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Old 15th February 2008, 23:45   #16
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Default Ad Video

... forget to say, I think that Ad video is a fake, have you never try to lift your car on a mechanic bridge? your wheels will go immediately at the maximum extension of the spring/shock absorber system. In the video the wheels are at the same height of the regular drive on the road....

cheers:

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Old 16th February 2008, 00:06   #17
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Originally Posted by Ignazio View Post
Hi all

lets see if I can clarify a bit the Safari drivetrain...

Ignazio

Thanks a lot, great reading the post. It does clear all the queries.


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Originally Posted by Ignazio View Post
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.

Please do correct me and do put in your comments on these three remarks:

1. For a 2wd Safari, the easiest and cheapest would be the aftermarket LSD unit rather than the whole axle.

2. A 2wd LSD should pull out through in most mud and snow situations under controlled acceleration.

3. Hard acceleration of 2wd LSD in slippery conditions will spin the vehicle.

Last edited by adc : 16th February 2008 at 00:12.
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Old 16th February 2008, 00:56   #18
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Hi!
Quote:
Originally Posted by adc View Post
Thanks a lot, great reading the post. It does clear all the queries.


A pleasure mate! My answers in Bold...

1. For a 2wd Safari, the easiest and cheapest would be the aftermarket LSD unit rather than the whole axle.
YES! (it depends also on how much will be the original Tata spare)Have a look here, search for Dana 44:Randy's Ring & Pinion.

2. A 2wd LSD should pull out through in most mud and snow situations under controlled acceleration.
YES! Indeed!

3. Hard acceleration of 2wd LSD in slippery conditions will spin the vehicle.
YES! Indeed!
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Old 16th February 2008, 01:58   #19
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2. A 2wd LSD should pull out through in most mud and snow situations under controlled acceleration.
Not necessarily. LSD would only be of use if one of the two wheels have grip. If both dont, it is useless, thats when the prospect of finding grip on the other axle increases the chances of pulling up.

Lot lot many days back. We were returning from a steel plant construction site in Nigeria with my father. It had rained very heavily prior to that and the road connecting the site to the township was all muddy. Our trusted vehicle was a Nissan Patrol SWB. Dad had already slipped the beast in 4WD mode and was still progressing with the thing fishtailing all the way requiring constant correction (later I learnt it was a usual routine during rainy season) but very predictable.

2 kms down the road (8 more to go), we saw one of his colleagues (an uncle) who was new to the setup, being stuck in his LWB Patrol. Incidentally that Patrol was not recommended to be taken to the site, as the front axles did not engage on it, but as there was no sign of rain in the morning, a calculated risk was taken by him.

He had actually done the mistake of high revving the wheels.

Initially a lot of efforts were given by my Dad to make it move, it did but was a uncontrollable quantity, needing constant steering swaying to free up the front, moreover the rear was actually drifting in every direction, even with a very slow movement of the wheel.

All this time, the SWB (which was engaged in 4WD low) one was happily going forward backward as they wanted it to go (with a little bit of side slipping). A towing attempt was tried, initially but in that case the SWB was actually moving sideways. Later both of these were fired up, and the towing SWB was used as a guide/steering car to keep the Powered LWB on track.

Now all this time the tyre tracks were just about 2 inches deep.

Last edited by 1100D : 16th February 2008 at 02:10.
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Old 16th February 2008, 14:00   #20
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Default DANA 44 - Limited Slip Differentials

Hi Guys,
The Tata 4WDs, M&M MM550XD & HM RTV use Dana 44s with 19-22 Splines.
However the clutch mechanism for the LSD is similar, i.e Plate Clutch.

Regards,

Arka
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Old 16th February 2008, 14:55   #21
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Hi all!
Quote:
Originally Posted by ex670c View Post
Hi Guys,
The Tata 4WDs, M&M MM550XD & HM RTV use Dana 44s with 19-22 Splines.
However the clutch mechanism for the LSD is similar, i.e Plate Clutch.

Regards,

Arka
AFAIK the Tatas 44's are 30 splines...

Ciao

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Old 17th February 2008, 01:02   #22
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Not necessarily. LSD would only be of use if one of the two wheels have grip. If both dont, it is useless, thats when the prospect of finding grip on the other axle increases the chances of pulling up.

Now all this time the tyre tracks were just about 2 inches deep.

LSD puts power to the wheel thats not spinning, locking hubs put power to both wheels equally. As seen in the above example, 2 rear tyres in slippery mud of a 2wd with LSD is worse than an normal 2wd, i.e, open differential. It will just spin itself to may be a dangerous position.

Thus the best option for a 2wd, to come close to a 4wd, where both tyres are on slippery mud, a locking rear hub - like the ARB Air Locker though expensive. Powertrax Noslip is another interesting product that I saw on the net.

Do correct if my observations are wrong.
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Old 17th February 2008, 09:42   #23
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Originally Posted by adc View Post
LSD puts power to the wheel thats not spinning
It depends, if the LSD is torque sensing type, then if one wheel is completely free, then no power transfer takes place. In such case you are better off with viscous coupling or clutch type I think.
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Old 17th February 2008, 14:03   #24
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Forza Italia!

Congratulations Ignazio for this detailed, precise and accurate explanation. I got a similar one (not as good by the way) from a Mahindra Scorpio (Goa) salesperson regarding the LSD on their pick-up.

Batla (from France)
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Old 17th February 2008, 19:10   #25
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Hi all,
Quote:
Originally Posted by adc View Post
LSD puts power to the wheel thats not spinning, locking hubs put power to both wheels equally. As seen in the above example, 2 rear tyres in slippery mud of a 2wd with LSD is worse than an normal 2wd, i.e, open differential. It will just spin itself to may be a dangerous position.

Thus the best option for a 2wd, to come close to a 4wd, where both tyres are on slippery mud, a locking rear hub - like the ARB Air Locker though expensive. Powertrax Noslip is another interesting product that I saw on the net.

Do correct if my observations are wrong.
Why should open be better than LSD?
If your axle is on a poor surface and your wheels are not having a proper grip, with an open differntial you must have grip on both to get traction. If you have an LSD than the first grip available on any of the two wheels is used to push the car. The trust will never be same as the full locking differential, but already enough to get off the mud.
Full lock is a different story, but you have to engage it manually and can it be too late in certain situation...
Have a look for a product called ECTED...

Ciao!

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Old 17th February 2008, 21:47   #26
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Very true indeed! But inspite of all the LSD, amphetamines and vitamins, the Safari/Scorpio will not take you where a Gypsy or a MM would...hehehe - watsay folks?
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Old 17th February 2008, 23:02   #27
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Hi,

Quote:
Originally Posted by diff_locked View Post
Very true indeed! But inspite of all the LSD, amphetamines and vitamins, the Safari/Scorpio will not take you where a Gypsy or a MM would...hehehe - watsay folks?
have a look at this...........Spanish friends.........



Ciao!

Ignazio
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Old 17th February 2008, 23:11   #28
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have a look at this...........Spanish friends.........
Tell 'em Ignazio. You will be surprised that in the land of your Elefant, it isnt considered 'good enough' to go offroad.

But then again, if you really know us you wouldnt be surprised.
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Old 18th February 2008, 00:18   #29
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Wow! The second video is amazing. The safari had one wheel in air, and two stuck in muck.
But I guess the Tatateam videos show modded safaris? Or are they stock with additional underbody protection.
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Old 18th February 2008, 02:11   #30
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Quote:
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Why should open be better than LSD?
If your axle is on a poor surface and your wheels are not having a proper grip, with an open differntial you must have grip on both to get traction. If you have an LSD than the first grip available on any of the two wheels is used to push the car. The trust will never be same as the full locking differential, but already enough to get off the mud.
Full lock is a different story, but you have to engage it manually and can it be too late in certain situation...
Thanks for correcting me, I was assuming a situation [2wd rear wheel LSD] in slippery mud whereby only one wheel always gets the majority of traction due to slippage of the other tyre and thus the car spins around or where two wheels loose traction due to a patch of very slippery mud and the LSD becomes useless. However in real life situation this is not so and one of both rear car tyres are having traction at any point in time or simultaneously, and then will be able to get out from the stuck situation.

It seems then with LSD and mud track, car acceleration pays a very vital role. As you had clarified earlier a hard accleration [again relative to what kind of mud it is] will spin the vehicle. On that basis then 2wd Safari with Rear wheel LSD will also be trickier to manage during a downhill mud track situation, i.e, a downsloping slippery track.


Quote:
Originally Posted by Ignazio View Post
Have a look for a product called ECTED...
Looks like the Eaton Elocker is the most suitable for highway purpose as well as for moderate offroad. It maintains an open differential [not default LSD] in highway runs and locks otherwise when needed by a simple switch operation.


Again a whole lot of thanks for your detailed replies to all the questions and observations. All these knowledge is more than enough for me now, will bother you up again if and ever I think about converting the 2wd Safari LX to a 2wd Safari LX LSD or Rear Locker!!!

Last edited by adc : 18th February 2008 at 02:16.
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