Vellum Venom: What is DLO FAIL?

Having previously discussed Day Light Opening (DLO), let’s define DLO FAIL.

And perhaps learn why DLOs sometimes fail?

Simply stated, DLO FAIL is when a design team’s Day Light Opening won’t make production, resulting in replacing glass with plastic “cheater” panels. Therefore, in internet-speak, the DLO truly FAILS.

DLO FAIL usually gives the appearance of a sleeker DLO without resorting to expensive glass. But that’s not the only mission.

The F-150 regular cab (above) implements DLO FAIL to integrate a single door design against multiple body configurations. It wasn’t implemented until the 12th-generation.

The 11th-generation regular cab has glass in the B-pillar, except it’s actually a rear-hinged door. Great idea for truck buyers, right?

Nope.

The designers went too far, making a regular cab more like a pricier super cab. Which goes against the grain of this machine’s mission as the value-packed workhorse, where frills are frowned upon by price-sensitive fleet buyers and thrifty consumers. Or beancounters looking out for the company’s bottom line.

The smarter route was the 10th-generation’s regular cab door, significantly different from the crew cab’s front door. Plenty of precedent, too: Ford turned the four-door 1990 Ford Explorer into the two-door 1993 Ford Ranger with this trick, albeit with more concealing effort. Trucks were predominately two-door before this: quad-door variants were usually limited-production, oddly crafted afterthoughts from the B-pillar back.

But let’s not hammer only on the high volume, multi-cab configuration truck. Even buyers of a fully loaded ($154,000) Tesla Model X get DLO FAIL in the A-pillar as standard equipment.

The company’s concept SUV had a fantastic DLO; too bad even a niche builder gets it wrong sometimes.

So what’s the point? Remember there’s no excuse for DLO FAIL at either end. The Nissan Versa/Tiida or the Ford Fiesta prove that affordable models deserve real DLOs.

And if those are too expensive, perhaps the €5,900 Dacia/Renault Logan shows how not to FAIL on a budget.

Speaking of, what’s the budget to badge engineer the Mercedes GLA 250 into an Infiniti? Doing it with the brand-appropriate “E” shaped quarter window?

Compare the two side-by- side and Infiniti clearly spent some coin so the QX30 sported unique C-pillar skin and rear doors. But there’s no space for their stylized “E” quarter window, so they punted: opting for DLO FAIL.

What a shame, yet it proves there’s many reasons why DLO FAIL makes production. Even if none of them are especially palatable.

[Images: Ford, Tesla, Nissan, and Sajeev Mehta]