Why Toyota keeps losing its tailgates in crashes

The GR Yaris Rally1 has developed a habit of its tailgate falling off in crashes

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With how common an occurrence it’s been of late, Toyota should surely consider homologating its GR Yaris Rally1 without a tailgate.

A facetious claim that may be, but Tom Fowler and his engineering team have certainly (and accidentally) been gathering plenty of data about how the car runs without the tailgate on recent World Rally Championship events.

It’s a look made famous by Esapekka Lappi on Rally Finland back in August when a roll on the penultimate stage cost him not just his Toyota’s tailgate, but its roof too.

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Not to be outdone, Kalle Rovanperä trialed this novel setup two rallies later in Greece. Running wide and clipping a tree was enough to rip the tailgate (and consequently, the rear wing) clean off his Yaris.

Elfyn Evans completed the set in New Zealand. When he, not for the first time in 2022, lost the rear and smacked a bank on the inside of a corner, he was pitched into a roll but luckily landed on his wheels.

While the tailgate gamely clung on initially, it soon parted company with the rest of the car as Evans sped off in a bid to stay in the rally. It was a mission that ultimately proved unsuccessful, as although he made it back to service and the Toyota team had a plan in place to repair the car – even putting two extra mechanics (one from Rovanperä’s car and one from Sébastien Ogier’s) on the job – damage to the rollcage made it impossible for Evans to continue.

A bitter pill indeed given Evans woke up on Saturday morning leading the rally. He’d certainly have rather not joined his team-mates in the club of driving their new-for-2022 Yaris without its tailgate.

But why has this been happening?

The rear-end of the car caving in during a rollover, that’s normal. But seeing a rally car, and particularly a Toyota, without its tailgate isn’t a sight we’ve been used to seeing until 2022.

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“I think it’s coming from [the fact] we have quite a big rear spoiler,” team principal Jari-Matti Latvala explained.

“Of course the attachment of the rear spoiler to the tailgate needs to be strong, and now when the roof is this carbon fiber, it’s not steel like in the old generation car, what happens I think is with these impacts, the carbon fiber breaks.

“Metal will always flex, but carbon doesn’t flex and this is what happens.

“When you have an impact you break the carbon fiber and then there is nothing to hold the tailgate, that’s why it comes out.

“On older cars, the roof was sort of supporting the tailgate.”

Basically, it’s all to do with the spaceframe chassis being used in 2022 for the first time since Group B was outlawed after 1986.

As Latvala mentioned, because each team’s rally car is built around a chassis, the body panels don’t have to be steel as they would be on road cars, so teams have all opted for carbon fiber – a strong yet lightweight material.

But that does mean each panel is less secure than they were during the World Rally Car era – for example, the roof is attached to the car by glue!

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And this is OK because it’s the rollcage, built within the tubular chassis, that protects the occupants in the event of a crash.

“When we went to the new regulations for this year, we amended a lot of things, one of the major things being the chassis,” added Latvala’s counterpart at M-Sport Ford, Richard Millener.

“So we don’t use a production chassis anymore. It’s a completely bespoke chassis, what we call a spaceframe, which means a lot of the body panels are actually made of carbon fiber.

“So all of those panels above the rear of the car are carbon fiber whereas on the old cars it would have had a steel roof and a bit more structure at the back.

“So when you see a roll now, those center panels come off. And it’s what we saw with Elfyn as well with the tailgate, it came off.”

As strange as it may be for Toyota’s GR Yaris to continually be closer to resembling a dune buggy than a rally car, the loss of the tailgate during several of its crashes this year is happening for a very good reason.

Not that anybody within Toyota wants to see it, of course.

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