For , General Motors has been boasting the advantages of its steel-bodied Chevrolet Silverado over the aluminum-bodied Ford F-150 in TV ads. Now a new set of “aluminum versus steel” ads is here, purporting to show the F-150's bed cracking under pressure. GM swears the ads aren’t an attack on aluminum itself, but that’s bullshit—again.

And what GM doesn’t realize is that when their trucks inevitably adopt aluminum in some form or fashion too, this campaign is going to come back to haunt them.

The two new clips show how much better the Silverado’s bed is at absorbing sharp impact loads than the F-150's bed. Here’s:

In scientific testing using a wedge-shaped striker weighing 17 pounds (7.7 kilograms), the Silverado sample remained intact up to 90 joules of impact energy. By comparison, the aluminum bed floor exhibited hairline cracks at just 30 joules, and was completely punctured at 40 joules.

As an extreme example of the Silverado’s strength, 55 landscaping blocks weighing a total of approximately 825 pounds (347 kilograms) were dropped into the beds of both trucks from 5 feet above the bed floor.

In 12 out of 12 comparisons shot for video, the Silverado exhibited only scratches and dents that did not affect the utility of the bed. The aluminum Ford F-150’s aluminum bed sustained punctures in every drop, with an average of 4.3 punctures per drop that could reduce the utility of the bed.

And now here are the two clips:

This test is clearly a big deal. A pickup truck’s bed is what makes it, well, a pickup. Many truck buyers’ livelihoods depend on hauling things in their truck beds, so between this and Ford’s other aluminum-related woes (like ), many buyers may be swayed away from the Blue Oval.

Ford says their certified repair centers can fix the 2015 Ford F-150 and its all-new aluminum body…

The Chevy ads are part of an aggressive campaign that TV viewers will see in 30- and 60-second spots during NASCAR, the NHL finals, baseball and more, says .

I have no qualms with Chevy’s test methodology, even if Ford spokesman Mike Levine told us he considers it just a “marketing stunt.” In a conference call about the campaign today, GM told journalists over the phone that it was actually engineers who discovered the difference in bed strength between the trucks, and not the marketing team.

And I think that’s totally fair—a car company has found that they have a competitive advantage in an area, and they want to show customers. There’s no issue there.

The trouble lies with Chevrolet’s repeated claim that the campaign is “not an attack on aluminum.”

That’s the bullshit response I got when I asked Chevy whether they thought this campaign would come back and bite them when they released their own aluminum-intensive truck, which many is going to happen in the near future.

So after a whole ad campaign crapping on Ford’s aluminum F-150, sources say GM’s planning…

They also went on to say:

[Chevy’s] focus is on showing that we have the right material for the right application. We would be remiss if we did not come to market with this message.

Again, that message is totally fair. But that’s not at all the message Chevy is conveying.

Instead of saying “Aluminum is a great material, but not in all applications”—and indeed, it may not be the right material for a truck bed—let’s look at GM’s past ads, which are clearly digs on aluminum itself:

Really? A satirical bit on “Aluminum Man” is not a dig on the material? And then there’s the one with the bears, and if that’s not a criticism of aluminum, I do not know what is.

The newest clips showing the Silverado’s superior truck bed strength is definitely a step in the right direction, but GM could still do a better job at communicating that it’s not attacking aluminum—but instead criticizing certain applications of the material.

After all, given tightening fuel economy standards and America’s current obsession with trucks in the wake of cheap gas, aluminum GM trucks . The question is how GM will use it. As that story put it, executives “have said frequently that they won’t rely too heavily on one material to achieve mass savings.”

But the customers likely won’t see the nuance of that when it happens, and GM is all but certain to tout its use of aluminum (and the benefits therein) just like Ford did. Why would they not?

If GM doesn’t make this message more clear, the company is going to look really dumb when it rolls out its own aluminum pickup—even if that truck continues using steel in certain spots like the bed.