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Old 19th February 2012, 09:25   #151
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Default Re: Driving all four wheels: how is it done?

Vishnu: IF a vehicle has Locked Rear, Locked Front or LSD front, OR Locked Front, LSD rear - Chances of it getting stuck are remote.

Also, Steering inputs make a difference in traversing the terrain, be it, ICE, SNOW, SAND, SLUSH or road!!

Beyond the above, the suspension setting of a vehicle have a role play in the dynamics too!
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Old 19th February 2012, 09:49   #152
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by jaysmokesleaves View Post
The Safari 4x4 LSD is honestly not worth a fig for serious offroad activity.
I believe the Safari 4x4 comes with a Dana 44 LSD at the rear.
If your Safari has Dana 44 diff you can install the PowerTrax in the rear. Please ensure that you can you get the right axle spline count and the diff ratio. The LSDs/Lockers are different for different axle ratios.

Quote:
Originally Posted by jaysmokesleaves View Post
Can someone explain or advise if this will be better than the existing LSD ?
I do not have specifications of the front diff.. Can an LSD be fitted in the front differential too?
Does anyone have specifications for the front Differential of the Safari 2.2 ?
Safari uses Dana 30 front axles. They will not take the load of a locker. See if you can find and LSD for it.
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Old 19th February 2012, 20:10   #153
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Default Re: Driving all four wheels: how is it done?

Im thinking of getting lockers for the rear as well after I get some 32" MT tyres. Saw the Powertrax website and they have lockers for the Ford 9 axle. Only problem is I dont know what the axle spline count is. It is either 31 or 28. I doubt anyone will know in a Ford Dealership.

Also, including shipping to India, the price comes to only around 330 US Dollars, which is a lot cheaper than I was expecting. Is this a good way to order or is there a dealer in India? Thank you for the help.

Website: Lockright (Lock Right) lockers, Powertrax, best prices, lowest cost locker kits
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Old 20th February 2012, 08:12   #154
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Default Re: Driving all four wheels: how is it done?

@Vish:

List your plans of Modifications that you think will make the endy a great OTR machine..Take it easy in little steps.

Have seen many people get all the goodies and yet get stuck in a OTR - They get frustrated!!
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Old 20th February 2012, 17:39   #155
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by headers View Post
@Vish:

List your plans of Modifications that you think will make the endy a great OTR machine..Take it easy in little steps.
In the order that I have planned in my head: First priority is to improve RAMP ANGLE as this has proven to be the weak point so far.

1) 32" MT Tyres (32x11.5x15s with Negative offset Rims. Dont care much about CL move. Im guessing it will last with a -30mm offset for about 20,000 kms before needing something replaced. I can live with that)

2) Rear Powertrax Locker (Order online or available locally? Price locally vs online?)

3) Snorkel (From Ironman 4x4. Cheaper varieties available?)

4) Steel Rear bumper with attached Tow Hook (Swastik Viji)

5) Rock sliders and Front Bullbar (Swastik Viji)

Thanks for the help
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Old 28th February 2012, 12:27   #156
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Sutripta View Post
I see no mechanism for external control of the clutch pack.
So need to know more of the MM system.
Hi Sutripta,

In XUV M&M is using electromagnetic clutch plates, which gets engaged base on the inputs received from ABS, ESP etc & controlled by ECU. When ECU senses the slippage in front wheel, then ECU send some sort of signal to electromagnetic clutch plates to get engage. This is the latest Interactive torque management system (ITM2 or ITM3) provided by BorgWarner. Given below is the screenshot of manual. I hope I am not violating any copyright by putting the screenshots as this is to understand the manual better.

Name:  AWD lock.JPG
Views: 845
Size:  86.0 KB

Hi Arka,

I am really not able to figure out how much torque will be transferred to rear axel based on the transfer case gear ratios. It will be great help if you can explain the below table in simple language. I want to know whether it is 30% or 50% torque transfer to rear axel when AWD is locked.

Driving all four wheels: how is it done?-axle-ratio.jpg

Thanks & regards

Last edited by Crazy4Power : 28th February 2012 at 12:32. Reason: attachment was not visible
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Old 28th February 2012, 22:07   #157
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Default Re: Driving all four wheels: how is it done?

^^^
Hi,
Thanks. That helps. But the number of questions only increases.

The fact that the vehicle can operate on tarmac in AWD mode means that the clutch can slip for extended periods without damage. Would like to know how that is done.

The gear ratios will not give you torque split values. In this case it will depend on the clutch pack. Because on cursory inspection (ie eyeballing pictures of the AutoExpo MM XUV cutaways) the GB seems to be doing a 50: 50 front/ rear split, if clutch is locked.

Regards
Sutripta


Next - the Tata Aria system. I feel same system from same vendor (BW). Might be (horribly) wrong though. And in the same vein, can someone educate us on the Norma crown wheel diff system. (Something more than the animations)

Regards
Sutripta
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Old 30th March 2012, 08:03   #158
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Default

Quote:
Originally Posted by Sutripta
^^^
Hi,
Thanks. That helps. But the number of questions only increases.

The fact that the vehicle can operate on tarmac in AWD mode means that the clutch can slip for extended periods without damage. Would like to know how that is done.

The gear ratios will not give you torque split values. In this case it will depend on the clutch pack. Because on cursory inspection (ie eyeballing pictures of the AutoExpo MM XUV cutaways) the GB seems to be doing a 50: 50 front/ rear split, if clutch is locked.
The clutch in a clutch based LSD is designed to slip when there is enough torque wanting to make the wheels turn at different speeds. Take the same clutch based LSD:
When you make a turn on sand, although the inside wheel is traveling a shorter distance, the clutch LSD will not let this happen because the sand does not provide the inside wheel enough traction/torque to slip the clutch. This results in both wheels traveling at the same speed.

For the same turn done on Tarmac, the inside wheel once again is traveling a shorter distance but this time the Tarmac WILL provide enough traction to the inside wheel to slip the clutch resulting in the inside wheel rotating slower than the outside wheel.

The clutch based LSD is designed to let this happen on the road. When this happens the clutch does get worn out. Hence the need to keep adjusting it. If this adjustment is not done then the clutch will slip more easily and gradually end up acting like an open diff. Adjustment is done by "shimming" the LSD, by adding friction modifiers or by using stiffer springs to press the clutch plates together. I think there are a few other ways too. Not exactly sure how the shimming is done though.
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Old 30th March 2012, 10:16   #159
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Endeavour333 View Post
...the clutch does get worn out. Hence the need to keep adjusting it. If this adjustment is not done then the clutch will slip more easily and gradually end up acting like an open diff. Adjustment is done by "shimming" the LSD, by adding friction modifiers or by using stiffer springs to press the clutch plates together. I think there are a few other ways too. Not exactly sure how the shimming is done though.
Is the need to adjust the LSD clutch pack a routine service need?

Is this done regularly / routinely on all LSDs? For e.g. the Safari has LSD, do users report that their LSDs are checked and adjusted after a certain interval?

And how much should this interval be in general?
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Old 30th March 2012, 18:00   #160
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Crazy4Power View Post
How does the FD ratio change from 4.05 to 3.115 ?
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Old 30th March 2012, 18:58   #161
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Default Re: Driving all four wheels: how is it done?

this thread covers all that I always wanted to know but was hesitant to ask about 4X4. Great thread!
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Old 30th March 2012, 20:26   #162
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Sutripta View Post
^^^
Hi,
Thanks. That helps. But the number of questions only increases.

The fact that the vehicle can operate on tarmac in AWD mode means that the clutch can slip for extended periods without damage. Would like to know how that is done.
Sutripta: This system is never meant to be used like a Full Time AWD System from a Toyota Landcruiser or Mitsubishi Pajero. It is only for temporary usage when there is slippage. When you put it in AWD Lock, it will automatically disengage once you reach a certain speed. Otherwise the clutch will burn out.

To run in permanent 4x4 you need a center differential like in Pajero/Landruiser/Fortuner etc...
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Old 30th March 2012, 21:25   #163
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Endeavour333 View Post
The clutch in a clutch based LSD is designed to slip when there is enough torque wanting to make the wheels turn at different speeds.
....

The clutch based LSD is designed to let this happen on the road.
Discussion/ question was wrt the system in the XUV. Clutch with no (central) diff.

Quote:
Originally Posted by 4x4addict View Post
Sutripta: This system is never meant to be used like a Full Time AWD System from a Toyota Landcruiser or Mitsubishi Pajero. It is only for temporary usage when there is slippage. When you put it in AWD Lock, it will automatically disengage once you reach a certain speed. Otherwise the clutch will burn out.
Well, their literature (scanned and posted by crazy4power) says you can use it in lock mode on tarmac. With no qualifiers.

Regards
Sutripta
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Old 31st March 2012, 17:28   #164
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Default Re: Driving all four wheels: how is it done?

Quote:
Originally Posted by Sutripta View Post
Well, their literature (scanned and posted by crazy4power) says you can use it in lock mode on tarmac. With no qualifiers.
I didn't say that it cannot be engaged on Tarmac. What I said was that it will automatically disengage beyond a certain speed regardless of the terrain.

You can lock in on Tarmac and there is no problem. It will disengage beyond a certain speed. In the Honda CRV/Pilot etc, it is beyond 16 mph.
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Old 19th April 2012, 12:39   #165
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Exclamation Re: Driving all four wheels: how is it done?

here are two links for two different vehicle's Service manuals that I have found during my study .

One can check & compare these two ( wrt transmission Systemes ) with the existing Jeep / Gypsy things we know

1 The M 151

library m151 publication maintenance manual tm-2320-218 tm 9-2320-251


2 The Hummer ( HMMWV ) check the geared hubs - its interesting

http://www.team-bhp.com/forum/4x4-te...inks-info.html (Military HMMWV (Humvee ) Manuals -Links & Info)

Sudarshan
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