New 2018 Defender to share D5's Aluminium monocoque body.

[TerryO]

Well for those of you who are waiting to find out more about the all new Defender as a option for a more serious off roader and all rounder than the new and what appears at first glance city centric D5 here is some interesting news. The new 2018 Defender will reportedly share the D5's aluminium undercarriage so it won't have a full chassis, nor will it be steel.

New Land Rover Defender - 2018 Land Rover Defender Coming Soon (http://www.roadandtrack.com/new-cars/future-cars/news/a31000/new-land-rover-defender-2018/)

[loanrangie]

I'm not Surprised to hear of a shared platform , it makes economical sense.

[TerryO]

I'm not Surprised to hear of a shared platform , it makes economical sense.

But does it make good engineering sense for what it's intended and stated use is and if serious off roaders don't believe it does measure up then whats the point?

A D4 owner on another forum has mentioned that he recently did a LR factory tour and they had a new model RRS there with a bent sub chassis from being snatched. Suppoesedly the person doing the tour told them that you shouldn't snatch the new aluminium bodied LR's or you risk chassis damage. He recommended that when stuck you need to pull them out slowly without snatching.

If correct then the new aluminium LR's are no longer serious off roaders.

[loanrangie]

Lets face it, it wont be aimed at serious offroaders and the pricetag is likely to reflect that.

[scarry]

Let's hope it doesn't also share wheel size,rear access set up and fuel tank size:angel:

[LandyAndy]

Shame Mitsabishi still owns the rights to the word PAJERO:D:D:D:D:D:D
Andrew

[rick130]

Sounds like it'll be a life style accessory and not a work horse.

Hmm, there's still the G-Wagen. :angel:

[Graeme]

You people obviously haven't read that the new Disco has reinforced steel sub-frames.

[phl]

I'm not sure why everyone is worried about aluminium being used. As long as the engineering is done, there should be no problem.

Brings back memories of when aluminium was first used for bicycles; everyone reckoned "steel was real", and predicted all sorts of dire problem with aluminium; none of which occurred. Of course the same problem when bicycle frames went from aluminium to carbon fibre...

As for bending a chassis (or subframe) with snatching, same things will happen with a steel frame. And if I recall correctly, the current thinking of doing a snatch recovery is no longer a run-up and pedal to the metal, but more taking up the slack, then measured progress. Safer too, as less loading on shackles and straps.

[AndyG]

As long as it comes in Keswick Green and 85 profile.
Um I will almost old enough then to justify an auto. :p

[ramblingboy42]

...that is not an official Land Rover news release so I choose to ignore it.

Land Rover have not , repeat not , at this point in time released any factual information about a new Defender.

Again it is another journalists report .

[Mick_Marsh]

Weight for weight, aluminium is still stronger than steel.

If they make the aluminium chassis/subframes super thin (because the can) you can expect distortion.

An aluminum structure, built to the same standards, weighs roughly 35% to 45% less than the same structure in steel. As a result, if high strength is of the highest priority, the alloy frame can be built to the same structural weight as the steel frame, and then be considerably stronger.

[Tombie]

Very few on here are serious off-roaders.

To claim an alloy frame isn't up to the task is laughable - plenty of Jeep and Pajero out there doing some serious stuff without a problem on monocoque bodies.

As long as the design is solid there won't be a problem.

And perhaps, just perhaps we may need to modify some behaviours - like when synthetic rope became the norm (most 4wd associations Training still hasn't caught up).

Way too much "Chicken Little" syndrome in here at the moment.

[AndyG]

My understanding is it shares an architecture / technology not the same stamping / design of the Disco, chassis. So significant departures are possible,
Do you actually snatch, or apply pressure and pop, I do the latter, two very different techniques.
Only been a LR owner for 2 years, but I believe they respect their origins and the niche the Defender represents.

Somewhat ****ed cheers 😛

[DiscoMick]

Didn't the latest Range Rover cut the weight by about 450 kg from the previous model by going aluminium? Haven't heard any complaints about it going weak.

Sent from my GT-P5210 using AULRO mobile app

[AndyG]

Your rarely need a snatch outside of Harrods :D

[Tombie]

Your rarely need a snatch outside of Harrods :D



Seen plenty there...

[discorevy]

I saw a bloke hanging around there once with mirror shoes on , was that you?:D

[Pickles2]

...that is not an official Land Rover news release so I choose to ignore it.

Land Rover have not , repeat not , at this point in time released any factual information about a new Defender.

Again it is another journalists report .
I hear what you say about "unconfirmed" stuff.....got no time for it myself either, and there's not much being said here anyway, that we haven't read several times before.
However, the quoted source here is Ralf Speth, pretty high up in JLR, who has also said personally, that He's driven the "new" Defender prototype, so at least we know there will be one, unlike the predictions of some on this forum, who said there would not be one.
Like you, I am waiting for some sort of "official" images/specs,....ANYTHING!!
Pickles.

[stealth]

Does this sound like there will be a cab/chassis ute available? Doesn't to me.

[cjc_td5]

Does this sound like there will be a cab/chassis ute available? Doesn't to me.

A rear subframe would deal with that. I would think that to build a full monocoque utility style body would be near impossible anyway as there is not enough "meat" in the rear section to provide the strength required.

Sent from my Nexus 7 using AULRO mobile app

[Pickles2]

Does this sound like there will be a cab/chassis ute available? Doesn't to me.
There has been mention from time to time that there will be THREE different ranges/levels of Defender?
Pickles.

[JDNSW]

A rear subframe would deal with that. I would think that to build a full monocoque utility style body would be near impossible anyway as there is not enough "meat" in the rear section to provide the strength required.

Sent from my Nexus 7 using AULRO mobile app


But, for example, some time back, Holden (and others) were able to produce a trayback and cab/chassis based on a fully monocoque sedan design. It can be done.

John

[ramblingboy42]

interesting....what model was that?

[scarry]

interesting....what model was that?

Definitely wasn't the HG to HZ model run,or the WB.

Maybe a Ford?

[cjc_td5]

Did the commodore tray backs run a full chassis like the older HZ et all or a rear sub frame?

Sent from my Nexus 7 using AULRO mobile app

[stealth]

But, for example, some time back, Holden (and others) were able to produce a trayback and cab/chassis based on a fully monocoque sedan design. It can be done.

John

But could you do that with aluminium? I coudn't imagine it would be strong enough.

[DiscoMick]

There has been mention from time to time that there will be THREE different ranges/levels of Defender?
Pickles.

Pretty sure I've read about there being a single-cab, dual-cab and wagon, but I don't have a link right now.

[Tombie]

But could you do that with aluminium? I coudn't imagine it would be strong enough.



Why? Twice the thickness, 2/3 the weight and just as strong.

[JDNSW]

But could you do that with aluminium? I coudn't imagine it would be strong enough.

Properly designed, an aluminium structure can be just as strong as a steel structure.

The critical property in any practical structure such as a car body is Young's Modulus (for practical materials). This is the factor that is relevant in Euler buckling, which is the failure mode of relatively long narrow structures in compression, such as the top of a chassis rail where the load is between front and rear wheels. Interestingly, for all practical materials (except some exotic ones- e.g carbon fibre), this property is proportional to the specific gravity of the material. This means that everything else being equal, steel and aluminium structures would be the same weight.

But everything else is not equal - a lot of the bits of the body have a minimum thickness requirement to cope with minor damage and corrosion - for the same strength, aluminium is about three times as thick, so a lot of it can be made the thickness needed for strength rather than this minimum thickness. And it is still likely to be stiffer than the steel part, simply because it is still perhaps twice as thick - and the dimensions come into the formula as well.

Consider, for example, the chassis of a Series Landrover. Except for a few reinforcing spots, it is all made of the same thickness metal, this being the minimum feasible thickness to sustain minor damage and corrosion - if it were made of aluminium, it would not have to be three times as thick - probably the top and bottom of the rails maybe twice as thick, sides the same thickness (an engineering calculation to decide), and a lot lighter - but significantly more expensive.

John

[Dervish]

Properly designed, an aluminium structure can be just as strong as a steel structure.

The critical property in any practical structure such as a car body is Young's Modulus (for practical materials). This is the factor that is relevant in Euler buckling, which is the failure mode of relatively long narrow structures in compression, such as the top of a chassis rail where the load is between front and rear wheels. Interestingly, for all practical materials (except some exotic ones- e.g carbon fibre), this property is proportional to the specific gravity of the material. This means that everything else being equal, steel and aluminium structures would be the same weight.

But everything else is not equal - a lot of the bits of the body have a minimum thickness requirement to cope with minor damage and corrosion - for the same strength, aluminium is about three times as thick, so a lot of it can be made the thickness needed for strength rather than this minimum thickness. And it is still likely to be stiffer than the steel part, simply because it is still perhaps twice as thick - and the dimensions come into the formula as well.

Consider, for example, the chassis of a Series Landrover. Except for a few reinforcing spots, it is all made of the same thickness metal, this being the minimum feasible thickness to sustain minor damage and corrosion - if it were made of aluminium, it would not have to be three times as thick - probably the top and bottom of the rails maybe twice as thick, sides the same thickness (an engineering calculation to decide), and a lot lighter - but significantly more expensive.

John

That's a good point, but my understanding of why steel has always been used for chassis is that it has a fatigue limit. I understand that Land Rover would've done their homework on this and designed for acceptable cycle life, but unlike steel there will be a cycle life. I'd like to believe the aluminium chassis is a step made purely in the belief that the vehicle will be better for having it, but I can't shake the feeling it is to get low emissions/fuel consumption/0-100km/h times and to hell with longevity.

Will an aluminium chassis bent if you hit it, or will it gouge - causing stress concentration points and dramatically reducing the cycle life? Can an aluminium chassis be repaired?

[JDNSW]

That's a good point, but my understanding of why steel has always been used for chassis is that it has a fatigue limit. I understand that Land Rover would've done their homework on this and designed for acceptable cycle life, but unlike steel there will be a cycle life. I'd like to believe the aluminium chassis is a step made purely in the belief that the vehicle will be better for having it, but I can't shake the feeling it is to get low emissions/fuel consumption/0-100km/h times and to hell with longevity.

Will an aluminium chassis bent if you hit it, or will it gouge - causing stress concentration points and dramatically reducing the cycle life? Can an aluminium chassis be repaired?

Steel has always been used for chassis because it is the most cost effective. Actually, steel has not always been the material of choice - in the early days of motoring, wood was a common chassis material, and in a few instances continued possibly as late as the 1970s - for example in some model Morgan sports cars.

Aluminium does not necessarily have a fatigue life (e.g. the alloy used on the DC-3), and steel does not necessarily not have one. It all depends on the alloy used and the structural design.

An aluminium chassis will bend if you hit it hard enough, same as a steel one - and will undoubtedly crack like the steel 130 ones do if overloaded with a poorly engineered tray. There is nothing to suggest that an aluminium chassis would be harder to repair than steel, except for slightly greater demands on welding equipment and skill. And the corrosion problem should be markedly less, meaning fewer repairs are required. It will gouge to a greater extent than does steel, but the effects of this can be neutralised by proper design.

John

[cripesamighty]

Good point John. Fatigue-wise, the DC-3 was practically indestructible!

[frantic]

Just a quick thought, i think it was JLR's former owner or maybe toymota who had a "flashy" alloy suspension system on an overseas model that was adapted locally using steel to a previous model.
Lets say JLR do the same with the defender(i mean production is rumored for Uzbekistan isn't it?:D ), certain large bits like body are still aluminium, but some of the chassis or suspension is made from steel where its cheaper, kind of like ford did with the latest F1-350 series which have aluminium bodies!
Have a look at Section 3: 2017 Ford F-150 Full-Size Pickup Truck | Built Ford Tough | Ford.com (http://www.ford.com/trucks/f150/)
They state 78% of the chassis is steel with a aluminium body. Hmmm, Whats the other 22% ???

[DiscoMick]

Slovakia?

Sent from my SM-G900I using AULRO mobile app

[JDNSW]

Good point John. Fatigue-wise, the DC-3 was practically indestructible!

Purely by accident - they knew little about metal fatigue in 1936 (or 1934 if it is the same alloy as the DC-2, which it probably is).

And, if my memory serves correctly, metal fatigue of steel structural members was behind an Australian Stinson? it had been converted from three to two airliner losing a wing in about 1940 (it had been converted from three to two more powerful engines because of wartime parts shortages).

John

[akelly]

If they do an good quality auto and put in cruise with 4 wheel discs and coils I might be able to drag myself out of the Amarok, back to LR. In fact, probably not even then considering my lease is up mid-17 I'll probably just replace the Rok with another and watch to see what happens with the new Defender, maybe get the SII in 2020... :D

[Summiitt]

I just had a look over the new G-wagen commercial fitted up as a light unit for fire fighting..very impressive bit of kit, I personally think that with the roll out of the government units, it will be only a matter of time before they are available to the public.. Landrover will need to hit the commercial market hard with a brilliant vehicle if in fact they are doing a cab chassis option. The only thing that should be carried over to the new defenders is it's off road load carrying capacity.

[JDNSW]

Perhaps worth mentioning that aluminium chassis are not new. Designs by Gregoire using these were in production as early as 1938 (Hotchkiss) and post war by Panhard and abortively by Hartnett in Australia. (Panhard nearly went broke building in Aluminium and changed to mostly steel in the fifties!)

So alloy chassis are not really new.

John

[frantic]

Here's the new Merc dual cab designed to take on the amarok and top line Japanese utes( all Thai built) due in showrooms about 6-12 months before defender.
https://pickup.mercedes-benz.com/content/mb-pickup/en/highlights.html

[Slunnie]

Very few on here are serious off-roaders.

To claim an alloy frame isn't up to the task is laughable - plenty of Jeep and Pajero out there doing some serious stuff without a problem on monocoque bodies.

As long as the design is solid there won't be a problem.

And perhaps, just perhaps we may need to modify some behaviours - like when synthetic rope became the norm (most 4wd associations Training still hasn't caught up).

Way too much "Chicken Little" syndrome in here at the moment.
Yep, how many here have had a factory alloy wheel break through normal use (ie actually with air in it). Probably none.

[ramblingboy42]

Yep, how many here have had a factory alloy wheel break through normal use (ie actually with air in it). Probably none.

you are saying "factory" alloy wheel...

do you mean OEM?

I've had 2 leading brand supposed off-road alloy wheels break

[JDNSW]

Just for comparison, talking of wheels, a few years back my son had all five steel wheels fail due to fatigue cracking (not a Landrover, but a well known brand of family car from Korea).

And many years ago my wife had a flat on the County that turned out to be the result of a crack a foot long along the bottom of the well on a standard steel wheel.

John

[LandyAndy]

Here's the new Merc dual cab designed to take on the amarok and top line Japanese utes( all Thai built) due in showrooms about 6-12 months before defender.
https://pickup.mercedes-benz.com/content/mb-pickup/en/highlights.html

Its a Nissan Navara tarted up.
The 5 link rear coil suspension is already available on the upper end Navaras.I wonder if they have rear discs??? All the japer dual cabs run rear drums for some stupid idea.
You should try and stop a Holden Colarado with a full 400lt diesel tank on the back on a gravel or muddy road.The ABS is abysmal,they run seperate channels for the front discs and 1 channel for the rear drums,the fronts do all the work,ABS cuts in with little pedal effort,BLOODY DANGEROUS!!!!
Andrew

[JDNSW]

..... All the japer dual cabs run rear drums for some stupid idea.
......

Rear drums have persisted mainly because they make it a lot easier to fit a handbrake, a problem that is solved differently with the Defender.

Although interestingly, the first family car to have discs (1955 Citroen) had drum rear brakes - and the handbrake operated on the inboard front discs! (Discs were very new at the time, and drums were considered adequate at the rear considering how little weight was on the rear wheels - front wheel drive and the rear wheels almost touch the bumper.)

John

[Slunnie]

you are saying "factory" alloy wheel...

do you mean OEM?

I've had 2 leading brand supposed off-road alloy wheels break

Yep, factory meaning it has a LandRover part number.

The engineering in factory wheels are better than I've seen in any other non-race wheel, theyre not going to break. LR know how to engineer and work in Aluminium with these things and for offroading, the chassis will be fine.

[AndyG]

We live in interesting times, if they get it right, will it be the knock out punch for the Toyota troopie

[Pickles2]

We live in interesting times, if they get it right, will it be the knock out punch for the Toyota troopie
Well, I guess the Car business is all about sales, & if ya look at JLR's sales records for ALL of their recently introduced models, ya'd have to say, they "got it right".
So, in terms of the "New" Defender, I'm VERY confident that they will get it right, particularly in terms of sales & acceptance.
Now whether that vehicle will be accepted by "traditional" Defender owners, who at last count were purchasing only 15,000 per year world wide, is quite another matter. I suggest that whilst JLR do care about us, & our thoughts on Defender, they will (they will have to be) be looking to a far wider market than that.
Like others, I know NOTHING about the "New" Defender.
"Troopie"?.....for sure, but jeez there's massive competition in the market isn't there, from all sorts of brands & vehicles. Where will Defender fit in?....I wouldn't have a clue!!
Pickles.

[AndyG]

Troopies are minimal in Oz, both due to safety and the alternative choices, but when you look at the global market for NGO, U.N , Military, and Mining/Agriculture for a 5 * safety solid as brick **** house solution there is a huge market held by antiquated Patrols and Troopies.

Where i am we have 150 troopies in 3rd world poverty pack, they get a pounding and get maintained by barely competent mechanics. And survive. Apart from everything else lets hope they remember the KISS principal.

A modern safe, rugged, functional vehicle should walk all over that market.

[Avion8]

Troopies are minimal in Oz, both due to safety and the alternative choices, but when you look at the global market for NGO, U.N , Military, and Mining/Agriculture for a 5 * safety solid as brick **** house solution there is a huge market held by antiquated Patrols and Troopies.

Where i am we have 150 troopies in 3rd world poverty pack, they get a pounding and get maintained by barely competent mechanics. And survive. Apart from everything else lets hope they remember the KISS principal.

A modern safe, rugged, functional vehicle should walk all over that market.

Toyota's latest MY2017 70 Series pick up now has airbags & with other modifications achieved a 5 star ANCAP, but it is only the pick up, the troopie & wagon for some reason did not achieve the 5 star rating. I'm sure Land Rover could have done similar with the Defender! They will have lost a lot of business in the 2 year gap until the new Defender is available.

[jon3950]

I suspect they did the minimum required to achieve a 5 star rating on their minespec ute.

Cheers,
Jon

[DiscoMick]

I wonder if they were not able to make the structure of the vehicle crush in the required way to absorb the impact forces and protect the occupants.

[Pickles2]

Toyota's latest MY2017 70 Series pick up now has airbags & with other modifications achieved a 5 star ANCAP, but it is only the pick up, the troopie & wagon for some reason did not achieve the 5 star rating. I'm sure Land Rover could have done similar with the Defender! They will have lost a lot of business in the 2 year gap until the new Defender is available.
Gotta disagree with you on that one.
Ya gotta remember that Defender was only achieving 15,000 sales P.A., sometimes less, before the last "rush". To continue, Defender had to have airbags,..VERY costly, maybe impossible to engineer within Defenders frame, & even if JLR did that, how would that increase sales,...in addition, engines had to go to Euro 6, and even if they did that, it would not change Defender, it would not increase the "appeal"/ marketability of Defender, which had had its day, except for,......Defender "Tragics" like us, and "We" are not the market.
There are a whole range of aspects of why, what we like, has been passed by, by the market, which was simply, not interested in buying Defender in it's present configuration.
IMHO of course, Pickles.

[ramblingboy42]

Toyota have just achieved their Ancap 5 rating on all their 70 series "tojos".

Land Rover will never capture the Australian market that Toyota will now be able to tap into.....specifically mining.

[Slunnie]

Its a Nissan Navara tarted up.
The 5 link rear coil suspension is already available on the upper end Navaras.I wonder if they have rear discs??? All the japer dual cabs run rear drums for some stupid idea.
You should try and stop a Holden Colarado with a full 400lt diesel tank on the back on a gravel or muddy road.The ABS is abysmal,they run seperate channels for the front discs and 1 channel for the rear drums,the fronts do all the work,ABS cuts in with little pedal effort,BLOODY DANGEROUS!!!!
Andrew


Rear drums have persisted mainly because they make it a lot easier to fit a handbrake, a problem that is solved differently with the Defender.

Although interestingly, the first family car to have discs (1955 Citroen) had drum rear brakes - and the handbrake operated on the inboard front discs! (Discs were very new at the time, and drums were considered adequate at the rear considering how little weight was on the rear wheels - front wheel drive and the rear wheels almost touch the bumper.)

John

I was under the impression that better braking was available from drums which is why the trucks still use them.

[isuzurover]

You people obviously haven't read that the new Disco has reinforced steel sub-frames.

Land Rover really love electrolysis between dissimilar metals...

[isuzurover]

I was under the impression that better braking was available from drums which is why the trucks still use them.

The short answer is no. Discs give better braking but drums are usually cheaper and easier to integrate with park/emergency braking systems as it takes less effort to actuate them.

A longer answer is here:
Brake Trends: Drums vs. Discs - Article - TruckingInfo.com (http://www.truckinginfo.com/article/story/2014/07/brake-trends-drums-vs-discs.aspx)

[JDNSW]

The other factor is that the available diameter for brakes is more limited (compared to the mass being braked) on trucks, but with drums you can increase drum and lining area by making it wider - and all the increase has the same leverage.

John

[scarry]

Toyota have just achieved their Ancap 5 rating on all their 70 series "tojos".

Land Rover will never capture the Australian market that Toyota will now be able to tap into.....specifically mining.

Only the tray back is 5 star,the rest of the 70 series model range is not.

[AndyG]

I suspect the wagons would fail the side impact test.
Interestingly Discovery 3 on the site but no 4, no Defender but then it's no longer sold

[frantic]

Simple answer for 5 v4 star on troopies is middle lap belt in 5 seats.
Pickles, IF the 99 td5 had patched in the D1 Airbag setup ( abs was available on defender from 99)it would have owned the mining market(toymota troopies only got those in the last 4 years) AND still be sold in the USA which would have resulted in double if not triple the sales.
The ranger was going to be the defender base but that marriage broke up before it went through. 130in chassis, U.K. Origin td5 , clamshell bonnet aka RRC, smaller diesel for Europe, etc the only thing missing from the ranga is a swb version and a 2.25 petrol 4cyl!:twisted:

[Pickles2]

Hey Frantic,....AGREE,...how's that!!
Pickles.

[Tombie]

Hey Frantic,....AGREE,...how's that!!

Pickles.



https://www.aulro.com/afvb/images/imported/2016/11/800.jpg

https://www.aulro.com/afvb/images/imported/2016/11/801.jpg

[AndyG]

How does the 3 door troopie with side sitting pax be legal in Oz, must admit have not looked in one here for years.

[Slunnie]

How does the 3 door troopie with side sitting pax be legal in Oz, must admit have not looked in one here for years.
I don't know how the center front seat can be legal either. I'm always hoping it's the gearstick I've just grabbed.

[scarry]

I don't know how the center front seat can be legal either. I'm always hoping it's the gearstick I've just grabbed.

They have recently removed that centre front seat in the Hi Ace for safety reasons.

[AndyG]

How does the 3 door troopie with side sitting pax be legal in Oz, must admit have not looked in one here for years.

To answer my question, it looks like the 3 door can be a 2 seater or a 5 seater.
We had a 5 seater, the front pax seat folds forward to allow rear access, pretty horrible. (from Toyota web site)

[Tombie]

Most mines won't allow side facing seats any longer.

[blackapache]

Most mines won't allow side facing seats any longer.

Ha - I've only worked on the worst underground mines... anything goes down there. We had a 12 seater with holes in the floor big enough to lose your crib bag through.

I always felt like Fred flinstone driving that thing:o

[scrambler]

Toyota's latest MY2017 70 Series pick up now has airbags & with other modifications achieved a 5 star ANCAP, but it is only the pick up, the troopie & wagon for some reason did not achieve the 5 star rating. I'm sure Land Rover could have done similar with the Defender! They will have lost a lot of business in the 2 year gap until the new Defender is available.

Land Rover no doubt looked at the Defender safety issues with the "new" dash in 2007 (remember that this was the first truly new dash since 1971!).

The issues I can see are 1) Chassis design (no crush cans/ location for them) and 2) minimal internal space. The second is the insurmountable issue - the space between the firewall and outside of the dash has not changed since 1958, when the dash was simply a metal shelf with metal instruments bolted to it. Arguably it didn't change a lot even then. It's not too surprising that they couldn't work 21st century technology into a 1950's dash design, when that design was "no dash."

I own an early Defender, with "factory" aftermarket AC - meaning the passenger door window winder handle cannot be held through 360 degrees. The AC outlet could either fit in the dash space taking away the vents (a la British cars and the Countys) or under the dash, taking away knee room and making winding a window difficult.

It needs to be remembered occasionally that the Series/County/Defender vehicles were designed to be built, by hand, from WW2 surplus; and that the core of the body design changed little from the mid-1950's to 2016. While there are plusses (such as fitting almost any age door to almost any age vehicle, with minor work) there are minuses, such as fitting new tech to your 50-60 year old design.

[Avion8]

Toyota did it quite simply by putting 5 airbags, including curtain & knee, a stiffer stronger frame, & high tensile steel side rails. I'm almost certain the envelope they had to work with was not much more than the Defenders, and was not exactly a new design having first been introduced in 1984, & of course it's predecessor had been around for 25 years before that.

I have noticed a lot of differences between my 1955 Series 1 to the 2000 TD5 110, and then on from that to my MY16 Puma 90.

[frantic]

Scrambler, have a look at a 98 Jeep Wrangler, less space(or Cherokee for that matter) than a defender between driver and wheel, the doors are far weaker, yet they got abs and a drivers airbag to enable continued sale in USA. The old box shape Cherokee had a fixed wheel that was far closer to the driver than a defender, but it still had airbags.
The d1 (and2)had a RRC chassis dating from the late 60's with crush cans /airbag sensors as an afterthought 25years later. Same drivetrain gear as a d90 or series 3 /2swb.