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Death of the body-on-frame SUV?

118 messages,  Last post on Apr 17, 2012 at 4:51 PM

You are in the Honda Pilot Forum.

What is this discussion about? Chevrolet Tahoe, Honda Pilot, Isuzu Trooper, Ford Expedition, Dodge Durango, Ford Freestyle, Volvo XC90, SUV

Messages Page 5 of 12

#41 of 118 Re: Death of the body-on-frame SUV? [jim314] by sagaliba

Jun 14, 2007 (1:05 pm)

Replying to: jim314 (Jun 14, 2007 8:51 am)
>> But it also seems to me that a unibody would be less stiff than a BOF design outside the passenger compartment
 
Less stiff does not necessarily translate into better crumple zones. On BOF vehicles, crumple zones are strategically placed in front and rear portion of the frame (often appear as tiny waves), so that when enough force is applied (i.e., when vehicle is hit hard), the frame will bend at certain points, and in certain directions. In other words, the way it "crumples" is controlled, and not by relying on the random way the metal may fold.

#42 of 118 Re: Death of the body-on-frame SUV? [sagaliba] by coldcranker

Jun 28, 2008 (2:24 pm)

Replying to: sagaliba (Jun 14, 2007 1:05 pm)
I'm hearing a lot of misunderstanding on this forum. Maybe some actual crash pictures of a BOF will help, compared to a unibody crash.
 
First, note how in these pictures BOF Example -- click on this..., the frame is low, and is still extending out, and has actually penetrated the barrier, representing another car. This is because the frame, with engine/suspension mounts is very stiff and tough, and will skewer the occupants of other, lower vehicles if the BOF hits on a door. Very dangerous. What Ford has done on the above late-model F-150 is to secure the cab to the very tough frame to keep it from collapsing, although the protruding frame doesn't make a great "crumple" zone at all.
 
Now compare that to Unit body crash click here... where the front end is much flatter, with no protruding tough frame to stick out and through the barrier.
 
Conclusions: The frames on pickup trucks and SUVs protrude and can enter a unibody structure. The frames are very stiff and don't collapse much when hitting a unibody vehicle.

#43 of 118 Rather fight than switch! by whiskey62

Feb 21, 2009 (1:54 pm)

MY wife and i were in a 6 car pile up about 2 years ago, our doge was in the front and only took the rear bumper out the chevy taho be hind us and ours were the only ones to drive away and the only ones not having to go to hospital, the other 4 were totaled, we heat with wood and haul it in the durango we camp, and haul frinds around in car pool would not change even if some one gave me something els for free!!

#44 of 118 Re: Rather fight than switch! [whiskey62] by tidester

Feb 22, 2009 (1:14 am)

Replying to: whiskey62 (Feb 21, 2009 1:54 pm)
I'm glad you made it through that ordeal!
 
What will you do if we ever get to the point where no one is making them anymore and your Durango is on its last legs?
 
tidester, host
SUVs and Smart Shopper

#45 of 118 Re: Rather fight than switch! [whiskey62] by bobw3

Feb 22, 2009 (11:12 am)

Replying to: whiskey62 (Feb 21, 2009 1:54 pm)
Your safety probably had more to do with you being in the front of the pileup than anything else.

#46 of 118 Re: Rather fight than switch! [tidester] by whiskey62

Feb 23, 2009 (7:19 pm)

Replying to: tidester (Feb 22, 2009 1:14 am)
Thats not a prob. in this area, i am a shade tree mec. but have rebuilt motors trans. and body work! i have about 30 junk yards that are in driving distance and i take good care of what i have. I do plan on gettin some donors so i have parts . the thing about me being in the front i had to keep my doge out of the back of a jag.

#47 of 118 You Get What You Pay For! by motorhead15

May 28, 2009 (10:51 pm)

The most important safety feature on any vehicle is the driver. The most important thing in a two car accident is the weight of the vehicle. Heavy = Good! After that comes safety features such as airbags, anti-lock brakes etc. Please do not be fooled into thinking a five star front crash rating for a Honda Civic is the same as a five star front crash rating for a Ford Expedition. The Expedition weighs more than twice as much as the Civic and in a head on collision between the two, the person in the Civic is approximately 10 times more likely to die than the person in the Expedition. Oh yes, I know... Some bright person with an econo-box will be quick to jump in and say that an SUV is more likely to roll over than a Honda Civic. Yes this is true. According to government tests, the Civic has a 10% chance of a rollover and an Expedition has a 19%-21% chance of rollover depending on whether it is a 2wd or a 4wd. When was the last time you saw a rollover accident? I live in a huge metroplex and the last time I saw a rollover accident was about two years ago. The average accident that I see everyday is someone running into the back of someone, someone running a light etc. I realize my vehicle (Expedition in case you haven't figured that out yet) has a higher center of gravity but guess what? I drive with that in mind. It's not a sports car and I don't drive it like one. They even have decals on the driver's sun visor warning you that the vehicle has a higher center of gravity. Duh! When shopping for a vehicle, I want the heaviest full frame vehicle I can buy with the most safety features I can get. I weighed my Expedition (2008, 2wd, standard length) when I first got it. The vehicle with a full tank of gas in it, me and no gear scaled at 6,000 pounds. Now I could have got a Ford F-350 pickup that weighs between 7500 and 8500 pounds depending on how you get it equipped but I don't even think you can get side air-bags on one of those. The Expedition has front air-bags, side air-bags, canopy airbags and a host of other safety features because Ford considers it a family vehicle. Do I really need an eight passenger vehicle? Heck no! I'm single with no kids unless you count the dog. She enjoys having her own seat and her own air-conditioner. Sometimes I have me, the dog and the girlfriend in there and let me tell you there is plenty of room. Now on to crumple zones. It is easier to control the rate of crumple zone deformation in a unibody vehicle than a BOF. Now I appreciate the fact that when I hit a unibody car that it is going to soften the blow to me but the Expedition has pre-stressed points or dimples in the forward portion of the frame to buckle/deform at a controlled rate under an extreme impact. There is also about eight feet of crumple zone between me and the front of the Expedition. I don't worry about low speed impacts as much as I do high speed impacts or impacts with heavier vehicles. I am fully aware that if a 70,000 pound semi hits my Expedition, the airbags will do nothing more than provide me with a cushy, comfortable death. At the same rate though I am not going to put myself in something that weighs 2,700 pounds just to save a few dollars in gas. My Expedition when driven very easy gets 14-15 mpg in the city and up to 26 mpg on the freeway at 55 mph. At 12,000 miles a year, a Civic should burn about half as much fuel as the Expedition, which is roughly $700 for the Civic and $1,400 for the Expedition at current gas prices. That means an extra $58 a month it cost me in gas. But wait, what about the environment? Doesn't that big ol' 300 horsepower V8 engine put out more emissions? Probably so but one of my favorite meals is a heapin', hot bowl of spotted-owl soup (YUM YUM!) so that's not a big concern to me. Cars burn so cleanly these days that I really consider this to be a non-issue. I appreciate all of you people out there saving gas in your 30 mpg cars, that will increase my survivability rate in an accident and insure an ample supply of fuel for my vehicle for years to come. I wouldn't worry about the safety aspect of your econo-box though. As long as you don't collide with anything bigger than a butterfly, you'll probably be alright. Well that's about all I have for now. I have some spotted-owl burgers cooking on the grill and it's time to go flip them over. Happy motoring!

#48 of 118 Re: You Get What You Pay For! [motorhead15] by bobw3

Jun 01, 2009 (7:16 am)

Replying to: motorhead15 (May 28, 2009 10:51 pm)
By your logic everyone would be driving big rigs...then your SUV would seem small! Luckily everyone is not selfish and actually thinks more about then just what they see in the mirror. Of cource that's one of the good reasons we have a government...to protect against selfish people who only think of themselves...happy motoring

#49 of 118 Re: You Get What You Pay For! [bobw3] by steve_ HOST

Jun 01, 2009 (7:52 am)

Replying to: bobw3 (Jun 01, 2009 7:16 am)
Heard on the radio this morning that one of the GM plants to be closed this Fall makes full sized pickups. Not SUVs, but I'm assuming most of the pickups were body on frame rigs.
 
GM Closes 14 Manufacturing Plants; Three Service Parts Operations (AutoObserver)

#50 of 118 Re: You Get What You Pay For! [bobw3] by tclarke

Jun 01, 2009 (3:00 pm)

Replying to: bobw3 (Jun 01, 2009 7:16 am)
We are suppose to give up our safety because you choose to purchase something that is inferior in an accident. My wife was in a 72 car pile up during a winter in Michigan and I'm very glad she was driving a Cheverlot Full size truck. Nobody in her vehicle was injured. I cannot say the same for the people who chose less safe vehicles. Agaiin a choice we make.
 
I would not be real quick to let our government decide what we drive. You may not like what they decide to regulate next.

Messages Page 5 of 12

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