[vsrikkanth]

The new Landrover Defender has reignited the question, why can't we have the best of both worlds? - the better ride quality, lighter and fuel efficient monocoque with the ladder frame like ruggedness built in for offroading.

I am no expert but basic research always tends towards ladder frame chassis for tough offroading applications while recommending monocoque for urban, highway use. Having seen, such views from BHPians too, I am curious to know if this view changes/be reconsidered given that Rovers have chosen to go the unibody route.

How many of the stalwarts here would still feel that a ladder frame Fortuner / Endeavour is more rugged than a monocoque Defender and why?

[GTO]

Great thread! No doubt that the gap has gotten thinner. That said, body-on-frames have two advantages:

1. Far easier & cheaper to repair in case of damage than monocoques (not something that bothers Land Rovers or its rich customers).

2. Still more robust, abuse-friendly and overload-friendly.

For a hardcore 4x4, body-on-frame remains my preferred choice.

Land Rover's priorities are different, and cost or convenience wouldn't be on top of the list. They are also loaded with electronic wizardry to compensate for any shortcomings. Weight, emission & CAFE norms could also have been motivators for the brand's decision.

[Hayek]

Interesting question. The fact is that even large luxury SUVs with fantastic off road ability like the Mercedes GLS are built on monocoque platforms. The fact is that monocoques can do practically everything you need with far better drivability and ride quality than ladder frames. As GTO mentioned, the key advantage of ladder frames is that they are easy to repair and maintain - and hence customers who care for space and cost, and don’t care for refinement or ride quality love the Fortuners and Endeavors and other such made for EM ladder frame SUVs.

I have mentioned this on other threads - the fact is that people like me who love monocoque SUVs like the X3 or Tiguan would never ever want to own a Fortuner. Have test driven the Fortuner category vehicles thrice - in 2010 (manual Fortuner which had brakes that barely worked), 2012 and 2020 - and these products have just become less attractive compared to the monocoque competition each time I tried them.

Yes, the most expensive SUV in the world, the G Wagon is on a ladder frame. But guess it is the exception that proves the rule.

[S15]

• articulation
• body flex
• body lift (spacer)
• body lift (shackle)
• body lift (add leaf)
• SPOA
• winch mounting
• and many more

How do you go about with these on a defender?


Here are a couple of pics of some purpose built off-roaders. Hard to achieve these with a unibody. (check out this thread here, ESPECIALLY the videos https://www.team-bhp.com/forum/4x4-e...ge-punjab.html (Pics & Videos - JK Tyre Xtreme 4Play 4x4 Competition @ Kikar Lodge, Punjab) )






To my mind at least, the defender is about as capable as a Duster AWD. But a well-specced Wrangler will still leave it in the dust. (actually, no, it will not leave it in the dust, but will pull it out of the dust)
If you're someone who buys an SUV to leave it stock, buy the defender. It will probably take you to leh and back (Some people still buy a 4x4 just to go to Leh, or sandakphu, and are disappointed to find out that all the way upto khardung la is now baby-bottom smooth tarmac.) But then so will a LC Prado. And the Prado will be able to do this. https://img-9gag-fun.9cache.com/phot...E_460svav1.mp4 (mods, how to attach a non-youtube video? )


PS: Also read: https://www.carthrottle.com/post/her...r-off-roaders/

PS #2 : There is also a reason why Toyota is building the next gen LC 300 as a body on frame 4x4. https://gaadiwaadi.com/next-gen-toyo...pied-in-japan/

PS #3 : The real reason LR is a monocoque is because of comfort and luxury.

https://www.youtube.com/watch?v=uNGfa2focZw

[extreme_torque]

Originally Posted by vsrikkanth

The new Landrover Defender has reignited the question, why can't we have the best of both worlds? - the better ride quality, lighter and fuel efficient monocoque with the ladder frame like ruggedness built in for offroading.

I dont think it has reignited any debates. A Jeep Wrangler, Toyota 4Runner or a LandCruiser or a Nissan Patrol customer isnt excited about the new Defender. They are completely different customers. Infact if I was looking at buying a Land Rover Discovery today, I would go for the Defender because they are priced similarly.

Originally Posted by vsrikkanth

I am no expert but basic research always tends towards ladder frame chassis for tough offroading applications while recommending monocoque for urban, highway use. Having seen, such views from BHPians too, I am curious to know if this view changes/be reconsidered given that Rovers have chosen to go the unibody route.

More than the frame is the live axle instead of independent suspension which in turn aids articulation which is paramount for any serious off road vehicle. Defender substitutes mechanicals for complex electronics which are bound to go wrong at some point in time. Land Rover arent known for their reliability.

Ruggedness is also a function of long term reliability and I dont think there has even been a rugged Land Rover except the old Defender.

Originally Posted by vsrikkanth

How many of the stalwarts here would still feel that a ladder frame fortuner/endy is more rugged than a monocoque Defender and why?

A ladder frame anyday for a serious off roader.

[.anshuman]

The biggest problem I see with this car is the “Defender” name. Defender as a stock SUV is brilliantly configured and tuned but lacks the simplicity and cannot be upgraded/customised further. It offers best of both worlds, excellent offroad capability, great ride quality and on road dynamics. As a stock vehicle, it is supremely capable but it lacks mechanical simplicity of the older car, or any other simple Ladder on frame SUV, the reason it cannot be customised and upgraded further with aftermarket parts. Also, everything is so complex, if anything fails, it will cost a bomb to replace, and we all know how reliable modern Landrovers are.

Here is a video I posted few months back. The Defender in this video is standard SE model, without rear active diff.

https://www.youtube.com/watch?v=CWKl...nshumanBishnoi

For regular offroad use or expedition use, a custom prepared simple ladder on frame SUV makes more sense than Defender.

Stock vs Stock SUVs comparison, all with open diffs, Defender is more capable than stock Fortuner and stock Landcruiser 200. But you can upgrade the drivetrain and suspension on the simpler Toyotas to suit your purpose and they will out perform the Defender. Not only the performance, the durability, dependability, ease of maintenance and life will be far superior with the simpler SUVs.

[PrideRed]

Well I don't know how a Defender performs in comparison to its body on frame compatriot, but few areas where body on frame cannot be matched:

1. Abuse friendly or tackling bad/horrible roads, body on frame simply demolishes the bad roads. Only monocoque I can think off is the Duster, not sure how does a GLS or X7 fair. Best part is, things improve as you improve speed in body on frames.
2. When you load the car, monocoque sags and struggle big time. The performance does get impacted heavily and even the powerful SUV's struggle when loaded. Driving dynamics change significantly. Body on frame actually starts performing better as you load, except braking.
3. Defender is an exception, in general, body on frame will perform better offroad, I don't think the monocoques provides as much flexibility/articulation.

If you are driving only on city or 4 lane highway and bad/off roads once in a blue moon, body frame doesnot make much sense, just like one buying a sedan, take it offroad and complain about its poor off road credenitals.

[DirtyDan]

Dare I say it? There have been robust rigid monocoques. There have been weak ladder, easily busting framed vehicles, including some American brands from 30-40 years ago.

99.563% of all aircraft are monocoque and they routinely handle tremendous stress. It's more a question of good engineering and quality control. Not to mention cost effectiveness.

I am not going to get my interior garments in a bunch whether a heavy use off-road vehicle is monocoque or frame. Right now most are frame because of cost effectiveness of the desired result. A time might come when new materials and cost effectiveness favor monocoque.

[Lowflyer23]

Originally Posted by Hayek

Interesting question. The fact is that even large luxury SUVs with fantastic off road ability like the Mercedes GLS are built on monocoque platforms.

I have mentioned this on other threads - the fact is that people like me who love monocoque SUVs like the X3 or Tiguan would never ever want to own a Fortuner. Have test driven the Fortuner category vehicles thrice - in 2010 (manual Fortuner which had brakes that barely worked), 2012 and 2020 - and these products have just become less attractive compared to the monocoque competition each time I tried them.

Yes, the most expensive SUV in the world, the G Wagon is on a ladder frame. But guess it is the exception that proves the rule.

Regarding your first point sir, I think the GLS is not at all a fantastic off-roader. I know a guy who owns the last gen and he is such a bindaas (and rich) person that he used to treat it like a fortuner and the car would get stuck (beached) off-road everytime due to the low ramp over angle because of the long wheelbase. I'm not sure about the current one though.

Yes, monocoques are seriously close to the Ladder-frame SUVs these days in terms of rough road ability and offer far superior on-road dynamics. Also, most of these ladder-frame SUV owners barely take them to rough roads (forget about off-road). This is like wearing a bulletproof vest each time you head out of house just because somebody could maybe attack you.

The most expensive SUV in the world is the Rolls Royce Cullinan which is a monocoque.

[Kosfactor]

First up they are not monocoque, it is Unibody.

In the 1980's they launched the Jeep Cherokee XJ, it had a unibody with an integrated ladder frame underneath welded to the body, XJ was and is considered the best off-road Jeep wagon ever made.

For an off-road vehicle, you need to be able to access the hard points in the chassis to mount roll cage, attach accessories like winch and towing hooks, roof rack etc. When you do break stuff it's easy to repair, the body is optional anyways on a body on frame vehicle.

The new defender is a luxury off-road vehicle like a range rover, it is not going to appeal to the old LR buyer who will now get a landcruiser 70 series instead of this electronic mess that they have created, not to mention ruined the looks as well.

[vsrikkanth]

Thanks everyone for your comments. However, I have a follow-up question on this thread..I may be sounding rudimentary since I am new to the forum and not an expert like many BHPians are, so please correct me if I am wrong... For all those who believe in Toyota's legendary reliability (I too believe, just that I feel its a lot easier/given to achieve the same with legacy tech instead of modern tech) and that the ladder on frame chassis contributes to that reliability, I have this question: Why did Toyota build Sienna as a unibody frame and build Innova as a ladder on frame architecture, when both are vans.. Does it mean, Toyota sacrifices Sienna's reliability for comfort or it is actually possible to build an equally reliable unibody frame....With this question in mind, I am setting aside offroading aspect for the moment and thinking only about the aspects of durability/reliability/repairability...

[haisaikat]

Originally Posted by vsrikkanth

since I am new to the forum

We need to look at the segment and the market each is targetted for. Sienna for the North American market with better roads and Innova for the Asian markets with varied road conditions.

In the US for the car to be successful it needs to safer, spacious and because of higher average speeds the handling needs to improve. So they put TNGA-K platform that is even used for RAV4 / Camry with lower CG (and GC) and FWD since that helps increase cabin space and has hence better handling and safer. Also this is even a more premum offering.

Back here in Asia, the reputation of bad roads dictate bringing abuse friendly platforms which should also be low on maintainance with higher GC. The choice was obvious for Toyota to put in IMV platform which is RWD, high on GC but poor in handling with softer suspensions. In areas where average speeds or speed limits are below 40 kmph even on expressways there is less to complain on handling (or safety as rollovers are lesser due to checked speeds). Also owing to body on frame, design costs are lesser hence lower production cost and more profit while cabbies are still happy saving on reliability.

Look a more spacious premium monocoque FWD offerings in India, Kia Grand Karnival which we thought would be an Innova killer as it can house an Innova inside and still be left with space. Its struggling to make sales owing to the higher price tag and Innova sales are sky rocketing even with regular price increase.

[vsrikkanth]

Originally Posted by haisaikat

We need to look at the segment and the market each is targetted for. Sienna for the North American market with better roads and Innova for the Asian markets with varied road conditions.

In the US for the car to be successful it needs to safer, spacious and because of higher average speeds the handling needs to improve. So they put TNGA-K platform that is even used for RAV4 / Camry with lower CG (and GC) and FWD since that helps increase cabin space and has hence better handling and safer. Also this is even a more premum offering.

Back here in Asia, the reputation of bad roads dictate bringing abuse friendly platforms which should also be low on maintainance with higher GC. The choice was obvious for Toyota to put in IMV platform which is RWD, high on GC but poor in handling with softer suspensions. In areas where average speeds or speed limits are below 40 kmph even on expressways there is less to complain on handling (or safety as rollovers are lesser due to checked speeds). Also owing to body on frame, design costs are lesser hence lower production cost and more profit while cabbies are still happy saving on reliability.

Look a more spacious premium monocoque FWD offerings in India, Kia Grand Karnival which we thought would be an Innova killer as it can house an Innova inside and still be left with space. Its struggling to make sales owing to the higher price tag and Innova sales are sky rocketing even with regular price increase.

I was of the impression that Carnival sits a segment higher than innova and the current sales is decent for the price tag and it's only decent due to the 4 x 4 buyers in the same price range who will never ever offroad...

Disclaimer: I currently own the Carnival.. Except for the boring minivan design, I love the refinement, ride quality, quality of interiors, power, and the infinite practicality it offers...

[GTO]

Mod Note: Let's discuss just offroaders here, not vans. Thanks.

[sridhar-v]

I am fortunate to have a car that is midway between the two types of construction. A monocoque with integrated additional frame. A good 4wd system with low range transfer case. And independent suspension all round.
So it is a bit of a wolf in sheep’s clothing. It can do some serious offroading and still be super comfortable for a 3000 kms highway trip.




http://www.team-bhp.com/forum/4x4-ex...shet-lake.html

http://www.team-bhp.com/forum/4x4-ex...tow-cable.html

Unfortunately such construction is not available in any of the newer models of cars. And that is the reason I will hang on to the Grand Vitara till it completes 20 years.