Monocoque vs Ladder Chassis in SUVs: Advantages & Disadvantages!

[THE XOVER]

According to me:

Advantages of BOF over Monocoque structure

• Can tackle bad roads better.
• Much better for off-roading.
• Repair bills are much less when it comes to damage control after hardcore off-roading.
• Accident repair is also less because of separate chassis and body.

Advantages of Monocoque structure over BOF:

• More light,hence fuel efficient.
• More safe because of integrated chassis/body.
• Better handling.
• Much better in ride comfort.

These are my views,what other TAIans think? Please contribute to this important topic,it may help common man understand the difference between a real and psuedo SUV.Thanks.



THE X-OVER

 

[jayadev]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

BOF is at end of its tether considering smaller personal use vehicals.

manufacturer pursue on BOF as it is less technically involving than any other (read cheaper overall investements.)

 

[Theferrarifan]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

Xover you got everything covered but still I am posting-

The monocoque is a lighter design which is a plus for efficiency, it has more torsional stiffness and is by far the better chassis for performance oriented vehicles. But SUVs are not performance vehicles so[thinking]
The heavy nature of the ladder chassis makes it tough and it better than the monocoque for carrying heavy loads or offroading.
Monocoque chassis are obviously much harder to design. Ladder on frame are easier to design and modify.
Materials: Well monocoque chassis can be built using a variety of materials like carbon fibre(Enzo), aluminium(Jag XJ) which further improves the strength and decreases the weight.
Safety- monocoque is safer. You can have crumple zones in a monocoque but not on LOF. But as xover said,easier to repair.

 

[jayadev]

Xover you got everything covered but still I am posting-

The monocoque is a lighter design which is a plus for efficiency, it has more torsional stiffness and is by far the better chassis for performance oriented vehicles. But SUVs are not performance vehicles so[thinking]
The heavy nature of the ladder chassis makes it tough and it better than the monocoque for carrying heavy loads or offroading.
Monocoque chassis are obviously much harder to design. Ladder on frame are easier to design and modify.
Materials: Well monocoque chassis can be built using a variety of materials like carbon fibre(Enzo), aluminium(Jag XJ) which further improves the strength and decreases the weight.
Safety- monocoque is safer. You can have crumple zones in a monocoque but not on LOF. But as xover said,easier to repair.

why should you think that a monocoque cannot be toughned for offroad purpose and abuse?

Best part which impress me is eco friendliness.

 

[Theferrarifan]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

why should you think that a monocoque cannot be toughned for offroad purpose and abuse?

Because thats impractical. Abuse will obviously cause a lot of damage to the chassis in offroading,and changing the complete chassis is not cheap and completely repairing it very hard if not impossible.

 

[jayadev]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

Because thats impractical. Abuse will obviously cause a lot of damage to the chassis in offroading,and changing the complete chassis is not cheap and completely repairing it very hard if not impossible.

Hold on please.

very purpose of MCq or unishell body is to reduce weight incidently production cost.
Who on earth would like to make it tougher and heavier unless for a purpose?

E.g,Have you noticed some difference between a Fiat Punto and Suzuki swift?

offroaders and heavy duty cars are not mass sellers ,hence nobody bothers for a hefty investement .

 

[Theferrarifan]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

Hold on please.

very purpose of MCq or unishell body is to reduce weight incidently production cost.
Who on earth would like to make it tougher and heavier unless for a purpose?

E.g,Have you noticed some difference between a Fiat Punto and Suzuki swift?

offroaders and heavy duty cars are not mass sellers ,hence nobody bothers for a hefty investement .

Jaydev,thats what I was saying. Whats the point of adding strength to the M.C.?
And heavy duty dont sell here,but they do in the states.

 

[THE XOVER]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

Disadvantages of Ladder frame chassis

1. Makes the vehicle too ponderous thus negatively affecting efficiency and performance.

2. Making a safe vehicle compatible for Euro NCAP ratings is much more tougher and expensive.(for eg,it's much easier and less expensive for a vehicle like XUV to be ENCAP compatible,but it's much more expensive for a BOF vehicle like Tata Aria to be ENCAP compatible as you need to add extra crumple zones to stiffen the chassis,which in a monocoque you can design by default:hence adding more weight,metal which costs more eventually)

3. Less eco friendly because of their weight.

4. Poor ride vis-a-vis monocoque(though Storme and Aria are exceptions).


Disadvantages of Monocoque structure

1.Too fragile during extreme off-roading.

2. After accident you may need to completely change the body as it's part of the chassis.(In ladder chassis vehicles you can just change the damaged part and be happy.)


To be honest there are not too many disadvantages of unibody stucture as it's the way forward.Slowly but surely in perhaps next 20 years Ladder chassis based vehicle may become "extinct species",lol.

 

[jayadev]

Jaydev,thats what I was saying. Whats the point of adding strength to the M.C.?
And heavy duty dont sell here,but they do in the states.

I was refering to your Impracticality point which isnt the reason.
Some Manufacturer wouldnt be interested.

e.g,Mahindra xuv as a unishell can be modded to a serious offroader which is no big deal.
it can be designed to take serious beating which any other BOF can endure.
but point is SUVs are not offroaders.
In modern days people are turning towards austerity (so much of crisis) which deliberatly calls for lighter fuel efficient cars without compromising performance.

 

[jayadev]

Disadvantages of Ladder frame chassis

1. Makes the vehicle too ponderous thus negatively affecting efficiency and performance.

2. Making a safe vehicle compatible for Euro NCAP ratings is much more tougher and expensive.(for eg,it's much easier and less expensive for a vehicle like XUV to be ENCAP compatible,but it's much more expensive for a BOF vehicle like Tata Aria to be ENCAP compatible as you need to add extra crumple zones to stiffen the chassis,which in a monocoque you can design by default:hence adding more weight,metal which costs more eventually)

3. Less eco friendly because of their weight.

4. Poor ride vis-a-vis monocoque(though Storme and Aria are exceptions).


Disadvantages of Monocoque structure

1.Too fragile during extreme off-roading.

2. After accident you may need to completely change the body as it's part of the chassis.(In ladder chassis vehicles you can just change the damaged part and be happy.)


To be honest there are not too many disadvantages of unibody stucture as it's the way forward.Slowly but surely in perhaps next 20 years Ladder chassis based vehicle may become "extinct species",lol.

Bof frame can quickly fail due to fatigue cracks and torsional stress where as UShell can be designed intelligently for even distribution and much better stress relief features.

Obviously heavier ones wears your tires and bearings, axles quickly than lighter ones.no brianer.

 

[Iron Rock]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

To be honest there are not too many disadvantages of unibody stucture as it's the way forward.Slowly but surely in perhaps next 20 years Ladder chassis based vehicle may become "extinct species",lol.

Xover what about the mixed breeds ? the likes of Montero's/Vitara's

 

[jayadev]

Xover what about the mixed breeds ? the likes of Montero's/Vitara's

Hope I am allowed to add my 2cents.

Goodness of both chasis being exploited here.

Better NVH of BOF and positives of Ushell in agility and handelling.

but it would be bit expensive from production point .

hence it would remain in exotic car realms only.

 

[navnit013]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

@ jayadev, The frame is built to last. You need a huge load to crack a ladder frame. It wont bend and deform like the monocoque.

Monocoque has its advantages. In a few decades, monocoque will replace every thing that is built on ladder frame today. Monocoque is light, and easy to build. And can withstand every day abuse and is much much safe in a crash.

BUT at present BOF is a way to go, as far as UVs are concerned. The hydroformed ladder frame that Aria, now the Safari, innova and fortuner use, are a lot light and much stiffer/rigid compared to the old ladder frame. Their handling characteristics can be made to match that of the monocoques.

The only thing that will drive the BOFs out of business is their weight. NO MATTER what you do BOF will be heavier than the monocoque. AND one day the green brigade will drive them into extinction.

 

[jayadev]

@ jayadev, The frame is built to last. You need a huge load to crack a ladder frame. It wont bend and deform like the monocoque.

Monocoque has its advantages. In a few decades, monocoque will replace every thing that is built on ladder frame today. Monocoque is light, and easy to build. And can withstand every day abuse and is much much safe in a crash.

BUT at present BOF is a way to go, as far as UVs are concerned. The hydroformed ladder frame that Aria, now the Safari, innova and fortuner use, are a lot light and much stiffer/rigid compared to the old ladder frame. Their handling characteristics can be made to match that of the monocoques.

The only thing that will drive the BOFs out of business is their weight. NO MATTER what you do BOF will be heavier than the monocoque. AND one day the green brigade will drive them into extinction.

its not only green brigade but manufacturer themselves would refrain from high maintenance products.

lighter cars are pocket friendly and more fun.

 

[jagrover]

Re: Monocoque V/S Ladder Chassis in SUVs: Advantages & Disadvantages!

Monocoque can handle off roading..
Eg;Range Rover Am I correct..