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Old 23rd August 2013, 22:09   #196
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Post Re: Driving all four wheels: how is it done?

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Originally Posted by .anshuman View Post

Fortuner does not have a 2wd mode. It is permanently in 4wd using center differential which also has a LSD, but both front and rear differentials are open. AFAIK in some markets Fortuner get a lockable center differential.
I think you wanted to say lockable rear differential, because in every market Fortuner 4x4 is marketed it is sold with lockable center differential.

This lockable center differential is torsen type (which is considered intelligent) in some countries like Malaysia but we in India don't get it.

AFAIK in no country Fortuner 4x4 is sold with anything other than lockable center differential.
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Old 23rd August 2013, 22:09   #197
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Default Re: Driving all four wheels: how is it done?

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No, in 4H mode SUVs like Safari, Scorpio, Endeavour... cannot be used on dry hard surface which does not allow the tires some slip. The reason is- A locking transfer case is used to split power delivery permanently, these vehicles so not have a center differential.

Now just because some vehicles like Fortuner, Pajero, Pajero sport.... have a center differential which enables them to have an extra mode where the vehicle can be used on roads in 4wd mode. This center differential can be locked for a fixed power split, when locked this center differential acts exactly like the locked transfer case i mentioned in the previous paragraph, for example this mode is called 4HL.

Fortuner does not have a 2wd mode. It is permanently in 4wd using center differential which also has a LSD, but both front and rear differentials are open. AFAIK in some markets Fortuner get a lockable center differential.

But most of the Off-roaders in our country use open differentials.
Thanks for shedding light, Anshuman.

I gathered this explanation from wiki -
"Transfer cases designed for off-road use can mechanically lock the front and rear axles when needed[3] (e.g. when one of the axles is on a slippery surfaces or stuck in mud, whereas the other has better traction). This is the equivalent to the differential lock."

So for a clearer understanding, this means that a Safari in 4H will be like a Fortuner having a locked center differential.

Also technically does that not make Safari's hardware more competent at least on paper, it has a rear LSD and a 4H means constantly powering front wheels irrespective when needed.

In the Indian Fortuner which has a LSD center diff, the rear should start slipping, if stuck, for the center diff to transfer power to front.
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Old 23rd August 2013, 22:10   #198
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by mroptimist View Post
I think you wanted to say lockable rear differential, because in every market Fortuner 4x4 is marketed it is sold with lockable center differential.

This lockable center differential is torsen type (which is considered intelligent) in some countries like Malaysia but we in India don't get it.

AFAIK in no country Fortuner 4x4 is sold with anything other than lockable center differential.
That was a typo, it has already been corrected.
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Old 23rd August 2013, 22:11   #199
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by s_pphilip View Post
Toyota Fortuner: has center diff, no LSD's in center, back or front. Full-time 4x4, has 4H and 4L gears.
Fortuner centre diff is a Torsen. Lockable too.

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Old 23rd August 2013, 22:14   #200
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Post Re: Driving all four wheels: how is it done?

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Fortuner centre diff is a Torsen. Lockable too.

Regards
Sutripta
No torsen in Indian Fortuner. Other countries (South Africa, Malaysia and Thailand) it is standard. It is lockable everywhere.
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Old 23rd August 2013, 22:16   #201
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by s_pphilip View Post
I gathered this explanation from wiki -
"Transfer cases designed for off-road use can mechanically lock the front and rear axles when needed[3] (e.g. when one of the axles is on a slippery surfaces or stuck in mud, whereas the other has better traction). This is the equivalent to the differential lock."
A locked Transfer-case is equivalent to locked center differential, though a transfercase there is no full time 4wd mode, its either 4wd locked or just 2wd.

Quote:
So for a clearer understanding, this means that a Safari in 4H will be like a Fortuner having a locked center differential.
Yes

Quote:
Also technically does that not make Safari's hardware more competent at least on paper, it has a rear LSD and a 4H means constantly powering front wheels irrespective when needed.
Yes the rear LSD gives it an edge, a slight advantage.


Quote:
In the Indian Fortuner which has a LSD center diff, the rear should start slipping, if stuck, for the center diff to transfer power to front.
There was a typo in my post, which i corrected some time back.

In Full Time 4wd mode(4H) the center differential acts like a normal LSD, that means diverts power to axle with lower slip.
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Old 24th August 2013, 00:12   #202
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Default Re: Driving all four wheels: how is it done?

These are the links to the videos about Tucson off roading, makes it feel invincible, though the truth is far from it:












In this video he tries to explain something with combinations between 4WD and ESC switched off.



How competent an AWD is depends on the driver and his luck, provided it has a 4x4 manual switch, just to illustrate a simple AWD too can be fun.

Last edited by s_pphilip : 24th August 2013 at 00:19.
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Old 24th August 2013, 10:32   #203
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by s_pphilip View Post
These are the links to the videos about Tucson off roading, makes it feel invincible, though the truth is far from it:

In this video he tries to explain something with combinations between 4WD and ESC switched off.

How competent an AWD is depends on the driver and his luck, provided it has a 4x4 manual switch, just to illustrate a simple AWD too can be fun.
Invincible? Nowhere near it! This pretty much soft roading stuff, show me where they need M/T tires or extra articulation or Low range. Any crossover with AWD and decent GC will do it.

In Video#1, the Tucson takes a dip in water crossing, they know exactly how deep it is. My XUV has crossed similar depth, i just had to watch another vehicle cross it.

In Video#2, the Tucson is wearing Snow chains on front tires, they make a hell lot of difference. This kind of terrain is what crossovers can do.

Do you think a Tucson/Santa-FE/Yeti/XUV can do this?





Without Low range, the clutch will go bust in first 2-3 minutes, in case of AT the transmission fluid will overheat.
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Old 24th August 2013, 21:10   #204
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by mroptimist View Post
No torsen in Indian Fortuner. Other countries (South Africa, Malaysia and Thailand) it is standard. It is lockable everywhere.
Was wondering why so many of us think that the India Fortuner has a LS centre Diff.

Anybody with an exploded view of the XFer case? And/ or parts catalogue numbers.

Regards
Sutripta
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Old 24th August 2013, 23:19   #205
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Sutripta View Post
Was wondering why so many of us think that the India Fortuner has a LS centre Diff.

Anybody with an exploded view of the XFer case? And/ or parts catalogue numbers.
Hmm... very, very interesting question. Stands many assumptions on their head.

Nowhere in Toyota Bharat's official webpages and specifications for India does the word *Torsen* appear. Nor does it appear on Toyota's Thai and Indonesian sites - though it makes an appearance on Toyota's Vietnam site: http://www.toyotavn.com.vn/news/views/200/1888.

However, it does appear in the South African and all Middle-Eastern countries' sites.

Related to India and the Far-Eastern countries, the only references to Torsen on the Fortuner that I could dig up were these:

http://www.chaocom.com/vietnam-car-c...7-seats-2.html - obviously not a technical or reliable site, considering it's a site for cars on hire;

http://toyotafortuner4x4.wordpress.c...cations-specs/ - but there the Torsen appears in conjunction with a 4-speed AT transmission - absolutely not India-spec.

So are there "Full-time 4wd" Fortuners with AND without Torsen centre diffs for different markets? Do the India-spec Fortuners have Torsen at all?

Last edited by SS-Traveller : 24th August 2013 at 23:25.
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Old 25th August 2013, 10:28   #206
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Default Re: Driving all four wheels: how is it done?

The thing to remember is that the nature of 4x4 running gear is an important factor, but only one among many others in how the car will cope off road. Overhangs/breakover angles, nature of the engine and its power and torque band, weight of the car, tyres - to name some - all play an important part and it is the complete package that delivers. Or not. Leaving aside the all important driver skill and experience.
The other thing to note is the having 4x4 capability can also breed a false sense of confidence which can be the undoing of the driver in leading him into a situation that can be embarrassing/inconvenient/dangerous. A more careful/skilled one with 2wd may fare better many times.
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Old 25th August 2013, 12:03   #207
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by mroptimist View Post
No torsen in Indian Fortuner. Other countries (South Africa, Malaysia and Thailand) it is standard. It is lockable everywhere.
What's your source? Absence of evidence = evidence of absence? You seem to be making authoritative comments. Is that based merely on Google expertise or you have some special information that even some of the owners are not privy too?

Btw, here's GTO's test drive/review post from 2009:
http://www.team-bhp.com/forum/offici...ml#post1467341

Quote:
Originally Posted by Sutripta View Post
Was wondering why so many of us think that the India Fortuner has a LS centre Diff.

Anybody with an exploded view of the XFer case? And/ or parts catalogue numbers.

Regards
Sutripta
I wonder why so many are quick to start conjecturing about the lack of Torsen in the Fortuner. Just because the dumbed down Indian website - which focuses more on bling aspects - doesn't mention that? The Indian website doesn't mention many things such as the crawl ratios, wading depth etc. The average Fortuner buyer cares zilch about details of the 4WD system. And most service centre folks don't have a clue.

The older Indian Fortuner was exactly the same as the older South African Fortuner (the 2009 version) apart from lack of VSC and rear diff lock. I can't comment about the new 4X4 Fortuner.

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Originally Posted by SS-Traveller View Post
Hmm... very, very interesting question. Stands many assumptions on their head.

Nowhere in Toyota Bharat's official webpages and specifications for India does the word *Torsen* appear. Nor does it appear on Toyota's Thai and Indonesian sites - though it makes an appearance on Toyota's Vietnam site: http://www.toyotavn.com.vn/news/views/200/1888.

However, it does appear in the South African and all Middle-Eastern countries' sites.

Related to India and the Far-Eastern countries, the only references to Torsen on the Fortuner that I could dig up were these:

http://www.chaocom.com/vietnam-car-c...7-seats-2.html - obviously not a technical or reliable site, considering it's a site for cars on hire;

http://toyotafortuner4x4.wordpress.c...cations-specs/ - but there the Torsen appears in conjunction with a 4-speed AT transmission - absolutely not a India-spec.

So are there "Full-time 4wd" Fortuners with AND without Torsen centre diffs for different markets? Do the India-spec Fortuners have Torsen at all?
Torsen is used in all fulltime 4WD Toyota SUVs. A fulltime 4WD SUV without LSD? The older Fortuner and the Grand Vitara use similar setups.

Don't go by what is there on the Toyota website - which is pretty basic and catering to the 'image and presence' crowd. In fact the website has become worse than what it was a few years back. The vehicle sells by itself, so the marketing folks don't bother creating an informative web presence.
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Old 25th August 2013, 15:03   #208
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Post Re: Driving all four wheels: how is it done?

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Originally Posted by nilanjanray View Post
What's your source? Absence of evidence = evidence of absence? You seem to be making authoritative comments. Is that based merely on Google expertise or you have some special information that even some of the owners are not privy too?

Btw, here's GTO's test drive/review post from 2009:
http://www.team-bhp.com/forum/offici...ml#post1467341
I apologise if my post is taken as "Authoritative". I am far from an authority on anything on wheels, let alone 4x4 vehicles which are anyway quite complex to understand.

I agree that I committed a mistake by not mentioning the source.

So please enlighten us on what should be taken as definitive evidence. How about a poll among owners? or a piece of paper provided by Toyota Kirloskar Motors or some other holy book.

One more disclaimer I am not an expert on googling either.

Quote:
Originally Posted by nilanjanray View Post
I wonder why so many are quick to start conjecturing about the lack of Torsen in the Fortuner. Just because the dumbed down Indian website - which focuses more on bling aspects - doesn't mention that? The Indian website doesn't mention many things such as the crawl ratios, wading depth etc. The average Fortuner buyer cares zilch about details of the 4WD system. And most service centre folks don't have a clue.

The older Indian Fortuner was exactly the same as the older South African Fortuner (the 2009 version) apart from lack of VSC and rear diff lock. I can't comment about the new 4X4 Fortuner.
Did you own the South African Fortuner? If the answer is no how can you comment on that either.

You can't comment about the new 4x4 Fortuner because you don't own one or is it due to some other reason.

Quote:
Originally Posted by nilanjanray View Post
Torsen is used in all fulltime 4WD Toyota SUVs. A fulltime 4WD SUV without LSD? The older Fortuner and the Grand Vitara use similar setups.

Don't go by what is there on the Toyota website - which is pretty basic and catering to the 'image and presence' crowd. In fact the website has become worse than what it was a few years back. The vehicle sells by itself, so the marketing folks don't bother creating an informative web presence.
What is your source that torsen is used in all fulltime 4WD Toyota SUVs, some website a book or some other secret owner's network only you guys are privy to?

If you say we cannot go by Toyota website what other source we should use to get enlightened. Is there any other method available to gain knowledge about vehicles apart from "owning" a vehicle. Because I don't have resources to own all or many vehicles.

If you keep questioning every source as incomplete or wrong then what is the source of information of GTO's post, TKM or Team-BHP has a secret diagnostic device which when applied to a car gives accurate info about a car which then can't be contested.

Sorry for the long rant.
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Old 25th August 2013, 15:14   #209
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Default Re: Driving all four wheels: how is it done?

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Torsen is used in all fulltime 4WD Toyota SUVs. A fulltime 4WD SUV without LSD?
Why not? Since it's also equipped with a diff lock (4HL), how would it be disadvantageous to not have a Torsen LSD?

No one has physically confirmed the presence of Torsen in any Fortuner sold in India - or have they? - and Toyota is quite silent about the existence of the same on its Indian models. Nilanjan, Sutripta, anybody else, can you please confirm whether *Torsen* appears in the owner's manual with you? Please post an image of the same if possible.
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Old 25th August 2013, 15:36   #210
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Default Re: Driving all four wheels: how is it done?

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Originally Posted by mroptimist View Post
If you keep questioning every source as incomplete or wrong then what is the source of information of GTO's post, TKM or Team-BHP has a secret diagnostic device which when applied to a car gives accurate info about a car which then can't be contested.
Does this help?

http://www.toyota.com.kw/english/toy...erformance.asp

Also, search for LSD in the following brochure: http://www.toyota.co.za/picturedata/...ae76e576dc.pdf

They can't remove LSD from a fulltime 4WD. Guess what happens if you have an open center diff?

Explained here: http://www.team-bhp.com/forum/offici...ml#post2488854

Take a 2WD car and a 4WD car with open center diff. Both will be stranded, if one wheel loses traction. Now all the Indian Fortuner owners can confirm whether they were stranded when one wheel was slipping, when they hadn't locked the diff.

Last edited by Samurai : 25th August 2013 at 15:47.
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