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Old 16th April 2008, 10:54   #61
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You not only have 3 diffs, but also have 3 diff locks. That makes a huge difference when you are stuck. Mine has 3 diffs, but only 1 diff lock (central). The front and rear open differentials can be a problem if one of the wheels lose traction, as I experienced lately.
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Old 16th April 2008, 11:06   #62
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The front and rear open differentials can be a problem if one of the wheels lose traction, as I experienced lately.
Couldn't quite understand this.
One wheel loses traction: how does this represent a problem?
Can you elaborate please?
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Old 16th April 2008, 11:38   #63
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Originally Posted by anupmathur View Post
Couldn't quite understand this.
One wheel loses traction: how does this represent a problem?
Can you elaborate please?
I mean in each axle, I have mentioned front and rear in that sentence. One wheel spin in each axle will make my GV sitting duck. Hope this clarifies.
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Old 16th April 2008, 12:15   #64
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A safari has front and rear diff's no locks, but LSD.
Does this mean that if one wheel is in the air and is spinning freely, the other wheel on the same action will also spin(albeit at a slower speed?)
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Old 16th April 2008, 12:55   #65
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Quote:
Originally Posted by tsk1979 View Post
A safari has front and rear diff's no locks, but LSD.
Does this mean that if one wheel is in the air and is spinning freely, the other wheel on the same action will also spin(albeit at a slower speed?)
Actually it is better than having open diffs. If one wheel spins on the rear, it will force the other rear wheel to turn, therefore it won't get stuck.

But it also depends on the type of LSD. The viscous/clutch type LSD works as described above. But the torque sensitive LSD needs some torque on the spinning wheel. If one wheel is free-spinning, then there is no torque, then the other wheel has no torque either. Remember, torque is the minimum force required to make the wheel turn. In such cases, applying brakes on the spinning wheels can recover some torque.
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Old 16th April 2008, 13:45   #66
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I don't think the Safari has a torque sensitive setup, its a viscous type LSD. I think some safari 4x4 experts can elaborate.
Italian boys.. any ideas?
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Old 16th April 2008, 14:28   #67
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Originally Posted by tsk1979 View Post
I don't think the Safari has a torque sensitive setup, its a viscous type LSD. I think some safari 4x4 experts can elaborate.
Italian boys.. any ideas?
It has a clutch (ie friction) based LSD (only in 4x4) on the rear axle. It connects the two halfshafts through a slipping clutch. Its works in a manner similar to the main clutch, when partially engaged.
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Old 16th April 2008, 14:56   #68
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So front axle is open.
This means unless both rear wheels lose traction, you won't get stuck.
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Old 17th April 2008, 03:21   #69
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Hi,
as torque is splitted by transfer case to 50% front and 50% rear, if the two back wheels are spinning but the front are some how gripping to the ground you will not get stuck, front will pull you...
Safari, after 2000 TL and new Xenon, they all have cutch LSD at the back and open diff. at the front.
Mounting soon a diff lock on mine, when money permit... It's a '98, so just open diff front and rear but is climbing quite well!!!
I'll post some video soon!

Ciao

Ignazio
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Old 17th April 2008, 18:39   #70
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Quote:
Originally Posted by tsk1979 View Post
So front axle is open.
This means unless both rear wheels lose traction, you won't get stuck.
It can get stuck if one of the front and rear wheels hast lost purchase, and the other rear wheel is not being 'supplied' enought torque through the LSD to get things moving. Clutch based LSD have some 'lock' ratio, like say 30%. So the tyre with better traction will always recieve atleat 30% of maximum torque at the rear axle. Some clutch based LSDs tend to heat up quickly and degrade during heavy use.
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Old 6th June 2008, 12:44   #71
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Originally Posted by gd1418 View Post
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.
You will not damage the tranny and differential unless you drive in 4wd for a long time say 1000 kms or so on tar roads.. The gears are all hardened and tempered to without a fair amount of abuse.

Quote:
Originally Posted by Samurai View Post
You not only have 3 diffs, but also have 3 diff locks. That makes a huge difference when you are stuck. Mine has 3 diffs, but only 1 diff lock (central). The front and rear open differentials can be a problem if one of the wheels lose traction, as I experienced lately.
Quote:
Originally Posted by tsk1979 View Post
A safari has front and rear diff's no locks, but LSD.
Does this mean that if one wheel is in the air and is spinning freely, the other wheel on the same action will also spin(albeit at a slower speed?)
Quote:
Originally Posted by Samurai View Post
Actually it is better than having open diffs. If one wheel spins on the rear, it will force the other rear wheel to turn, therefore it won't get stuck.

But it also depends on the type of LSD. The viscous/clutch type LSD works as described above. But the torque sensitive LSD needs some torque on the spinning wheel. If one wheel is free-spinning, then there is no torque, then the other wheel has no torque either. Remember, torque is the minimum force required to make the wheel turn. In such cases, applying brakes on the spinning wheels can recover some torque.
This is a great technique even in 2wd when one gets stuck and both wheels are spinning. Apply brake gently until one of the wheels stop rotating and the vehicle will move forward!
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Old 6th June 2008, 13:13   #72
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Originally Posted by headers View Post
This is a great technique even in 2wd when one gets stuck and both wheels are spinning. Apply brake gently until one of the wheels stop rotating and the vehicle will move forward!
Have you done this Headers? To my understanding, this works only in vehicles with torsen type diffs or if the brakes can be selectively applied/brake bias is laterally unsymetrical.
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Old 6th June 2008, 13:21   #73
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Originally Posted by Alfa_Kilo View Post
Have you done this Headers? To my understanding, this works only in vehicles with torsen type diffs or if the brakes can be selectively applied/brake bias is laterally unsymetrical.
this will work even in the standard diff., but as headers as mentioned, it has to be done in a certain way .
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Old 6th June 2008, 13:31   #74
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Well have tried it in the indica, and it does not work. Maybe it works in RWDs with drum brakes which are not as grippy as the discs.
Or maybe I need 100 horses more.
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Old 6th June 2008, 13:54   #75
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Quote:
Originally Posted by tsk1979 View Post
Well have tried it in the indica, and it does not work. Maybe it works in RWDs with drum brakes which are not as grippy as the discs.
Or maybe I need 100 horses more.
Or maybe you need the right technique, Tanveer Sir!
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