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Old 20th October 2012, 12:21   #1
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Default Modern SUVs : Spare wheel placement & interior / mechanical packaging

Question 1:

Why don't modern SUV's have the spare wheel mounted on the tailgate? What advantages does a spare wheel mounted on the underside of the chassis offer?

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The new trend seems to ruin the looks of a SUV and make it look like a bloated hatchback. And I guess extricating the tyre whenever there is a puncture is a bit of a hassle too.


Question 2:

How does a 4.4 metre sized MUV manage to fit in 7 people with decent comfort while most SUVs (some stretching to even 5 metres) barely manage to accomodate school kids in the third row seats?

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What goes into "space packaging" of a typical MUV?


Question 3:

The Aria's bonnet/engine bay looks (visually) smaller than the new Safari's bonnet/engine bay. Both the cars are run by the same 2.2 litre engine, mounted longitudinally. How did that happen?

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Ditto with Xylo/Scorpio.

(Innova's engine bay/bonnet is smaller than that of the Fortuner, but then its engine displacement is lower than that of Fortuner).

Last edited by smartcat : 22nd October 2012 at 17:24. Reason: Edited the thread's content as suggested by GTO.
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Old 21st October 2012, 22:41   #2
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

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Originally Posted by smartcat View Post
Why don't modern SUV's have the spare wheel mounted on the tailgate? What advantages does a spare wheel mounted on the underside of the chassis offer?
A tail-gate mounted spare wheel looks great in most cases.

However, its a herculean task to not only remove the spare from the high mount, but also put the punctured wheel back on there (assuming you don't have enough storage elsewhere).

I guess it could be easy to drop it on your foot too. I wonder if liability comes into play. Also, most places in America (home of the urban SUV!) have a large number of SUVs being driven by women.

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Originally Posted by smartcat View Post
How does a 4.4 metre sized MUV manage to fit in 7 people with decent comfort while most SUVs (some stretching to even 5 metres) barely manage to accomodate school kids in the third row seats? What goes into "space packaging" of a typical MUV?
I think it comes down to two things:
1) Interior packagine (eg. "MUVs" might squeeze people in with just enough space, whilst SUVs are more spacious for less people).
2) MUV's Transverse/FWD layout vs a SUV's Longitudinal/RWD layout. Just look at the length of the Endeavour's hood compared to that of the Xylo. All that extra length saved on the Xylo has been converted into cabin space.

Last edited by GTO : 23rd October 2012 at 09:32. Reason: Last question removed to keep the thread focussed
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Old 21st October 2012, 23:36   #3
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

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Originally Posted by Rehaan View Post
2) MUV's Transverse/FWD layout vs a SUV's Longitudinal/RWD layout.
Evalia & Ertiga are FWDs, but Innova, Xylo and Aria are still RWDs, right?

Quote:
Just look at the length of the Endeavour's hood compared to that of the Xylo. All that extra length saved on the Xylo has been converted into cabin space.
Bingo! Never noticed that before.

Last edited by GTO : 23rd October 2012 at 09:33. Reason: Quoted post deleted
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Old 21st October 2012, 23:53   #4
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

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Originally Posted by smartcat View Post
Evalia & Ertiga are FWDs, but Innova, Xylo and Aria are still RWDs, right?
Yeah, sorry about that. I actually had that thought about sedans a few weeks back (3-series vs something else) and blindly re-posted/confused it over here.

I guess you could just attribute it to body style. 1-ish box vs 2-box.

cya
R

Last edited by Rehaan : 23rd October 2012 at 12:05.
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Old 21st October 2012, 23:55   #5
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

With regard to the tail gate mounted spare wheel, I think the rear door needs to be much stronger to take that extra weight. So in a way not having the tire there means you can get away with a lighter door. Saves on material and also makes it easier to open and close the the door.
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Old 22nd October 2012, 07:19   #6
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

As far as long cars having proportionally smaller cabin space, there is one more reason. Earlier, cars were designed to carry engines with various capacities, to suit different power requirements.

The design had to accommodate these powerful (naturally aspirated) engines. For example, see the bonnet of a Palio or even Polo.

Things were only worse n longitudinally mounted engines.

However, things are changing, thanks to improved direct injection technology, turbochargers and increasing emission norms. You can have the same small block with varying power outouts (e.g, MultiAir, Ecoboost).
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Old 22nd October 2012, 17:36   #7
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Default re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

Regarding my new "question 3", I'm adding pictures of Xylo and Scopio - the relative bonnet size difference is much clearer with these two cars. How did Mahindra magically fit in the mHawk/mEagle engine into the (visually) tiny engine bay of the Xylo? Why does the same engine need a larger engine bay/bonnet in the Scorpio?

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Last edited by GTO : 23rd October 2012 at 09:36. Reason: Taking Live
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Old 2nd July 2013, 16:51   #8
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Default Why I love the sub 4 metre SUVs

It was started by the Premier Rio, followed by the Mahindra Quanto and now the Ford EcoSport, I am increasingly growing fond of the sub 4 metre SUV’s not because they are value for money, not because they offer the practicality of an SUV at the price of a hatch and not because I am a Duster/Scorpio/Safari troll.

I like them simply because, they are playing a big role in bringing back the trend that has for ages defined SUV’s and given them their character—the tailgate mounted spare wheel!

I know that manufacturers have been forced to take this route due to the length constraints but I am not complaining.

And the launch of EcoSport has made me more ecstatic because for me it is the first proper mini SUV in India unlike the Rio which is a ‘vintage’ product and looks its age or even the Quanto, which has the genes of the ugly Xylo.

The EcoSport’s looks and design has already become the talk of the town and as it goes on to becomes a huge success, other automakers will notice and scrutinize each and every aspect of its success.

And with Indians love for SUV’s only headed north, more and more manufacturers like Honda, Hyundai, Suzuki have pulled up their socks to exploit this niche segment and their mini SUV’s will be having the rear mounted spare wheel too.

However, it’s the category above that which is not bound by this rule that I hope gets influenced by the EcoSport’s success. Maybe the next generation Scorpios/Safaris/Dusters/Terranos and even the Fortuners would be more brute looking.

And it’s not just about the looks, the rear mounted tyres also help in breaking the mass of a SUV’s which tend to have longand flat rear doors. For example take the Quanto and the Xylo and compare their rears, you will get my point.

In fact I have seen some modified Scorpio’s with rear mounted wheels and they looked AWESOME!

I've heard arguments that the wheels make the rear doors heavy but seriously how many of use our rear doors daily? Moreover, it isn't that the tyre weighs a 100 pounds and makes to door unable to operate.

Since childhood, the definition of an SUV for many of us was the good old Maruti Suzuki Gypsy, Mahindra Jeep, Armada, Bolero, Tata Sierra, Sumo, Safari and even the Willy's Jeep with rear mounted wheel always being there hallmark. Though, the Tata Estate was an exception.

Among the premium SUV’s, the Mitsubishi Pajero and Ford Endeavour sported the spare wheel and thankfully continue to do so.

But sadly, after the launch of the hugely popular Mahindra Scorpio, I feel this trend changed somewhat. Maybe, its success affected the thinking of the people at not only Mahindra whose future models like the Xylo and XUV 5OO had plain rears but also Tata as it removed the tail mounted spares from their Sumo and Safari range.

I mean it is okay for MUV’s like Qualis, Ertiga, Innova, Enjoy to have clean backs. In fact they would look silly with a rear mounted spare. But not SUV’s. After all they should have a distinct character.

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Last edited by Eddy : 2nd July 2013 at 21:35. Reason: Note Inline
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Old 3rd July 2013, 20:41   #9
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Default Re: Why I love the sub 4 metre SUVs

Agree on the rear mounted wheel. I prefer the old safari's looks to the storme's.
And looks wise, a gypsy king soft top still smokes these newer SUVs IMHO. I like the looks of the ecosport, no doubt, but park it next to the king ... well, no prizes for guessing my preference ! :-)
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Old 4th July 2013, 03:51   #10
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Default Re: Why I love the sub 4 metre SUVs

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Originally Posted by captain.torque View Post
I've heard arguments that the wheels make the rear doors heavy but seriously how many of use our rear doors daily? Moreover, it isn't that the tyre weighs a 100 pounds and makes to door unable to operate.
Rear doors being heavier has much more implications than just being more difficult to open and close it. A heavy rear door would mean, thicker material for construction, a stronger set of hinges, much sturdier dampeners etc. Not to speak of the higher possibility of rattling if any of these are compromised.

In addition, it is much mode difficult to lift off/on the spare tire from that height in case of puncture. And this simply adds up as the tire size increases. So relatively easier with 15R Ecosport, but not the same with a 17R Fortuner.

Having said this, I personally likes the rear mounted wheel look for an SUV, but the advantages are more or less equally balanced out with the disadvantages.
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Old 4th July 2013, 15:25   #11
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Default Re: Why I love the sub 4 metre SUVs

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Originally Posted by sarathlal View Post
Rear doors being heavier has much more implications than just being more difficult to open and close it. A heavy rear door would mean, thicker material for construction, a stronger set of hinges, much sturdier dampeners etc. Not to speak of the higher possibility of rattling if any of these are compromised.
Thanks for the info Sarath. But I beg to differ on your second point. Unfortunately, I have changed the tyres on both-- the safari (uncle's) and the Scorpio (brother's) and removing the Scorpio's spare tyre was a pain in the neck especially when the boot was loaded with luggage.

If I have to change my punctured tyre with a spare, I would prefer my SUV to have a rear mounted spare wheel anyday.

But sadly, all the 'bigger' SUV's are shying away from this trend now. I pray that the next gen Endeavour carries on the legacy and maybe i'll buy one
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Old 5th July 2013, 13:29   #12
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Default Re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

Wouldn't the door a mounted wheel also increase the centre of gravity a little bit? Making it a tiny bit more unsafe for tall vehicles?

I love the rear mounted wheel look though. The Fortuner would have looked awesome with that look :-)
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Old 5th July 2013, 14:47   #13
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Default Re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

Quote:
Originally Posted by smartcat View Post
Regarding my new "question 3", I'm adding pictures of Xylo and Scopio - the relative bonnet size difference is much clearer with these two cars. How did Mahindra magically fit in the mHawk/mEagle engine into the (visually) tiny engine bay of the Xylo? Why does the same engine need a larger engine bay/bonnet in the Scorpio?
Xylo being an MUV has a transversely mounted engine or in simple words the engine is placed horizontally to accommodate more interior space whereas in SUV's a long bonnet adds to the macho look and is a must so the engine is placed longitudinally or vertically.

Please correct me if I am wrong friends.
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Old 5th July 2013, 15:20   #14
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Default Re: Why I love the sub 4 metre SUVs

Quote:
Originally Posted by sarathlal View Post
Rear doors being heavier has much more implications than just being more difficult to open and close it. A heavy rear door would mean, thicker material for construction, a stronger set of hinges, much sturdier dampeners etc. Not to speak of the higher possibility of rattling if any of these are compromised.

In addition, it is much mode difficult to lift off/on the spare tire from that height in case of puncture. And this simply adds up as the tire size increases. So relatively easier with 15R Ecosport, but not the same with a 17R Fortuner.

Having said this, I personally likes the rear mounted wheel look for an SUV, but the advantages are more or less equally balanced out with the disadvantages.
Yes. There is a large number of pre-STORME Safari users, who have even a door tilt problem. The hinge really has to be real strong as the whole wheel + door's weight lies on those 2 points. And with day to day use on jerky roads, the hinge does take a beating with all this weight.
The door structural stability, ease of handling the heavy wheel for replacement AND of course cost cutting by avoiding the high grade door fittings are primary reasons for the spare wheel disappearing from the rear door.

Quote:
Originally Posted by captain.torque View Post
Xylo being an MUV has a transversely mounted engine or in simple words the engine is placed horizontally to accommodate more interior space whereas in SUV's a long bonnet adds to the macho look and is a must so the engine is placed longitudinally or vertically.

Please correct me if I am wrong friends.
Absolutely right. That horizontally mounted engine is the primary contributor to a car (MPV) with same total length having a significantly larger cabin space compared to an SUV. In other words, known as a "cab forward" design.

Last edited by Reinhard : 5th July 2013 at 15:27.
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Old 5th July 2013, 15:45   #15
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Default Re: Modern SUVs : Spare wheel placement & interior / mechanical packaging

Quote:
Originally Posted by Rehaan View Post
A tail-gate mounted spare wheel looks great in most cases.

However, its a herculean task to not only remove the spare from the high mount, but also put the punctured wheel back on there (assuming you don't have enough storage elsewhere)..
Tata Safari used to suffer from tailgate rattle which developed due to weight of the wheel on the back. It was a hit or miss fix.
By removing the wheel from the back you can use weaker mounts without any rattle or alignment problems. That was the primary motivation from removing the wheel from the tail gate. A 16" 235/70 wheel with tire(even if alloy) weighs over 25kgs!
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