Just realized...WHOLE FRAME is made of high-tensile steel!

[Madtiger]

Call me a neophyte, but i just realized something when looking at Toyota website and older document (see link)...the whole entire frame of LC200 is made from high-tensile steel. (And the body itself is also made extensively of high tensile steel.)

From Toyota.com: "Unitized steel body on 10-member high-tensile-steel ladder frame"

Older document: https://newsroom.toyota.eu//service...hash=d7c0308c1c0f8d87eb5a1e947f93bd0f82d258bc

See Page 34-36.

High tensile steel frame + 10 cross-members (also high-tensile). Wow. Never realized that the WHOLE FRAME is ALL high-tensile steel. Pretty damn cool...and explains the high cost of LC/LX.

 

[CharlieS]

I take it that is a good thing?

 

[LBridges]

I take it that is a good thing?

Yes, until you wreck it. Then it needs special welding tools and processes.

@Madtiger - good find. I thought I read someplace else about high strength steel, but all I could find in a search today was from a 2018 press release. Which says: "The Land Cruiser’s rugged body-on-frame construction makes extensive use of high-strength steel – especially in the A-, B-, C-, and D-pillars, and rocker area...". That body info adds to your find on the frame.

I am 99% certain I've read more, I just can't seem to find it.

 

[HGB]

Yes, until you wreck it. Then it needs special welding tools and processes.

@Madtiger - good find. I thought I read someplace else about high strength steel, but all I could find in a search today was from a 2018 press release. Which says: "The Land Cruiser’s rugged body-on-frame construction makes extensive use of high-strength steel – especially in the A-, B-, C-, and D-pillars, and rocker area...". That body info adds to your find on the frame.

I am 99% certain I've read more, I just can't seem to find it.

How would this impact crash safety? I think of the steel bumper argument which centers around the trade-off of strength vs the ability to crumple and absorb energy. Thoughts?

 

[Supra88]

How would this impact crash safety? I think of the steel bumper argument which centers around the trade-off of strength vs the ability to crumple and absorb energy. Thoughts?

Documentation on the 200 shows and emphasis on increasing the rollover strength from the 100 series. I'm sure the material change and design changes in the A, B, C, and D pillars improve this. Not sure about impact crash safety.

 

[ArnieC]

High tensile steel isn't anything particularly special, just a different grade. Lots of reasons to use it. Could be to increase strength, could be to decrease weight, could be because of design constraints of something else needed both a small size and a high strength and well, Bob's your uncle!

Downside to some of the higher alloy steels is they are tougher to weld, requiring up to and including special filler materials, pre-heat, post-cool, and stress relieving. Also, without knowing exactly what alloy is used where, which would only typically be found on component level drawings or bills of material, it will be tough to figure out the truly proper weld procedure to do a repair.

 

[Madtiger]

I take it that is a good thing?

Yes. A very good thing. For example, the F150 frame (not body) is made from around 75% high-tensile steel. Of course, there are other criteria to frame strength such as thickness of steel, diameter, etc.. But high-tensile steel is generally more expensive.

Yes, until you wreck it. Then it needs special welding tools and processes.

@Madtiger - good find. I thought I read someplace else about high strength steel, but all I could find in a search today was from a 2018 press release. Which says: "The Land Cruiser’s rugged body-on-frame construction makes extensive use of high-strength steel – especially in the A-, B-, C-, and D-pillars, and rocker area...". That body info adds to your find on the frame.

I am 99% certain I've read more, I just can't seem to find it.

The FRAME is 100% high-tensile steel. The body makes extensive use of that steel grade like you stated above.

How would this impact crash safety? I think of the steel bumper argument which centers around the trade-off of strength vs the ability to crumple and absorb energy. Thoughts?

Remember, the frame and body do have crumble zones...so, the use of high tensile steel should not be a negative in crash testing. The strong frame allows for better durability over rough terrain and with towing.

High tensile steel isn't anything particularly special, just a different grade. Lots of reasons to use it. Could be to increase strength, could be to decrease weight, could be because of design constraints of something else needed both a small size and a high strength and well, Bob's your uncle!

Downside to some of the higher alloy steels is they are tougher to weld, requiring up to and including special filler materials, pre-heat, post-cool, and stress relieving. Also, without knowing exactly what alloy is used where, which would only typically be found on component level drawings or bills of material, it will be tough to figure out the truly proper weld procedure to do a repair.

It is special in the sense that it is stronger for same amount of steel. Strong yet lightweight relative to traditional steel. It is special because it is more expensive to make/weld/etc as you stated. It is special because i have not seen a frame made of 100% of high-tensile steel.

Given that LC200 is the strongest Toyota has ever made, bar none, i think that Toyota knows how to "handle" this grade of steel. Toyota has already stated how much stronger the LC200 frame is relative to LC100.

 

[Madtiger]

From the link above:

An all-new high strength, high rigidity frame has been designed to accommodate the Land Cruiser V8’s body. The chassis rail’s cross-sectional height and width have been increased to achieve a highly rigid structure, and high tensile steel is used to reduce weight without compromising strength.

New hydro-form technology has been employed to manufacture specific cross members. This has also increased the joint strength with the side rail, contributing to a frame structure with higher rigidity.

The new frame’s torsional rigidity is 1.4 times stronger than the outgoing Land Cruiser Amazon and flexural rigidity is 1.2 times greater.

An extra lightweight front suspension cross member has been added, and the coil support area of the front suspension strengthened for optimum performance.

High-tensile steel is used extensively throughout the body and has been treated for rust resistance across a broad range of the body panels to ensure durability, even in world’s harshest driving environments.

The chassis structure has been designed to absorb impact energy in the event of a collision and attention has also been focused on reducing injury risks to pedestrians. The bonnet structure is rigid but capable of absorbing impact energy, while the leading edge has an impact absorbing bead for effective performance in frontal collisions with smaller pedestrians, such as children. There are also impact-absorbing brackets between the side panels and the wing, and there is an open area between the rear of the bonnet and the windscreen, allowing the bonnet to move back in the event of a collision.

 

[Reckless]

Nice find! Makes me understand why I liked the 200 more than the 100 even though 100 handled better (albeit no leg room).

 

[Madtiger]

Given that LC200 is the strongest Toyota has ever made, bar none....

Hate to quote myself...but just in case anyone wanted to know where i got this factoid from...see:

top_10_used_overland_vehicles

overlandjournal.com

Click PLAY...go to time stamp: 41:33


And yeah......you're welcome.

 

[Reckless]

Saw this article just now on similar subject:
Toyota crapping their pants

 

[LBridges]

Found some info on types/alloys of HSS and where used in body and frame.

 

[OSS]

it's more of a buzz word than anything. High tensile steel only means they can use thinner material to get away with the same strength. If anything, it's a weight saving feature.

 

[slowride]

in the boot as part of the weight redistribution programme.

Other measures in this area include the optional carbon fibre roof, aluminium door skins mounted on a carbon fibre inner door structure and a composite boot floor. The LC 500 also represents Lexus’s most intensive use yet of high-strength steel, providing higher rigidity while reducing – and ideally positioning – vehicle mass to optimise dynamic performance. The result is a very balanced car with a near-ideal 52/48 front/rear weight distribution.


To achieve the targeted chassis performance, Lexus engineered the stiffest monocoque it has ever produced. Strategic use of lightweight, high-strength steel helps realise a high degree of torsional rigidity, with greater resistance to twisting forces than the carbon fibre-intensive LFA supercar.

Just depends on how much you want to spend... $$$$

The 200 Series is a 2000 - 2006 design... That was produced in 2007+

Imagine what the new 300 series will be when Lexus has the Rolls Royce Group in its sites...

Using 2020+ engineering and materials...

Save your nickels!!!

 

[Madtiger]

it's more of a buzz word than anything. High tensile steel only means they can use thinner material to get away with the same strength. If anything, it's a weight saving feature.

Maybe. Or Toyota used it for dual purpose. Stronger than before but without weight penalty.

Remember, LC200 frame is significantly stronger than LC100. And LC100 was no wet noodle.

And LC200 is no light foot either.

 

[Linh Pham]

What do you think about the new Mercedes G-wagen frame ? Can it compares to J200 frame ?
I read on its website that the frame is also high strength steel and have 3.4 mm in thickness. The structure also looked fantastic.

 

[Madtiger]

What do you think about the new Mercedes G-wagen frame ? Can it compares to J200 frame ?
I read on its website that the frame is also high strength steel and have 3.4 mm in thickness. The structure also looked fantastic.

I have not seen info on how thick LC frame is. But I am sure the new G frame is just as spectacular (or more). I doubt Mercedes cut any corners given its cost of entry.

 

[ziggym]

I wonder how the frames high tensile steel will be affected by a body mount chop to clear bigger tires. Is high tensile steel tempered? The cut shouldn't create too much heat but what about welding the most likely mild steel plate to cover the hole?

 

[TomEf]

I wonder how the frames high tensile steel will be affected by a body mount chop to clear bigger tires. Is high tensile steel tempered? The cut shouldn't create too much heat but what about welding the most likely mild steel plate to cover the hole?

These are good questions, unfortunately we don't really have all the info we need to answer 100%.

"High tensile" or "high strength" is totally arbitrary. Looking at the PDF, they're calling out sections as 340, 440, 490, 590, and 780MPa, which would be considered weak as hell in my industry. For my day job, I'd consider high tensile strength to start at about 1800MPa.

The quoted tensile strengths cast a pretty broad net that catches all sorts of steel alloys in the annealed/normalized condition, but I'm not gonna say if they've been heat treated for strength or not with any confidence. Any questions about welding are highly dependent on both the heat treat condition and the actual steel alloy in question, neither of which are known.

 

[HighRanch]

it's more of a buzz word than anything. High tensile steel only means they can use thinner material to get away with the same strength. If anything, it's a weight saving feature.

Don’t think Toyota took any shortcuts on the thickness of the chassis. (5mm on outer structure & 3.1mm on inner structure)