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Old 16th December 2015, 10:32   #226
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Spent the last few days driving the Jeep in coastal Karnataka and quite a bit of off-road stuff in the Western ghats (Kodachadri climb).

Notes:


- Engine and transmission are top notch in terms of power delivery, if not in refinement. The low range ratio of 2.5:1 seems very adequate for the impressive amount of torque put out by the DI diesel. The 4 speed transmission is almost superfluous.This is a welcome departure for me since my experience is primarily with large gasoline engines where crawl ratios >3:1 are required for good performance.

- Steering has excessive play resulting in very poor precision, which we have traced primarily to the drag link and bellcrank. These parts will be replaced with a ball-jointed drag link and modified bellcrank that can accept a tapered ball-joint stud.

- The turning radius is inadequate. Going up Kodachadri required 3 point turns in multiple places. Need to understand what our options are to improve this.

- Brakes are currently not working to 100% potential. They need to be pumped twice to get full stopping power. This could be faulty seals in the MC or pad knockback, not sure which. We will start with the booster/MC.

- There are many squeaks, rattles, noises and assorted harshness which I need to learn to ignore. This is not a Land Cruiser.

Our first upgrades were a good set of head lights and turn signals. The roads in this region are treacherous and a callous attitude prevails, with many vehicles permanently on their high beams or illegal driving lights. In our experience over the past few days, a flash of the LED light bar is enough to set right 90% of these idiots.

Hardtop MM550 : A family friendly offroader joins Team-BHP-img20151212wa0010.jpg

The setup is

- 22" Hella LED light bar that delivers about 5000 lumens of raw 6000k white light. The optics are not too great which means there is a lot of scatter. Perfect off-road and tight ghat sections when there is no incoming traffic. Turning this thing on makes you forget you're driving at night, quite literally.

- Hella 1200 fog lamps mounted as low and wide as practical. We were unable to test the performance although I doubt they will be worse than no fog lamps.

- Tecniq USA LED 2-function marker+turn signals. These are PC rated meaning they are viewable from a 90 deg angle. Most LED lights have poor visibility from off-center.

- Tecniq USA 2.5" round LED marker lights. The function of these is to fill the ugly holes next to the front grill and look cool due to their radial light pattern.
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Old 16th December 2015, 10:53   #227
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Wow, a very different look. The LED lights have changed the character significantly.

I had told you that the engine is the best part about this Jeep. At Kodachadri it must have raised eyebrows among the local Jeepers.

BTW, what did you mean by 4 speed transmission is almost superfluous?
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Old 16th December 2015, 11:13   #228
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Definitely, we got a lot of interest from drivers and tourists alike. They wanted to know if it's a Thar or a DI turbo engine etc. We were secretive with where we got the lights from lest it falls into the wrong hands hehehe. We used 4-Lo with the front hubs unlocked in order to reduce driver fatigue during climb as well as descent. It was mostly done in 3rd gear .

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BTW, what did you mean by 4 speed transmission is almost superfluous?
I meant that the engine has so much torque, the gearbox is almost not needed.
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Old 16th December 2015, 11:48   #229
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We used 4-Lo with the front hubs unlocked in order to reduce driver fatigue during climb as well as descent.
You turned it into a RWD.

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It was mostly done in 3rd gear .
Conditions must be dry now. It is more challenging in monsoons.

Will you be around during Christmas, I should be back in Manipal by then. You can meet the Udupi offroaders.
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Old 23rd December 2015, 16:15   #230
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I'd like to hear experts' opinion on this. This spacer for the transmission mount cross-member worries me a little bit. Is this a common practice for modified vehicles or is this an OEM part? I hope to get it replaced with a tubular steel or solid steel spacer.

Hardtop MM550 : A family friendly offroader joins Team-BHP-img_20151222_121956972.jpg

Hardtop MM550 : A family friendly offroader joins Team-BHP-img_20151222_122004793.jpg

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Last edited by ananthkamath : 23rd December 2015 at 16:21.
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Old 23rd December 2015, 21:54   #231
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That is definitely not stock. You can get the spacer from any of the Mahindra pickups, which will be like a wedge.
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Old 24th December 2015, 11:04   #232
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Quote:
Originally Posted by ananthkamath View Post
1. Engine and transmission are top notch in terms of power delivery, if not in refinement. The low range ratio of 2.5:1 seems very adequate for the impressive amount of torque put out by the DI diesel. 2. Steering has excessive play resulting in very poor precision, which we have traced primarily to the drag link and bellcrank. These parts will be replaced with a ball-jointed drag link and modified bellcrank that can accept a tapered ball-joint stud. 3. The turning radius is inadequate. 4. Brakes are currently not working to 100% potential. They need to be pumped twice to get full stopping power. 5. There are many squeaks, rattles, noises and assorted harshness. 6. A flash of the LED light bar is enough to set right 90% of these idiots.
Dear Ananthkamath - sorry for delayed reply, I just now remembered your request! My reply is as follows:

1. Yes, this is a strong point but it needs to be used carefully. 4WD Low range 3rd gear is most effective as it tracts the power curve nicely.
2. It may be a simple matter of adjusting the backlash, check it out before you do anything major. Preload the kingpin bearings properly otherwise you will get death wobble.
3. This has always been an issue, this was one of the things which got resolved with the NGCS.
4. Seems to be a simple matter of ensuring seal conformance.
5. A couple of hours spent on a couple of Sunday mornings should set things right.
6. Please get rid of this thing or use it very carefully. A guy in a white Fortuner flashed something like this when I was on the opposite side. I gave him a piece of my mind! .

The powertrain is fitted at 6 degrees north-south (means longitudinally). This is done to ensure articulation clearance of the cylinder block and sump with the front axle in spike test. Remember that in the CL / MM architecture, the front axle moves up by 99mm during "spike" (panic braking without disengaging the clutch till the engine stops). The spacers that you show in the photograph are absolute aftermarket nonsense. You must remove them and throw them out. See the bolts used, the gearbox cross member will fall off one day, be careful. For non-NGCS vehicles (like yours), we had designed and used aluminium wedges having 6 degrees angle built into them. Remember that you will need reverse wedges above the long members to ensure correct assembly. These wedges are still available at good Jeep shops. Buy and use them with correct length of M10*1.25 size bolts with nyloc nuts.

Best regards,

Behram Dhabhar
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Old 24th December 2015, 12:52   #233
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Dear Ananthkamath - These wedges are still available at good Jeep shops. Buy and use them with correct length of M10*1.25 size bolts with nyloc nuts.
I understood importance of these wedges and spike arrestor after few costly damages.

Dear Ananthkamath: please make sure you spike arrestor installed as well, though both (wedges and spike arrestor) are not costly but very very difficult to find. I had to scavenge from a scrap yard after weeks of search.
Also, please make sure kingpin bearings are good and set correctly, else you wont be able to completely resolve wobble issue.

Regards,
Shubhendra Singh
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Old 24th December 2015, 15:20   #234
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Quote:
Originally Posted by DHABHAR.BEHRAM View Post

1. Yes, this is a strong point but it needs to be used carefully. 4WD Low range 3rd gear is most effective as it tracts the power curve nicely.
2. It may be a simple matter of adjusting the backlash, check it out before you do anything major. Preload the kingpin bearings properly otherwise you will get death wobble.
3. This has always been an issue, this was one of the things which got resolved with the NGCS.
4. Seems to be a simple matter of ensuring seal conformance.
5. A couple of hours spent on a couple of Sunday mornings should set things right.
6. Please get rid of this thing or use it very carefully. A guy in a white Fortuner flashed something like this when I was on the opposite side. I gave him a piece of my mind! .

The powertrain is fitted at 6 degrees north-south (means longitudinally)... For non-NGCS vehicles (like yours), we had designed and used aluminium wedges having 6 degrees angle built into them. Remember that you will need reverse wedges above the long members to ensure correct assembly. These wedges are still available at good Jeep shops. Buy and use them with correct length of M10*1.25 size bolts with nyloc nuts.
Hello Mr. Dhabhar - Thank you very much for the timely reply. Your input is very much appreciated. My comments below:

1. I noticed this when climbing a deeply rutted mountain path, in fact 3rd LO had better driveability than 2nd LO in most places.

2. & 3. Based on some input in my other thread (MM550: Issue with steering precision & turning radius), I'm thinking about changing the steering to the Armada type since it costs the least in terms of time and effort, while still apparently providing a meaningful reduction in steering effort and turning radius.

4. & 5. Thanks, will do.

6. I lugged it here from the US along with other painstakingly procured parts at the cost of my wife's patience for a few days. I'm not going to get rid of it anytime soon. Offroad at slow speed, it is a boon. I assure you that the only times we turned it on on-road was to make our abilities clear to the opposite parties who failed to turn off high beams after repeated warnings.

As far as the wedges go, it is a strange design indeed. The 6 degrees could very well have been incorporated into the transmission mounts, but I do understand your development guys at the time would've had their own constraints to work to. We'll try to procure those parts, if not we'll have to find/make a substitute.


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Dear Ananthkamath: please make sure you spike arrestor installed as well, though both (wedges and spike arrestor) are not costly but very very difficult to find.
Thanks Shubhendra - Yes, the spike arrester is on my list as well. Any chance you have detailed photos of its installation on a MM with a KMT90?
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Old 24th December 2015, 16:37   #235
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Thanks Shubhendra - Yes, the spike arrester is on my list as well. Any chance you have detailed photos of its installation on a MM with a KMT90?
Search search!!

Spikee
http://www.team-bhp.com/forum/4x4-te...ml#post2532881 (Problems after converting MM540XD 2WD to 4WD)

Wedge issue
http://www.team-bhp.com/forum/4x4-ve...ml#post2278361 (Got Jeep! CJ3B Hurricane.)

There is a ton of info inside 4x4 section, use the search function and read up.
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Old 24th December 2015, 18:23   #236
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Hi Jaggu - Thanks for the links, I've seen those before. I wanted to check with Shubhendra to see if he had pics of the OEM part with the concentric limiting tube. Judging by the witness marks on my radiator, the mechanical fan appears to have crashed multiple times into it. I'm willing to bet forward movement is more severe as well as more frequent than rearward.

As far as search advice goes, no offense meant, but you're preaching to the choir. I've been part of more forums than I care to count since 2002 and both benefited as well as contributed good technical info. One search on this forum with my username should confirm this .
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Old 28th December 2015, 11:16   #237
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Quote:
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Thanks Shubhendra - Yes, the spike arrester is on my list as well. Any chance you have detailed photos of its installation on a MM with a KMT90?
Installing spike arrestor is pretty straight forward. it has nut bolt pattern at one end and round ball at another end. That round ball gets fitted on a Yoke in GB cross member and nut bolt side in bell housing.

regards,
Shubhendra
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