Do you prefer BOF or unibody for 6th gen?

[GatorGreg]

Please vote for one of the following options:

I insist on body-on-frame (and I WON'T buy 6th gen that's unibody)
I prefer body-on-frame (but I MIGHT buy 6th gen that's unibody)
I prefer unibody (but I MIGHT buy 6th gen that's body-on-frame)
I insist on unibody (and I WON'T buy 6th gen that's body-on-frame)
None of the above

Here's good article to read on the subject:

2013 Body-On-Frame SUVs - Truck Trend

 

[Lester Lugnut]

Will be interesting to see how many here would consider a UNIBODY 4 Runner to be heresy.

 

[GatorGreg]

Will be interesting to see how many here would consider a UNIBODY 4 Runner to be heresy.

Yep - I'm looking forward to seeing the results.

 

[Krayziekid]

I definitely insist that we get a body-on-frame 6th gen, and I will likely buy a late year 5th gen if they decide to go over to unibody.

To me, the 4Runner has never truly been about comfort or luxury or being the absolute perfect road car. No, instead it is an all around beast that handles well on the road, while giving fantastic off-road performance as well. It does so many things right that I think a unibody would ruin.

I can load my car up with my buddies, a whole lotta gear, and a trailer, and it can handle it all like a champ, and that's partially due to BOF. A unibody would have a lower towing and load capacity. If you wanted to go offroad in a unibody (i.e. XJ), it is generally recommended to strengthen the frame rails. The 4Runner was never about doing one thing perfectly, but rather being about to do a plethora of things right.

Seeing as Toyota really seemed to be calling back to their off-road routes with the 5th gens (factory lockers, crawl control, KDSS, TRD Pro options, etc), it would thoroughly surprise me if they threw all of it away for a 6th gen.

But all of that's just, like, my opinion man.... :hiding:

 

[Brique]

Yup. 4runner goes unibody, i predict there will be few members in the 6th gen forum.

 

[who done it]

^^ I think thats a bit drastic, the unibody Jeep XJ did exceptionally well and still is a great offroad vehicle. I really don't think we would lose much if it goes unibody. We just can't do a body lift and fitting tires will become a little bit more difficult, but saftey will probably increase.

I always used to think the BOF thing was a huge deal, but it really hasn't affected my truck build or most of the builds I've seen on this forum.

 

[Gecko]

I prefer BOF but am willing to accept unibody.

I think Jeep has proven that unibody can work in an offroad vehicle, and Toyota has enough know-how to make it happen with suspension settings, lockers, etc.

To be honest, I think we will get a straight rebadge of the Prado before we get something unibody. Toyota isn't going to invest in an all-new unibody architecture for the 4Runner alone. It makes more sense to just rebadge Prado and look for CAFE credits elsewhere.

 

[Xrider237]

i wouldnt buy a unibody 4runner period

i could be wrong but i always thought that one of the reasons cherokees and gc's never could last nearly as long as 4r's is that they werent built as well and being a unibody was one of the main contributors

when my '03 V8 is needing replacement, i'll likely be looking for another 4th gen 4.7- part if the reason is that i want to swap over racks, bumpers and other parts to same generation- the good part is my '03 w 162k still runs and drives like she has fresh legs

 

[cbielat]

Why would one buy a 4Runner if it's a unibody? That's one of the points of its key factors for this truck. If it's a unibody, I wouldn't even consider it a 4Runner.

 

[BlackWorksInc]

Unless it's a tube frame, a unibody just won't be as robust or durable compared to the BoF architecture. Jeep proved that with the JGC, you either end up chasing and welding cracks, swapping bodies, or just saying **** it and going full exo/endo cage. Most every expedition style offroad vehicle tends to be BoF.

 

[Jabberjaw]

I just want her to have a nice body ...

 

[2003-4x4runner]

A few months back I was watching an old YouTube video of a test drive of the new 4Runner 5th gen. The video go's something like this. One guy was driving threw a obstacle course and the other guy from Toyota USA corp was talking about the new 4Runner and a third guy was filming it. The guy from Toyota USA Corp said that Toyota (Japan) wanted to get rid of the BOF and go with the unibody frame. But Toyota USA said "NO" don't get rid of the BOF since it's a tested design and it works great. I'll try to find the video and post it for you guys. I wish Toyota would keep the BOF design, but I wouldn't be surprised if they went with a unibody.

 

[m85476585]

To me it doesn't matter how they build it as long as it's still a 4runner. I want a good rugged lockable 4WD system (none of this mostly-FWD AWD nonsense) and high clearance and good clearance angles. Good suspension and strong 4WD parts that can handle rock crawling are most important. They are perfectly capable of designing a unibody vehicle with that if they want to. I've chosen not to modify my 4runner (for a few years anyway), so if it's harder to lift a unibody vehicle it's not a big deal to me. But I don't see any reason why it would be different except not being able to do a body lift. Finally, it shouldn't look like a jellybean blob like all the other crossover SUVs.

 

[Xrider237]

i have a feeling if toyota goes to a unibody it will go the way of the pathfinder

 

[BlackWorksInc]

To me it doesn't matter how they build it as long as it's still a 4runner. I want a good rugged lockable 4WD system (none of this mostly-FWD AWD nonsense) and high clearance and good clearance angles. Good suspension and strong 4WD parts that can handle rock crawling are most important. They are perfectly capable of designing a unibody vehicle with that if they want to. I've chosen not to modify my 4runner (for a few years anyway), so if it's harder to lift a unibody vehicle it's not a big deal to me. But I don't see any reason why it would be different except not being able to do a body lift. Finally, it shouldn't look like a jellybean blob like all the other crossover SUVs.

You're forgetting one critical thing, the torsional flex when doing rock crawling or technical offroad driving will twist the unibody excessively. A member mentioned in another thread that their JGC does would not close well if they opened them while flexing (like you might to self spot a tricky area) because the unibody was twisting that much. After a while of that you'd see spot welds possibly popping, cracks in the structure and body panels, distortion of the whole vehicle, ect. The main reason BOF is tried and true is because the frame is typically a ladder style that handles repeated twisting very well with a cab that floats on bushings so it isn't subjected to those forces. You could design a unibody to be as robust and they do; they're just usually tube framed rock buggies. Unibody CUVs are about road comfort, trying to design one from the get go as a dedicated offroad platform makes the point of going unibody redundant as it will be too stiff and complex vs. BOF

 

[Lester Lugnut]

Judging from some of the previous comments it would seem that unibody construction is/will be a nail in the coffin for serious backwoods adventure.

 

[gm350reratliff]

Judging from some of the previous comments it would seem that unibody construction is/will be a nail in the coffin for serious backwoods adventure.

It will be but unfortunately, we are either headed there or it will be discontinued.

If the 6th gen were to become a unibody, it would have to be off the charts in terms of power, mpg, style, amenities, and still be able to wheel for me to even possibly consider it.

 

[m85476585]

You're forgetting one critical thing, the torsional flex when doing rock crawling or technical offroad driving will twist the unibody excessively. A member mentioned in another thread that their JGC does would not close well if they opened them while flexing (like you might to self spot a tricky area) because the unibody was twisting that much. After a while of that you'd see spot welds possibly popping, cracks in the structure and body panels, distortion of the whole vehicle, ect. The main reason BOF is tried and true is because the frame is typically a ladder style that handles repeated twisting very well with a cab that floats on bushings so it isn't subjected to those forces. You could design a unibody to be as robust and they do; they're just usually tube framed rock buggies. Unibody CUVs are about road comfort, trying to design one from the get go as a dedicated offroad platform makes the point of going unibody redundant as it will be too stiff and complex vs. BOF

How old of a JGC? Between modern safety standards requiring a lot of high strength steel and the desire for body stiffness in sporty cars, they should be able to figure out how to make it stiff/ strong enough. They have more space for reinforcement in an SUV than in a car, and weight doesn't matter as much. The suspension should be handling most of the flex, not the body or frame.

The Honda Ridgeline (and probably the Pilot) is mostly unibody, but it has a partial frame. It's not great off-road, but the road oriented suspension and relatively weak 4WD system are mostly to blame in my opinion. The 4WD system (VTM-4) is actually really cool in theory, but from what I've read the implementation leaves a lot to be desired. I've never driven one. If they made it with stronger clutches and had much better software for it, it could be a lot better. I don't see why it can't be as good as ATRAC, or better since you can choose which rear wheel you want the power to go to instead of having to divert it with the brakes.

 

[BlackWorksInc]

[MENTION=113611]m85476585[/MENTION]

All unibodies, hell all frames for that matter flex. That's why you have strut tower braces and other bracings for performance vehicles, high-end performance vehicles are designed so the bodies flex in the way they want in turns; that's not exactly the same as 2 wheels in the air with the vehicle flexing heavily on a couple rocks. The flex is a byproduct of natural forces acting on the vehicle. Even while the suspension is taking up a lot of that movement/force. It wasn't a brand new JGC, but it wasn't very old either; forget the exact year. The point is that the bodies will flex, and while the first or even dozen heavy uses may not cause issues, fatigue will eventually set in. Do not confuse crash standards and safety ratings as a means of determining a vehicle frame's strength. It's not as simple as making a strong frame, there's factors like making sections of the vehicle literally destroy themselves and buckle in on themselves to protect the occupants. Crash safety revolves around mitigating and reducing inertial forces more than twisting or flexing you'd see on trails; while there may be some overlap, it's not very much.

 

[T4R2014]

i have a feeling if toyota goes to a unibody it will go the way of the pathfinder

You mean the unibody 1996-2004 Pathfinder? Those were arguably the best generation of Pathfinder, especially with the VQ35 and manual transmission combo. The unibody Jeep XJ is highly regarded, though one of the weaker examples when wheeled hard. Land Rover has also proven that unibody is capable.