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Old 27th January 2009, 20:03   #61
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Wicked! I know the feeling
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Old 28th January 2009, 11:38   #62
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Great to see the update. Awesome off-roading performance with on-road zipping! Whow!
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Old 14th February 2009, 21:55   #63
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Default Crawl ratio

Hi Khan_Sultan,

I have heard from Naveen and Arjun that you have installed a crawl ration in your Gypsy. Kindly enlighten on the crawl ratio. And is it maily for the Gypsy or for Jeeps also.

Regds

Amit
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Old 15th February 2009, 09:11   #64
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Quote:
Originally Posted by Tusker4x4 View Post
...I have heard from Naveen and Arjun that you have installed a crawl ration in your Gypsy. Kindly enlighten on the crawl ratio. And is it maily for the Gypsy or for Jeeps also....
Amit, It's mentioned in the opening post of this thread.

here is it again:

I have 'crawler gears' in the t-case. These have 'short gear ratios'.

Crawl ratio is the ability of a 4x4 to 'literally crawl' on a terrain. The higher this ratio the better. This ability comes handy when traversing over rocks/boulders.

Quote:
To give another perspective on what this means in off-roading & rock climbing, let me explain on what this will do to the 'crawl ratio' of my MG413W

The stock crawl ratio of MG413w is:
3.652 * 2.268 * 3.727 = 30.869

With the 4.16:1 t-case gearset, the crawl ratio would become:
3.652 * 4.160 * 3.727 = 56.621

To put this in perspective, the crawl ratio of a CL340 & CL340 Classic is:
3.986 * 2.460 * 4.880 = 47.851 (CL340 Classic)
3.986 * 2.460 * 5.380 = 52.754 (CL340 )
Now, the crawl ratio of my Gypsy is ~10% more than the CJ340 jeep & ~20% more than the CLASSIC.

So now I have the best of both world -- an amazing crawl ratio & all the advantages of a Gypsy (momentum, light weight, speed, etc..)


PS: I think that the Ultra Low Rock Crawler t-case gear sets are available for Jeeps also but not needed for the kind of terrain that we do in India. The jeeps have plenty of 'rock crawling' capabilities and the diesel low end torque helps. So no need for this in a Jeep.

In a petrol Gypsy, this mod address the low end torque issue with 'gearing'

Last edited by khan_sultan : 15th February 2009 at 09:25.
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Old 15th February 2009, 20:25   #65
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Great !!

Arjun, one of the member in NIOC just bought a new gypsy. We had a problem of reversing him back from a climb in 4x4L reverse as the engine braking did not work. Infact I think Pushkin gave you a call for this also.

So the crawl ratio is needed in gypsy. We did hear that it is there in the Army Gypsy's, is it so ?

Thanks

Amit
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Old 15th February 2009, 21:16   #66
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Hi Khan Sultan,

Just saw ur avtar (as they call it here).

So it was your Jeep on the climb in the Mini OTR thread in the Resort you guys were staying for the Munnar GE.

That was realy putting crwal ratio to test. Great going

Amit
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Old 16th February 2009, 00:12   #67
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Quote:
Originally Posted by Tusker4x4 View Post
So the crawl ratio is needed in gypsy. We did hear that it is there in the Army Gypsy's, is it so ?
Do not believe in hearsay.
Army Gypsy's are identical to civil versions in totality.
The only things extra are the rear tow plate/hook and blackout lamps.

Cheers
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Old 16th February 2009, 09:14   #68
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Quote:
Originally Posted by Tusker4x4 View Post
.... We had a problem of reversing him back from a climb in 4x4L reverse as the engine braking did not work.
Yes, there is a huge difference of engine braking in Petrol Gypsy & Diesel Jeeps. You can't compare the two.

Quote:
... So the crawl ratio is needed in gypsy.
No. not necessary. I did not have it for 2.5 years in my Gypsy and never was able to NOT do a terrain which jeeps were able to do. It required a slightly 'different' way of tacking the terrains.

Now, why I have put in the 4.16 t-case gearset is another discussion altogether.

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Do not believe in hearsay.
That should be the mantra -- for all aspects of mods also.
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Old 13th March 2009, 02:27   #69
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Quote:
Originally Posted by khan_sultan View Post
Yes, there is a huge difference of engine braking in Petrol Gypsy & Diesel Jeeps. You can't compare the two.



No. not necessary. I did not have it for 2.5 years in my Gypsy and never was able to NOT do a terrain which jeeps were able to do. It required a slightly 'different' way of tacking the terrains.

Now, why I have put in the 4.16 t-case gearset is another discussion altogether.



That should be the mantra -- for all aspects of mods also.
Khan_Sultan great goint with the T case mod. Having driven a stock 410 I know this addresses the gypsys need for crawling. A winch would greatly enhance off road capability, given the T case mod and the rear diff -lock.
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Old 23rd March 2009, 19:39   #70
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Here is an update on the t-case after this weekend's recee.

As usual the torque is just amazing and managed to do some rocky terrains with amazing ease.

However I blew 2 of my t-case beading's because of the immense torque it generated while I was trying to pull out another Gypsy that as stuck.

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The blown beading gave me lots of grief and good that I had a spare t-case beading that we managed to put in.

Good thing is, that with SPoA the GC is so much that one can just slide underneath and do the repairs (Yes, there are 2 people below the Gypsy in the picture below)

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Learning's for me:
  • Don't use the Gypsy for pulling a stuck vehicle out -- especially if there is a MM around. The t-case beadings will just blow up & also the clutch
  • Always carry spare t-case beadings -- if possible, atleast a dozen
  • Invest time & effort in finding a permanent solution for this
Cheers,
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Old 24th March 2009, 11:29   #71
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Default T-Case Beading/Beds/Gaskets

Quote:
Originally Posted by khan_sultan View Post
Here is an update on the t-case after this weekend's recee.

As usual the torque is just amazing and managed to do some rocky terrains with amazing ease.

However I blew 2 of my t-case beading's because of the immense torque it generated while I was trying to pull out another Gypsy that as stuck.

The blown beading gave me lots of grief and good that I had a spare t-case beading that we managed to put in.

Good thing is, that with SPoA the GC is so much that one can just slide underneath and do the repairs (Yes, there are 2 people below the Gypsy in the picture below)

Learning's for me:
  • Don't use the Gypsy for pulling a stuck vehicle out -- especially if there is a MM around. The t-case beadings will just blow up & also the clutch
  • Always carry spare t-case beadings -- if possible, atleast a dozen
  • Invest time & effort in finding a permanent solution for this
Cheers,
Hi Shahnawaz,

By T-Case beading do you mean the Rubber Beds on which the T-Case is mounted?.

Normally I have seen gypsy's damaging their T-Case Beds because they have not Lower or Top Cross-Member, and any impact/hit/scrap to the T-Case damages the T-Case Bed.

Have you ruled out the SPOA mod and the additional pinion angle/pinion pitch as a factor.

In case you are talking about the T-Case Gasket then check the breather plugs, they maybe blocked and are not venting the hot air, resulting in high pressure in the T-Case and Gasket Leaks/sweating.

Also the Max Torque coming out from the T-Case is

1 Gear X Low Ratio X Engine Peak Torque = 3.6 x 4.16 X 13kgm = 194kgm
Reverse X Low Ratio X Engine Peak Torque = 3.4 X 4.16 X 13kgm = 183kgm

That is not too much, and I'm sure you would have reached the same levels in every off-road after the T-Case mod.

Regards,

Arka
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Old 24th March 2009, 17:11   #72
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Now, the crawl ratio of my Gypsy is ~10% more than the CJ340 jeep & ~20% more than the CLASSIC.


Shanavaz,
You have now almost doubled the torque on the axles. Some time, open it and have a look at the drive spline's condition for any wear or twisting
suresh
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Old 24th March 2009, 18:47   #73
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when one of the t case beddings on my gypsy gave up , i couldnt find one in time so , i used a ss80 ( old m 800) gearbox bedding in its place , see if you can use those at all 3 points . they are bigger but managed to fit it .


the stock bedding is actually very small and the quality of the ones available are not that great .

we think of changing the t case bedding only after it breaks , may be we should change it as a part of preventive maintenance .

also which reminds me , you owe me one t case bedding , when you buy them by the dozen.
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Old 24th March 2009, 19:00   #74
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Quote:
Originally Posted by ex670c View Post
Hi Shahnawaz,

By T-Case beading do you mean the Rubber Beds on which the T-Case is mounted?.

....
It is the rubber beading -- 3 in nos. I broke two of them and they actually shear off due to the torque. As siddharth mentions below they are not of good quality and it is a very well known problem in modded t-case setups worldwide.

This time they sheared (I think) because while trying to pull out a gypsy. They were perfect before that.

Quote:
Originally Posted by Suresh Stephen View Post
...
You have now almost doubled the torque on the axles. Some time, open it and have a look at the drive spline's condition for any wear or twisting
suresh
Will do a check sometime. I know what you are referring to am have that on my mind

Quote:
Originally Posted by siddartha View Post
... the stock bedding is actually very small and the quality of the ones available are not that great .
yes. 100% correct.

Quote:
we think of changing the t case bedding only after it breaks , may be we should change it as a part of preventive maintenance .
I had just changed all 3 just some months ago while the t-case mod was done

Quote:
also which reminds me , you owe me one t case bedding , when you buy them by the dozen.
Yes. It was actually your spare beading that I used last week. I owe you one.
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Old 24th March 2009, 20:24   #75
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Khan, there is sometimes a big difference between N. American English and U.K. English. This may be a case. WHAT IS A BEADING exactly? It is still unclear to me.
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