why does the headrest manipulate the spine?

Pauly

if i push my head back on the headrest kinda hard, the seat bulges around the mid-back area. what the heck is the purpose for that? has anyone noticed this? cloth seats by the way

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Gun Metallic 2012 370 Z 7AT

Corona370z

I have noticed it but have no Idea why it is. Could be just how the seats are made. Would like to know why but could also live without knowing

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snake1212

Active head restraints, used to reduce whiplash in case of an accident.

Zoren 370

Pelican170

I dont buy that. Ive heard its a flaw in the manufacturing...

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Augustus

No, I think that's exactly what it is.

I've owned Saabs and Volvos that made a big deal about having active head restraints, and those did exactly what the OP is describing. If you pushed back on the headrest, you could move the mechanism inside the seatback and feel it on your upper back.

The idea is to minimize whiplash. Someone rear-ends you, your torso is pushed into the seat like you're accelerating, but obviously much more suddenly & aggressively. Active headrests use the inertia of your upper torso to pivot the headrest forward to help cradle your head in this type of accident.

If the Z has active headrests (anyone?) this is what the OP is feeling.

A couple of quick images illustrate how they work..

Volvo:


Saab:

brucelidat

I actually have a 370z brochure form way back before I got the car that actually calls this feature out in it so it's not an accident.

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Gauge

Neat, I've wondered this since the first day I got my car lol.

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kenchan

yah, when we push our head againt the headrest it feels wierd on our upper backs, but that's just the exast opposite of how it's designed to work. your upper back would push back first during a rear impact which pushes forward the headrest to keep your head from whiplashing.

Lug

You must have the standard options package. With the Executive package, not only do the headrests massage your back, they make sure you get a happy ending too!

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Pauly

i knew they forgot the mechanical arm that does the "old fashioned". im off to the dealer!

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Gun Metallic 2012 370 Z 7AT

bigdog1250

Yep. When I first test-drove the car I was like is there something wrong with the seats? Then I figured out why it was doing that and thought

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FairladyZ

Z® Coupe 370Z® Active Head Restraints Photo | Nissan USA

BAM, no design flaw. Its on purpose.

Augustus

Pelican170

Interesting, but I hate it lol. Everytime I put my head back, i feel like a bar is digging into my back...

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