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Old 28th February 2009, 22:54   #46
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I think it's more fun trying 4H to the maximum and engage 4L only when it's really required.Also, when you use 4L-3rd or 4L-4th you will hear more drivetrain sound than when you are in 4H-Ist or 4H-2nd.Anyways, i will be watching this thread closely for making any adjustments to my driving.But it's always less involving and easy to drive the whole terrain in 4L and move up & down through the gears.This is with respect to MM540 and for our old jeep (international engine) will need 4L even at the sight of an incline.
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Old 28th February 2009, 23:29   #47
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Quote:
Originally Posted by Tusker4x4 View Post
We are essentially a Jeep lovers group but now with the new members joining in we have started to experience Gypsys.
Sorry to be so ignorant but who is this "We are essentially a Jeep lovers group"?
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Old 28th February 2009, 23:43   #48
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Originally Posted by hrag View Post
Sorry to be so ignorant but who is this "We are essentially a Jeep lovers group"?

NIOC - Nothern India Offroad Club

Amit
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Old 1st March 2009, 09:04   #49
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Quote:
Originally Posted by susan3004 View Post
Mr Dhabar may like to correct me if I am wrong but the front suspension also feels less responsive when on tarmac in 4H mode.
It the steering feedback that gives you the feel of a less responsive suspension!

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Originally Posted by Tusker4x4 View Post
Even when i got stuck he got guys to pull me out so that I dont have fear of getting stuck.
Amit, this is hilarious, why did you not use 4wd to get out when you got stuck?

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Originally Posted by jack33 View Post
I think it's more fun trying 4H to the maximum and engage 4L only when it's really required.Also, when you use 4L-3rd or 4L-4th you will hear more drivetrain sound than when you are in 4H-Ist or 4H-2nd.

..
But it's always less involving and easy to drive the whole terrain in 4L and move up & down through the gears.This is with respect to MM540 and for our old jeep (international engine) will need 4L even at the sight of an incline.
A +1 to that sir!

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"We are essentially a Jeep lovers group"?

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Originally Posted by Tusker4x4 View Post
NIOC - Nothern India Offroad Club

This is an offshoot of Jeepthrills, and both co-exist now!
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Old 1st March 2009, 09:48   #50
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Originally Posted by desertfox View Post
DRIVING IN 4WD

There is a lot of myth and misunderstandings that go with the Indian aversion to driving in 4WD i.e. with the 4x4 drive system engaged.

Why shouldn't you drive in 4WD when your vehicle has a 4 WD system in it, it is there for you to negotiate tricky terrain, but the general syndrome is it is some kind of a monster, you must disengage as soon as an obtacle like some soft sand or a mud pool has been crossed.
Well said, Shahid and welcome to Team BHP - I didnt notice you were here as 'desert fox'. For those who didnt know, shahid was the founder of the Dubai Desert Club, which then became Emarat4x4.

My personal experiences - I use 4H when I go off the tarmac into loose trails. It helps keep the vehicle in line and steering is much more predictable.

4L is something I use on the Safari quite sparingly because it seems to be rather low - the vehicle really crawls in 4L even on 3/4th gear, so I'd prefer to do slightly tougher sections on 4H 1/2 gear and shift to 4L only where required - this is in slush or rocky terrain.

On my Defender, however, I find myself using 4L more often. Probably because the terrain is sand most of the time (its the reverse on Wadi/rock where we use 4H mostly and shift to 4L only on sections that require some climbing).

DB said here that 4H 1 is the rough equivalent of 4L 3 and that is true.

Perhaps it is better to leave the vehicle on 4H and shift to 4L occassionally if the trail is such that so much engine torque will not be required as much as traction.

Where engine torque is required to climb over steep slopes or crawl through slushy mud most of the time 4L on most of the time may be a better idea.

At the end of the day, a 4x4 is meant to be used as a 4x4 - I would disagree on the point that using 4x4 taxes the engine. The vehicle is built to take the punishment and therefore it is only serving the purpose it was meant to.
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Old 1st March 2009, 16:46   #51
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Quote:
Originally Posted by headers View Post
Amit, this is hilarious, why did you not use 4wd to get out when you got stuck?
This is an offshoot of Jeepthrills, and both co-exist now!
Dear Headers,

I wass just once so that the fear of getting pulled out goes.

You are very correct it is an offshoot of Jeep Thrills and its best to co-exist as they both have very experienced offroaders and very releveant discussions on the forums.

Regds

Amit
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Old 3rd March 2009, 13:39   #52
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Default 4H -- Additional Reduction

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Originally Posted by khan_sultan View Post
A VERY important. Infact, even clubbing a Gypsy/MM together may also not be right. Essentially, what works for one 4x4 may not work for another 4x4.

For example, IIRC, a MM's 4H ratio does NOT do any reduction/torque multiplication (please confirm or rectify ) where as in a Gypsy the 4H does a reduction/t-m of 1.409:1

This aspect also would change the equation of using 4H or 4L in various conditions & various vehicles -- depending on how the ratios are setup.

I doubt if the reduction changes from 2H to 4H.

In a Gypsy the Differential Ratio is 3.7:1 where as M&M Series are 4.27:1/4.88:1/5.38:1

The overall crawl Ratios are similar, the M&M's have a lower crawl ratio.

The Lower High Range is to compensate for Higher Differential Ratio.

In all T-Cases 4H engages the Front Propeller Shaft.

the 2H Crawl Ratio will be 1st Gear X T-Case Ratio X Diff-Ratio.

A additional reduction will complicate the T-Case effectively making it 3 Speed.

Regards,

Arka
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Old 3rd March 2009, 15:29   #53
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Did anybody use 4H most of the time in Savanadurga OTR in Bangalore? I couldn't.

I was driving a SWB Jeep with 4.27:1 axle ratio with heavily oversized tyre bringing the effective ratio to 3.85:1 approximately. Therefore, there was no question of using 4H, for me 4L itself was quite fast. In fact it was difficult to crawl in 1st low, it was closer to 2nd low in my Jeep.
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Old 3rd March 2009, 16:37   #54
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Quote:
Originally Posted by Samurai View Post
Did anybody use 4H most of the time in Savanadurga OTR in Bangalore? I couldn't.

I was driving a SWB Jeep with 4.27:1 axle ratio with heavily oversized tyre bringing the effective ratio to 3.85:1 approximately. Therefore, there was no question of using 4H, for me 4L itself was quite fast. In fact it was difficult to crawl in 1st low, it was closer to 2nd low in my Jeep.
No -- I don't remember using 4H this time around extensively.

2WD while coming down the dirt track and going up (from the turn till the river)
Mostly it was 4L 1,2,3 depending on terrain.

Last edited by khan_sultan : 3rd March 2009 at 16:39.
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Old 4th March 2009, 12:36   #55
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Very interesting topic this.As far as I'm concerned,I TRY 4L,4H in all gears just to get to understand the capabalities of my vehicle & have some fun, but that's as far as OTRs are concerned,where it is a group event & I know for sure that I'll be pulled out.When I'm alone & know that there is no help around,I just stick to 4L & change between 2nd 3rd & 4th.So,IMO OTRs are fun, offroading is serious.
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Old 21st June 2010, 07:40   #56
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Bumping this thread to clarify a doubt:

In reading through this thread...

For the CJ3Bs with only 3 forward gears, would 3 L be roughly equivalent to 3L + 4L in the 550's?
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Old 21st June 2010, 08:12   #57
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Quote:
Originally Posted by genesis View Post
Bumping this thread to clarify a doubt:

In reading through this thread...

For the CJ3Bs with only 3 forward gears, would 3 L be roughly equivalent to 3L + 4L in the 550's?
Yes, the GB ratios are different. In certain situations they are more versatile as well.
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Old 21st June 2010, 09:33   #58
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Dear all - this is a very nice thread, although I have only read the last page.

As soon as I leave tarmac, I am in 4WD. As most of the time as I am in convoy in the MGE (although I am "officially" allowed to overtake and I have to overtake, sometimes with inches to spare from other cars and sometimes going through things unimaginable, to reach the "VVVIP"s who inadvertently get stuck, it used to be my job to tow them out), I am in low range and I start moving in third gear, shift to foutrh and keep on driving. You can very comfortably drive the CL340 in fourth low at 40 kmph off road. You can go faster also, but it needs intense control. This gives me the advantage of being able to use low third or low second as the situation demands. Everybody knows that the CL340 is the undisputed king of this type of terrain and this type of transmission "ratio selective" driving. That's the beauty of the CL340, isn't it guys?.

Best regards,

Behram Dhabhar
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Old 21st June 2010, 09:47   #59
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Quote:
Originally Posted by DHABHAR.BEHRAM View Post
Dear all - this is a very nice thread, although I have only read the last page.

As soon as I leave tarmac, I am in 4WD. As most of the time as I am in convoy in the MGE (although I am "officially" allowed to overtake and I have to overtake, sometimes with inches to spare from other cars and sometimes going through things unimaginable, to reach the "VVVIP"s who inadvertently get stuck, it used to be my job to tow them out), I am in low range and I start moving in third gear, shift to foutrh and keep on driving. You can very comfortably drive the CL340 in fourth low at 40 kmph off road. You can go faster also, but it needs intense control. This gives me the advantage of being able to use low third or low second as the situation demands. Everybody knows that the CL340 is the undisputed king of this type of terrain and this type of transmission "ratio selective" driving. That's the beauty of the CL340, isn't it guys?.

Best regards,

Behram Dhabhar
@headers: Thanks!

@Behram: Does this mean that for a CJ3B with 3 gears, it is "technically" okay to be driving on 3L most of the time off tarmac without messing up the diffs and other assorted mechanisms. Asking this since I wont be able to move to 4 L
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Old 21st June 2010, 09:55   #60
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[quote=genesis;1945936
@Behram: Does this mean that for a CJ3B with 3 gears, it is "technically" okay to be driving on 3L most of the time off tarmac without messing up the diffs and other assorted mechanisms. Asking this since I wont be able to move to 4 L [/quote]

The gear ratio's of 3rd gear in a 3B is same as 4th gear on a 4 speed gear box which is 1:1. Hence you move into low ratio as soon as you hit off road and if the terrain is not severe then drive all day long in 3rd low.
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