Do Truck Beds Have Drain Holes?

When manufacturers design and engineer new trucks, they often invest over a billion dollars in the process. You can bet that water flow, both around the vehicle and in the truck bed, are a part of that design. There’s also the aesthetics of the drain points. Who wants to see a big round hole in the corner of the truck bed?

For the last several decades, all pickup truck beds have had drain holes of some kind in the front of the truck bed. Rather than a round hole, these drains are usually small gaps between the floor of the truck bed and the forward wall. They’re designed to not be obvious, but they are certainly there.

  • The lack of drain holes would present several problems. The first that comes to mind for most of us is rust, but it goes far beyond that.
  • Standing water tends to create green algae if left alone long enough. And who wants to de-slime their truck bed before actually using it?
  • We all know how mosquitos love standing water. If the truck was left unused long enough, it could easily become mosquito-infested.
  • With enough water pooled, an unsuspecting driver could have issues with handling of the truck until the water has fully drained out the back.

How To Find Truck Bed Drain Holes

Inside front of truck bed
Look closely at where the bed meets the front bulkhead. There’s a definite gap for drainage.

Just look along the front of the truck bed, close to the corners. You should see a  small gap in the seam where the bed floor meets the front bulkhead. Unloaded pickups are designed to be slightly higher in the rear when empty, so water will naturally run towards the front of the truck. Another way to find the drain holes is to simply pour a cup of water in each front corner, then watch the ground underneath to see where the water hitting the ground is coming from.

How To Open Plugged Drain Holes In A Truck Bed

I’ll start with what you don’t want to do. The drainage points were designed, built and finished to aid in keeping the truck bed dry, and to help prevent rust. Part of the process is being sure the inside edges of the holes are finished, just like the rest of the body. Shoving a wire coathanger or any other abrasive object through the holes could cause a starting point for rust and corrosion.

Here are 3 better options:

  1. Using a good nozzle, hit the area with the garden hose. The water pressure should push the stuck debris through to the ground.
  2. If you have an air compressor, a shot of air could also clear the opening.
  3. Suck blockage out with a shop vac.
Water in tuck bed
This bed has a drop-in liner and no drainage. It’s already collecting slime.

If none of these ideas work, they should have at least cleared the area enough that you can actually see what’s causing the blockage. If you have to go after it, be sure to use something that isn’t going to damage the finish on either side of the bed.

Why Do Truck Beds Have Ridges?

The ridges of a truck bed serve several purposes. Water flow is one of them. Since water always takes the path of least resistance, it will flow to the lower portion of the channels. From there, it will either flow to the drain holes in the front or flow to the back of the bed and drain out under the tailgate. But those ridges do serve other purposes.

  • Ridges create a stronger, less flexible truck bed.
  • Less flexibility means less vibration. This equates to a better driving experience. It also helps prevent nuts, bolts and rivets from vibrating loose.
  • The ridges give moisture a place to go when the bed is full of boxes or other cargo.

As of this writing, Ram trucks are using steel for truck beds. Ford has been making full-sized trucks with aluminum bodies for several years, including the truck bed. Many Chevrolet and GMC truck models are now using forms of carbon fiber for truck beds. But in every case, these beds have front drainage and ridged floors.

Why Aren’t There Drain Holes In The Back Of The Truck Bed?

Truck beds don’t need rear drain holes. Unlike an SUV or other passenger vehicles with a tailgate, a truck tailgate is far from watertight. Water easily flows right out between the bottom of the closed tailgate and the rear edge of the truck bed, just like the engineers designed it to do.

How To Block The Gap Between The Tailgate And The Truck Bed

Okay, we’re off topic a bit here. But what if you’re hauling dirt, sand or some other granulated item that wants to spill through this gap? Or maybe you’re camping in the truck bed, and you just want to keep that draft out.

Pipe insulation is the perfect solution. Just cut it to length. It’s already split so it’s easy to open up a bit and spread over the offending area. Just close the tailgate on it and your leaking or draft issue is solved. Swim noodles also serve the same purpose.

Check Out 15 Features I Absolutely Require On My Next Pickup Truck 

What Are The Rubber Plugs In Truck Beds For?

There’s a lot of speculation in several truck forums about these rubber plugs. They may never serve a purpose in your application, but they are there for a reason… AND THEY AREN’T DRAIN HOLES! 

Rubber plug in truck bed
Plugs like this can be found in several places, depending on the manufacturer.

After spending some time on the phone with Ford, Chevy and Ram professionals at local dealerships, I have no solid answers for most of these mysterious rubber plugs. But I do have several examples of what they actually use them for.

In most cases, these rubber plugs are there to ease the installation of common accessories, The passages could easily be used for routing wiring to a 5th wheel trailer, a slide-in truck camper or some other in-bed accessories. In some instances, they could be there for dealer-installed accessories like Nissan’s Utili-track tie-down system.

Ram makes a dealer-installed bed lighting kit that makes use of these access points. This service rep also said they remove the rubber plugs on the bed floor when they install spray-in bed liners. They do this for drainage.

The plugholes are also used for aftermarket stereo speakers that mount in the box. Rather than completely pull the plug, they cut a hole in it. This gives an added layer of protection against the elements and protects the metal edge from wearing through any wiring. An interesting point, they run the wires out of the cab via rubber plugs in the back wall or in the floor under the carpet.

I’ve also seen one hotshot trucker use the rubber access plugs in the forward wall of the bed to run drainage from their in-bed toolbox. He also ran his dual-whip CB radio coax through these holes, under the truck and into the cab.

The bottom line seems to be that nobody really wants to drill a new hole in a truck, especially when one of these access passages is so convenient.