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Old 21st November 2007, 16:06   #1
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Default Question about safari Limited Slip Diffrential (LSD)

Tata safari specifications say that it has a limited slip differential. However, it stops shy of any further details.
For example what is the tolerance. Is it speed sensitive. What sort of clutch is used.
Is it front back or side only. For example if in 4x4 more both front wheels are in air, or both wheels of one side are in air, or diagonally opposite wheels are in air.
In case of 4x4, is the rear differential limited slip?

Since its a limited slip differential, and not a locking differential, I presume it can be used on tarmac(twisty conditions).

Any more information about the specifications of the same would be good.
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Old 12th December 2007, 04:40   #2
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I suggest that you visit the following URL. it might solve your query.

Limited slip differential - Wikipedia, the free encyclopedia
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Old 12th December 2007, 10:50   #3
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Quote:
Originally Posted by shaheenazk View Post
I suggest that you visit the following URL. it might solve your query.

Limited slip differential - Wikipedia, the free encyclopedia
How will that link solve my query??
That link does not have any information about the specific Limited Slip Diff used in the safari
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Old 12th December 2007, 11:01   #4
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Quote:
Originally Posted by tsk1979 View Post
How will that link solve my query??
That link does not have any information about the specific Limited Slip Diff used in the safari
Tsk, I suggest you PM Desertfox who (I think) will be able to explain this to you in detail

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Originally Posted by tsk1979 View Post
In case of 4x4, is the rear differential limited slip?
IINM, the lsd is in the context of 4x4 only?

Quote:
Originally Posted by tsk1979 View Post
Since its a limited slip differential, and not a locking differential, I presume it can be used on tarmac(twisty conditions).
I presume your question is in the context of 4H/4L? Well, it is NOT recommended to drive for prolonged stretches with 4H engaged as it causes wear & tear to the drivetrain & what is also called "bending"

Last edited by suman : 12th December 2007 at 11:06.
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Old 12th December 2007, 11:03   #5
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I too have a question about the Safari. In the television ad, they show the Safari leaping off. While in mid air, the front wheels are stationary while the rears are still spinning. Even if it was a 2wd version, wouldn't the front wheels continue to turn due to momentum?
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Old 12th December 2007, 11:08   #6
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Quote:
Originally Posted by Rtech View Post
I too have a question about the Safari. In the television ad, they show the Safari leaping off. While in mid air, the front wheels are stationary while the rears are still spinning. Even if it was a 2wd version, wouldn't the front wheels continue to turn due to momentum?
Robin, there was a thread on this mate - it was all about LSD, IIRC
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Old 12th December 2007, 11:18   #7
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hmmm. point me in that direction will ya!
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Old 12th December 2007, 11:29   #8
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Quote:
Originally Posted by Rtech View Post
I too have a question about the Safari. In the television ad, they show the Safari leaping off. While in mid air, the front wheels are stationary while the rears are still spinning. Even if it was a 2wd version, wouldn't the front wheels continue to turn due to momentum?
well, thats the advantage of the director shouting "CUTTTT"
so, put it in 2wd, take a run up and leap off... and then cutttt...
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Old 12th December 2007, 11:35   #9
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hmmm. point me in that direction will ya!
http://www.team-bhp.com/forum/techni...=safari+wheels (Safari 2.2 Ad - Why/how is the front wheel locked?)

@ya soivice
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Old 12th December 2007, 11:46   #10
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Tanveer, are you finally getting rid of your Indica and going in for the 2.2?
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Old 12th December 2007, 11:56   #11
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Tanveer, are you finally getting rid of your Indica and going in for the 2.2?
I am not getting rid of the indica... thats all I can say for now.
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Old 12th December 2007, 12:31   #12
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hmmmmm, so we are going to see another 4x4EX or a 4x4VX 2.2 on the forums soon
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Old 15th February 2008, 18:15   #13
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Default Limited Slip Differential in Tata Safari

Quote:
Originally Posted by tsk1979 View Post
Tata safari specifications say that it has a limited slip differential. However, it stops shy of any further details.
For example what is the tolerance. Is it speed sensitive. What sort of clutch is used.

Any more information about the specifications of the same would be good.
While searching for LSD on TATA Safari, came across this thread but some questions were never answered and the thread replies got diverted.

Again anybody in the know about what type of rear wheel LSD is there in TATA Safari 4wd

And Whether a retrofit can be done in a Tata Safari 2wd, i.e., converting the 2wd open differential to a 2wd LSD.

Last edited by adc : 15th February 2008 at 18:21.
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Old 15th February 2008, 22:28   #14
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From the static wheels in the ad, it appears that the LSD is in the front only. It is to help clawing up, in case even engaging the front axle does not provide enough grip. But 4x4 experts may help.

Would suggest moving this to the 4X4 section to maybe have this attract their attention.
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Old 15th February 2008, 23:24   #15
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Default Safari drivetrain

Hi all
lets see if I can clarify a bit the Safari drivetrain...
The Safari SUV 4x4 is a part time 4wd, thus there is a switch that control the traction through a transfer case.
In 2H torque is transfered only to the rear axle.
In 4H torque is transfered to front and rear axles in equal mode, as there is no a differential, 50% front 50% rear, the ratio is the same as per gear box.
In 4L torque is transfered to front and rear axles in equal mode, as there is no a differential, 50% front 50% rear, the ratio is lower as the transfer case reduce the ratio, hence 4wd low.
The only limited slip differential is in the rear, is just set to a rate of 30-40% and it works through a set of clutches and a special oil. When the difference of rotation between the two axle semi shaft is fery high (e.g. one wheel on good grip position the other in very poor grip or lifted from ground) the oil start heating, density is reduced and the clutch discs, between planetary, sticks toghether. Is not a solid stick, but enough to give some torque to the wheel in good grip position and then moving the vehicle.
Some off road situations now:
_Twist - one wheel per axle in the air in opposite direction - the Safari will have one front wheel spinning in the air and not transferring any torque to the other; one rear wheel in the air but because LSD (not the drug
is transfering some torque to the wheel with grip, the car will probably been moved forward.
_2 wheels same side up in the air - see above.
_front wheels free in the air - basically same situation of the twist, no traction from the front axle, then rear will push.
_rear wheels free in the air or both slipping - car will go only if a certain amount of grip is provided by both wheels of the front axle. If any of the 2 loose traction, well, you are stucked!

Quote:
Originally Posted by tsk1979 View Post
Tata safari specifications say that it has a limited slip differential. However, it stops shy of any further details.
For example what is the tolerance. Is it speed sensitive. What sort of clutch is used.
Is it front back or side only. For example if in 4x4 more both front wheels are in air, or both wheels of one side are in air, or diagonally opposite wheels are in air.
In case of 4x4, is the rear differential limited slip?

Since its a limited slip differential, and not a locking differential, I presume it can be used on tarmac(twisty conditions).

Any more information about the specifications of the same would be good.
Rear differential in Safari is always LSD, doesn't really matter if you are 2H, 4H or 4L.
It works on wheel speed difference, it is embedded, you can not disengage the clutches.
A different story is drive in 4wd on good grip road. NEVER TO BE DONE WITH SAFARI!!!
The reason is very simple: when the car is moving and negotiating a turn, the 4 wheels are spinning at 4 different speeds. The difference between inner and outer wheels are compensated by the differential, either front or rear axle. But we do not have a central differential in the transfer case, so we do not have compensation in speed difference between the front and the rear axles. If the "road" is low grip, the compensation is done by a certain amount of wheel spinning and everything is fine; if you are on asphalt, the compensation is not doable by the wheel, then all the drivetrain is undergoing to an extra torsion, thus breakedown (u joints, ring, pinion, shaft... the looser break...)



Quote:
Originally Posted by adc View Post

And Whether a retrofit can be done in a Tata Safari 2wd, i.e., converting the 2wd open differential to a 2wd LSD.
Can be easily done, you can use a 4wd rear axle, or you can use planetary with clutches from the original, and last but not least you can use aftermarket LSD.

I hope haven't been too boring with this long reply... Feel freee to correct me if I'm wrong somewhere.
Ciao ciao

Ignazio
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