How hard is it to disable or adjust a seat belt load limiter to improve safety?

@shadowfax is right, a fall does not hurt you, it is the sudden stop at the end of the fall. I used to rock climb in my misspent youth (met my wife climbing), the ropes we use have stretch to them much like a bungy strap. Otherwise a small fall and stopping at the end of a non stretching rope would be extremely painful.

Cars are designed the same way. The metal has crumple zones to absorb impact and slow the deceleration. Moving a bit with restriction from the seat belt is part of the equation, to slow down and avoid a sudden stop. One thing the designers are trying to avoid is a coup contrecoup brain injury. Accidents at speeds higher than 45 mph have higher fatality rates, regardless of seat belts, air bags etc. At some point the forces in an accident overcome the best engineering that a car can have. A car could be designed to protect the occupants @ 70mph but it would like the canisters used to transport nuclear rods on a train.


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Didn’t he drive a Cord at one time? Or was that some other superhero?

There’s an awful lot of people figuring a lot of different things that they don’t have the background to speak knowledgeably on. Unless you’re a physicist, a trauma doctor, or a crash reconstruction expert, what you figure is far less meaningful than what the experts figure. And the experts don’t have a problem with load limiters.


Renegade got Flagged for using the word 'Troll ’ . Seems a little over reacting .

Of course maybe it was justified as Snowman seems to be a Automatic Transmission expert - A driving expert about controling skids - An expert on Crash survival equipment in vehicles . Who knows what else he knows about that he will share .


Sorry to break it to you, there is no real for a fictional character.

I had a old girlfriend who said I was her Superman. LOL

So since we are off tangent, superman is at a bar, and says hold my beer, jumps out the window and flies back in again, barfly asks how, superman says it is updrafts, try it, guy jumps out the window and crashes to the ground on to the top of a car (car related reference?), bartender says to another patron he is such an ** when he is drunk.


You’ve clearly never been in a Kirk vs Picard debate. :wink:


Yeah I suppose the Klingons are real, so sorry if you are offended by us getting off base, but open forums it happens, Hoping you have a sense of humor about it @InvisibleSnowman

There was one but I don’t remember who, perhaps The Shadow or The Phantom.
The pre-war Green Hornet had what appeared to be a Lincoln coupe, as they would approach the bad guys hangout he would instruct Kato to turn off the hornet sound.

Oh no, are you going to tell Virginia there is no Santa Claus😁

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Say it ain;t so. :roll_eyes: :roll_eyes:

I think it’s important to remember that if you are injured during a crash, it’s not because your seat belt isn’t engineered well. It’s because one person drove their car into another car, which is inherently dangerous.


Let us suppose, for the sake of argument, that it’s true that modern seat belts with pretensioners, load limiters, etc are worse for a person of normal weight than the previous design which locked on sudden deceleration/bumpy terrain/sharp turns. The solution would then be to buy and drive an older car, which does not have these features.

I would not attempt to modify the seat belts or other safety equipment in a newer car, because then insurance can weasel out of paying for your injuries. If you are driving an older car, which never had those features to begin with, whether it’s your medical payments coverage, or the other driver’s liability coverage, insurance will pay for your injuries.

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Or maybe because I (and 99.9% of everyone) HAVE NO IDEA HOW TO DO THIS! It should never be attempted.


I was not familiar with this change in restraint systems. I tested my 2020 by doing a hard stop at 30 MPH, seatbelts began restraining immediately, but not a hard lockup as older systems.
I, for one, thinks they are fine.

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On the highway yes I think so, but those older cars aren’t strong enough in a driver’s side moderate overlap crash. You just get crushed. You have to get in a full overlap or passenger side overlap to take advantage of the stronger seat belt. The older generation airbags were stronger too instead of being optimized for a 40 MPH IIHS crash where they deflate almost as fast as they inflate, probably to prevent the dummy’s head bouncing back and hitting the B pillar. In the Camry Yaris crash linked below the Camry dummy bottomed out the airbag. Apparently a slight sideways motion caused by hitting another vehicle rather than the IIHS barrier changed things enough for the dummy to hit closer to the side of the airbag and bottom it out. With an older car you lose the better side impact crash protection like side curtain airbags. But after seeing this Yaris Camry crash I wonder how much stronger modern cars are for head on crashes anyway. Maybe side impact is all that has improved.

Maybe I could put a seat belt from a 1997 Camry in a 1998-2001?

Can they weasel out if you don’t wear your seat belt at all?

Most common would be seat belt stitching that is designed to break and lengthen the seat belt during extreme forces, or a torque rod that permanently deforms after a certain about of force pulls the seat belt. That would have to be modified. My concern would be that with the addition of the deformable part in the seat belt mechanism to reduce tension that the other parts were possibly weakened to safe cost.

According to that NHTSA document that I linked to, the 1997 Camry (the first XV20 model) does not have pretensioners or load limiters, but the 1998 does. The IIHS tested a “1997 Toyota Camry LE 4-door” and it got a good rating, apparently without load limiters if the NHTSA document is correct.

Try pulling harder on the seat belt. As you pass 1/2 a ton of force you may find that the seat belt starts to spool out when it wouldn’t on a typical 90s car. The seat belt itself will have a maximum tensile strength that it close to 3 tons – twice the weight of an average car.

They’re designing to optimize results over a wide range of occupant sizes and shapes and crash types. It’s conceivable pretensioning and load release features could be programmed to adapt in real time to occupant weight and seat position, vehicle speed, etc. (maybe some do, who knows?). For anyone inclined to go down rabbit holes, consider the programming of your antilock brake system (I felt I could stop our early '90’s Volvos shorter on a wet road without ALB, but could control steering and stopping far better pointed down hill on ice with ALB, take your pick). Similarly for stability control, steering system, and tire design that must work over a variety of operating conditions, and dozens of other tradeoffs.