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Old 19th January 2008, 15:56   #46
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It is true that 4WD is not to be used on metalled roads as it is seriously meant for off-roading. But nowhere nobody mentioned that it can be used to get out of a sticky situation, metalled or unmetalled roads not withstanding.

While going to Lal Tibba above Mussoorie I encountered nearly 30 deg incline. I could be wrong but indeed it was a steep climb and I saw many a vehicle including a couple of lancers, omnis and a tavera going up a few distance and then loosing power and rolling back. I also tried in my safari in 2WD mode and midway the engine nearly stalled.

It was a metalled road and I had to engage 4H to climb up. When I returned back I went to garage get it checked for any damage to tranny & differential. There was none and I was assured that if at all one gets into a sticky situation 4WD can be used.

Like all others said it shouldn't be used over a long distance at a speed on metalled surfaces.
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Old 19th January 2008, 15:57   #47
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Answer - B

with lockable differential.

Quote:
Originally Posted by Torque-ative View Post
So which is more capable off the road .

A) A 4wd with front and rear diff. only
B) A 4wd with front, rear and central diff.

Pardon if obvious,..still wanted to know from the experts !!
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Old 19th January 2008, 16:29   #48
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Quote:
Originally Posted by tsk1979 View Post
When the Tata guys say shift on the fly Bosch Wargner Transfer case, what do they mean?
Hi Tsk!
Its actually Borg and Warner.
They are pioneers in manufacturing transmission assemblies,clutch system modules,transfer cases,turbochargers and the like.
The Safari 4x4 comes with an analogue of this....
BorgWarner Corporate Site - Products/TorqTransfer Systems/Transfer Case
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Old 19th January 2008, 16:33   #49
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Quote:
Originally Posted by Alfa_Kilo View Post
One word of caution with the Safari 4x4: If one does not engage the electric TCase for a while, the motor tends to get stuck. I know a couple of cases where 4x4 was not engaged for over a year and it got stuck in 4x2.
True.My mechs warned me too.
Thats reason enough for me to mud wrestle once in 3 months...
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Old 19th January 2008, 16:57   #50
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If you dont get a chance to go off road , just drive in a straight stretch for 60 - 90 seconds , in 4x4 and then pull over, put it in 4 Low and drive for 10 meters or so , and then move to 2H and drive normaly.

I do this even with my manual transfer case, to make sure the gear dogs dont get rusted etc. Usualy during sunday morning 7.30 AM , when the traffic is less
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Old 21st January 2008, 15:02   #51
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yep, my kids do have a weak stomach. How much of a bother is this for your kids?


Quote:
Originally Posted by jyobeb View Post
[QUOTE Thanks for this reassurance..i was actually quite concerned with Endeavour drive that i had done... if the safari behaves much better, then its a good thing for me
I have a DICOR 3.0 4WD. The 4WD Safari definitely has a firmer ride than the 2WD. The 2WD is much more pliant and feels better to travel in.
The 4WD definitely has less body roll.
However, all Safaris' have that gentle bobbing even on good roads, which can make any person who has a weak stomach, get car sick. Ask my wife, my 9 year old son and my 2 year old daughter!!!!!
I would suggest a small trip on a friends Safari, in the rear seat, before you decide.[/quote]
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Old 21st January 2008, 15:12   #52
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looks like i need to do a TD sitting in the rear seat to figure out if this rocking is enough to trigger a motion sickness..... Thanks for this input...very valuable.

Quote:
Originally Posted by dadu View Post
I wouldnt say on "good roads" but on potholes and speed breakers it does rock a bit, but there is also a trick to avoid it too. There's a sweet point in the suspension.

Yes, if you drive too slow over them, you will feel the rocking, you anyways cant drive too fast , but if you keep arpund 25-35, you wont feel any of it, its smooth sailing (dont try this on the big breakers, rumblers is still ok)
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Old 22nd January 2008, 00:22   #53
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Quote:
Originally Posted by rrnsss View Post
If you dont get a chance to go off road , just drive in a straight stretch for 60 - 90 seconds , in 4x4 and then pull over, put it in 4 Low and drive for 10 meters or so , and then move to 2H and drive normaly.

I do this even with my manual transfer case, to make sure the gear dogs dont get rusted etc. Usualy during sunday morning 7.30 AM , when the traffic is less
Don't forget to reverse about 20 feet after all that, to disengage your freewheeling hubs!
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Old 22nd January 2008, 00:25   #54
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Quote:
Originally Posted by jyobeb View Post
Don't forget to reverse about 20 feet after all that, to disengage your freewheeling hubs!
I don't think his Judo has free-wheeling hubs.
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Old 22nd January 2008, 15:06   #55
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Quote:
Originally Posted by xbox360 View Post
Not sure about ride comfort, but have been told that the 4WD has lesser body roll.
I dont think there is any difference between 4WD and 2WD w.r.t body roll UNLESS the suspension settings are different..viz. 2WD has independent front suspension and 4WD has leaf springs..

Even then the leaf springs tend to have more body roll!

Quote:
Originally Posted by DirtyDan View Post
I was a test driver for Dana-Spicer, one of the largest four wheel drive and differential manufacturers in the world for about 3.5 years. In that time I happily destroyed many test vehicles. Two in particular by running them in four wheel drive on dry pavement. The tranny in one lasted 400K the other lasted just under 200K. First the trannys got very, very hot vaporizing and burning all the tranny oil within. Then the gears and bearing got hot. Then...they stopped working.
Lucky Dirtydan..How I ENVY you..

Quote:
Originally Posted by tsk1979 View Post
From the above discussion it appears that unless you have a limited slip center differential which allows different speeds of front and rear axles, 4WD should be used only then you are stuck, or you are driving on slush where there is high probability of getting struck in slush.
On rocky terrain, where there are just big rocks and not much slush, 4WD mode may actually lead to damage?!
When Big rocks are there..4wd is necessary.. 2 reasons.. in 2WD the power will spin the wheels which can damage the vehicle..

with 4wd - with or without centre diff.. each wheel gets its independent power and the vehicle will cross the terrain more effectively!!

Quote:
Originally Posted by rrnsss View Post
If you dont get a chance to go off road , just drive in a straight stretch for 60 - 90 seconds , in 4x4 and then pull over, put it in 4 Low and drive for 10 meters or so , and then move to 2H and drive normaly.

I do this even with my manual transfer case, to make sure the gear dogs dont get rusted etc. Usualy during sunday morning 7.30 AM , when the traffic is less
Great minds think alike rrnsss!!

Last edited by Samurai : 22nd January 2008 at 15:24. Reason: Please use multi-quote feature
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Old 8th February 2008, 22:53   #56
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Hi Guys!

I just read all the thread, I'd like to say my opinion.
All I'm talking is about experience on Tata Safari/Pick-up 4x4 sold here in Italy.
About suspension, all safari have coil springs on rear axle wich is a Dana 44, early model without limited slip. Front are indipendent with torsion bars and differential is Dana 30 without Limited slip!
Pick-up has the leaf spring instead of coils and never fitted with LSD.
About use on high steep pavemented roads, towing etc. here is a trick to use 4L without destroing your drive train. Change your automatic free wheel hubs. Originals are also very weak. Put some manual locking hubs. When you engage the 4L and hubs are unlock, you will have the transfer case driveing the front differential but the power is not transfered to wheels hence you have low gears for the heavy use. Then if you go offroad you can easily lock and engage 4x4 any time you want, it is there and you do not have to warry of the delay of the automatic hubs lock. Also if you are in trouble the auto hubs they can be dangerous(reversing in mountain with bed road and low grip)!
BTW, manual hubs for Safari are available also as Nissan GR, they're exactly the same!!!
Quote:
Answer - B

with lockable differential.

Quote:
Originally Posted by Torque-ative
So which is more capable off the road .

A) A 4wd with front and rear diff. only
B) A 4wd with front, rear and central diff.

Pardon if obvious,..still wanted to know from the experts !!
I disagree, most of the full time 4x4 e.g. LR Defender, Mercedes G, have the central differential lock to be used offroad. That is because if you are for instance in the mud, and 1 wheel loose adherence with the ground, without central differential lock, all the torque will be transfered immediately to the free wheel and you get stuck! Offroad wise they are exactly the same. The difference is on pavemented roads, with unlock central differential you can drive always 4x4 and face bad road conditions(heavy rain, mud etc.). Despite this great option your fuel consumption will increase very much as you can never drive 2wd even if the road is a billiards!
Other SUV wich are not exactly offroads (honda hrw 4wd, audi allroad and such) they have drive train normally connected to front axle, if that loose grip with the road, transfer case send torque to the rear axle through a visco clutch that is engaged when the difference in revolutions between front and rear is high. Oil get warmed by friction, density increase and the power goes to rear shaft.
Hope to have been clear! Forgive my English mistake!

Best to All!!!
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Old 9th February 2008, 09:29   #57
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Thanks for the info Ignazio. Good to see another Safari enthusiast here. I always wondered about the hubs. what exactly do you mean by weak?
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Old 9th February 2008, 18:35   #58
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Default Safari Hubs

Hi all,
Quote:
jyobeb wrote
Thanks for the info Ignazio. Good to see another Safari enthusiast here. I always wondered about the hubs. what exactly do you mean by weak?
I mean that sometimes they can break when they are subject to high stress and quick lock-unlock session, particulary when used in automatic mode.
Unfortunately those conditions normally liaise with dangerous situation for people and vehicles.
That is why I changed mine, to avoid any possible risk in offroad situation!
Regards!

Ignazio
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Old 29th March 2008, 21:26   #59
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Real time AWD vehicles have slip-differential system which engages and transfers power to that wheel which looses traction. Otherwise it is on 2WD mode.

Quote:
Originally Posted by CrAzY dRiVeR View Post
What about vehicles with real-time AWD? Any special mechanism to prevent differential damage?
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Old 16th April 2008, 09:07   #60
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Default 3 diffs vs.2

3(front, rear, center) is better than 2(just front and rear)if you do get stuck in slimy deep mud. locking the center diff. affords you better traction rather than transferring power from front to rear or vice-versa. I have used all 3 diff locks on my Landcruiser to extricate myself a few times.
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