, remove kinks, trim the seal to leave the 1/8 to 1/4 inch gap |
| Water dripping into the middle of the bed | Water getting past a panel seam, or pooling on a cover that does not sit flat | Check the cover sits square between the rails, then re-seat any leaning rail: loosen the clamps, hold it upright and retighten snug plus a half turn |
| Water near the tailgate | Tailgate seal not touching, a gap between the rail end and the tailgate, or rail water running out the open rear ends of the rails while driving | Do the seal contact check in Step 5. Some owners report a small leak here even on a good install |
| Water backs up in the tube or spills at a front corner | Drain hole blocked by a liner, mat or debris | Clear the hole. On a spray-in liner, open the coated hole. With a plastic liner, Retrax says to drill through the liner only |
| Tubes dry but the bed is wet | Water getting in at a panel seam, the tailgate or the rear ends of the rails | Work through checks 3 and 4: tailgate seal contact, then rails flat and clamps snug |
| Tubes keep popping off | Clip not snapped on, or tube too loose for the hole | Reseat the clip and zip-tie the slack. On a Retrax, push each fitting into the canister until it locks and pull-test it |
| A few drops after a car wash | No cover is sealed against a jet of water | Expect a little. Keep valuables off the front of the bed |
Leak reports exist for every type. Across the reviews we checked, 15 of 200 BAKFlip MX4 reviews, 11 of 79 MX4 TS reviews, 18 of 200 RetraxPRO MX reviews, 16 of 199 RetraxONE MX reviews, 18 of 200 Revolver X4s reviews, 6 of 90 Solid Fold ALX reviews and 4 of 149 Roll-N-Lock M-Series reviews mention leaks. These are keyword matches and some are praise. One MX4 owner was less happy:
“Was hopeful this wouldn't be the case with the integrated drainage system, but it leaks around all the edges & between panels.”
BAKFlip MX4 owner · 2 out of 5 stars
That review blames edges and seams, which tubes cannot fix. Work through checks 3 and 4.
One-piece top, no panel seams
BAK Revolver X4s Hard Roll-Up Tonneau Cover
From $1,399.99 · A single vinyl skin with flush side seals and a bulkhead seal.
Common mistakes
- Skipping the sheet. Tube routes differ by cover, truck and kit age.
- Pressing the bulkhead seal flush against the rail.
- Overtightening a clamp, which tilts the rail.
- Leaving out a tube because it looks fiddly.
Frequently asked questions
Where do tonneau cover drain tubes go?
They run from the front of each side rail, or from the retractable canister, down through the drain holes in your bed. On the MX4 the tube is fitted to the rail and pushed through a cut X in the bed's rubber plug. Retrax's sheet says some trucks have factory drain holes in both front corners and others have plugs you drill out for the tubes.
Do all tonneau covers need drain tubes?
No. Covers that catch water in rails or a canister use tubes, such as the MX4 and the Retrax and Roll-N-Lock retractables. The Extang Solid Fold ALX, Trifecta 2.0 and Revolver X4s list seals and no tubes on our spec sheets.
Why does my MX4 leak?
Start with the four checks: tubes, blocked holes, tailgate seal and clamps. Owners who report MX4 leaks name the edges, the panel seams and water pooling mid-cover.
Can you drive with the drain tubes off?
None of the maker sheets we have say it is fine, and the tubes ship in the kit, so fit them. With the tubes off, the rails have no route for water out of the bed, so it can end up inside it.
Do retractable covers need drain tubes?
Retrax and Roll-N-Lock list tubes or channels on their retractables, so yes, plan to connect them. Compare the options in retractable tonneau covers.
Shop covers that fit your F-150
Compare hard folding tonneau covers or browse all F-150 tonneau covers. For other styles, browse every tonneau cover we carry or read the best hard tonneau covers for the F-150 and the BAKFlip MX4 review.
Find a cover that fits your F-150
Related guides
- Are Tonneau Covers Waterproof? The 6 Most Watertight Covers Compared
- Best Hard Tonneau Covers for the Ford F-150: 8 Picks by Bed Size
- How to Install a BAKFlip MX4 (and Other Hard Folding Covers)
- BAKFlip MX4 Review: Is It Worth the Money?
- BAKFlip MX4 Warranty: What It Covers, How Long and How to Claim