Cheaper frame design?

Back when I purchased my 1988 Toyota truck Toyota made a big deal about how their frames were "fully boxed" making them more rigid and better offroad then compared to the Chevy and Ford "open channel" frames which had considerable flex.

The Tacoma ushers in the hybrid frame which is essentially an open-channel frame design.

Now the F150, the Siverado, Jeep Wrangler, and even the little GM Colorado/Canyon are all advertising the benefits of their "fully boxed" frames.

Toyota still uses fully-boxed frames on the Hilux (International Tacoma) and Land Rover models.

What do you all think? Is this an issue or not? Does it really matter. Is there that much of an advantage to a fully-boxed frame, or is the cheaper open-channel frame good enough?

 

Doesn't matter, will rust and look like swiss cheese either way

 

The 2nd Gen tacoma frame has, I believe 3 sections of frame througout. All for a different purpose. Open in the rear for flex and boxed near the engine for rigidity. I wouldn't say fully boxed or not is better or worse, it just depends on what the vehicles primary use is. Fully boxed will be more rigid, as c channel will give flex. Rigid will give a more harsh ride, but pobably better for offroad.

With the crowds crying for car like rides, this is what the engineers come up with.

 

That makes some sense to me moondeath. But consider this... it seems an odd coincidence that Toyota changed from fully boxed frames to this new open frame right about the time they were in hot water over the rust issues with their frames. The recalls were widespread and I just wonder if this wasn't a management decision to switch? As I recall from those times the worst rustong was where water got trapped inside the frame box points. Anyway, they apparently never fixed the frame fust issues
GM and Ford are showing off videos of how rigid the rear end is with one side hanging in air. I know my Toyota creeks and twists quite a lot in those situations.

 

Nissan Frontier has had a fully boxed frame since at least 2005 as well.

 

Boxed is better. Open is lighter and less expensive to manufacture. American consumers couldnt care less. They just want it to ride like a passenger car, have a nice "stance", and get them to and from Burger King.

 

Im assuming of course, but I would say the frame difference is simply for driver comfort. Like you said, the current hilux still has a fully boxed frame. Its more of a work horse compared to the tacoma. Supposedly its much more durable and reliable.

Toyota has given up some reliability and durability in recent years to accomodate the masses of North America. An example would be they went with electronic 4wd and gave up a super reliable manual engagement that had massively fewer problems compared to the electronic engagement.

Look at recent reviews of trucks and the tacoma. Rarely is the concern over long term reliability and vehicle abilities. More so about how quiet and soft the ride is and whether you can touch the radio without reaching, because its extremely inconvienent to reach.

Older reviews were always touting ownership without repairs and abilities of a truck. We've gone very, very soft.

Unfortunately, I think this is pretty much it.

 

I would by far and away rather have a fully boxed frame, I think its all about cost cutting and getting it produced as cheaply as possible.

 

But is the rust problem due to the frame config (full box vs open), sub-quality of material used (more prone to rust?) or poor rust prevention treatment from the factory? I ask because wouldn't a fully boxed frame still rust through if the isn't anything to protect it? Granted it would take longer than an open frame, but it would still rust the same right?

 

Poor rust prevention from the factory. Years ago everything rusted where they used road salt. Now, only a select few special vehicles have significant life shortening problems.

 

Cheaper to make, likely part of it is due to crash ratings and having an area that deforms easily. Rust issue is poor selection of steel type and an absolutely horrid cheap paint with very poor adhesion qualities and applied over poor surface prep. Just not that hard anymore to make a frame much more rust resistant then Toyota does on all their body on frame vehicles. Funny thing is that if you look under the unibody vehicles, you'll notice they hold up to rust much better then the BOF trucks. It doesn't seem to matter much where the trucks are made, even the Japanese made one's like the FJC need special attention paid to the frames to keep rust at bay.