Go Back   Team-BHP > Buckle Up > 4x4 & Off-Roading > 4x4 Technical


Reply
 
Thread Tools Search this Thread
Old 26th September 2012, 16:09   #16
BHPian
 
Frankenstein's Avatar
 
Join Date: Jan 2011
Location: Bangalore/hyderabad
Posts: 330
Thanked: 269 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by svsantosh View Post
Sir, how much is it? just for our knowledge! Couple of friends decided against the Crde for the same reason about cost of the critical CV joint. I recall Tanzeem/brothers spending close to 25K (?) for their scorpio's, is it the same figure?
Heard its 38k
Frankenstein is offline   (1) Thanks Reply With Quote
Old 26th September 2012, 23:38   #17
BHPian
 
swastikviji's Avatar
 
Join Date: Feb 2009
Location: Bangalore
Posts: 417
Thanked: 158 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by svsantosh View Post
Sir, how much is it? just for our knowledge! Couple of friends decided against the Crde for the same reason about cost of the critical CV joint. I recall Tanzeem/brothers spending close to 25K (?) for their scorpio's, is it the same figure?
Santosh RH side CV will be around 32+tax, we just got a used one by paying 8K,
swastikviji is offline   Reply With Quote
Old 27th September 2012, 08:58   #18
Distinguished - BHPian
 
Join Date: Jul 2007
Location: MUMBAI
Posts: 3,059
Thanked: 4,571 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by DirtyDan View Post
Jaskirat, please be careful, you may now be attacked by a middle-aged fanatical engineer. This one doesn't drive a train usually.
Dear Ken - good comment I say! A certain "middle aged fanatical engineer" happens to be attitudinally 23 years old. He is also a decent sort of chap, why would he attack anybody? He does not seem to have understood the train bit. Please clarify.

Dear all - as all of you know my reaction, this time it is better that I refrain from saying anything except "best of luck, to each his own"!

Best regards,

Behram Dhabhar
DHABHAR.BEHRAM is offline   Reply With Quote
Old 27th September 2012, 12:49   #19
Distinguished - BHPian
 
4x4addict's Avatar
 
Join Date: Nov 2007
Location: Chennai
Posts: 3,889
Thanked: 2,303 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Dear: Jaskirat,

It is a very interesting project, but the way I look at it, the Thar CRDe offers me nothing except the powerful engine. I would not buy the Thar CRDe for doing any intense stuff offroad. The Scorpio/Thar CRDe 4WD platform is not meant to do any heavy lifting off road. It was designed to drive at 150 kmph to a mud bath, play in the mud bath and return home at 150 kmph. My advise for anyone who want to build a proper off-roader is to start with an NGCS MM550 or a Thar DI as the base vehicle and build up on it. I dont' feel it is worth spending 8 lakhs On the road and doing any drastic suspension changes. I got a message on face book from a Thar CRDe owner saying that he has broken his front CV joint and the dealer has told him that it is because he put 31 inch tires. No point in having an off-roader and being able to run it only with 235 mm tires.

I am not saying that the Thar CRDe is a bad vehicle. It was designed primarily for on road with moderate off-road usage. I

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
Dear all - as all of you know my reaction, this time it is better that I refrain from saying anything except "best of luck, to each his own"!
As you have pointed out earlier, your team designed the Thar CRDe under lot of limitations imposed on you buy corporate bureaucracy/budget constraints etc. You have done a very very good job of it and the vehicle makes sense for the intended market and we can definitely say that your team's efforts are a success. But unfortunately, the vehicle doesn't meet the needs for hard core off-roading and some of use are bound to try to get around the limitations imposed by corporate/budget constraints.

Heck people even customize the Wrangler Rubicon and Defender 90 which are extremely potent just the way it comes out of the factory.
4x4addict is offline   (12) Thanks Reply With Quote
Old 27th September 2012, 14:23   #20
BHPian
 
Jaskirat's Avatar
 
Join Date: Jun 2008
Location: Chandigarh
Posts: 175
Thanked: 173 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by AlphaKilo View Post
Jaskirat, top class!! Did you do any significant changes to the suspension set up? I see two hydraulic(or are they gas charged?) shock absorbers. Can you post some pics of the suspension setup and axle mount, drive shaft to front axle?

The Power steering lining seems to be inbetween the differential and the chassis(pic 1 & 2) can you explain that further? What happens when the vehicle is not articulating? Is there a sufficient clearance?(I am sure you would have thought on this, but just curious to know! Don't misundertand me friend.)

1. Is there is any raise/loss in approach angle?

2. How practical is this OKBJ as a daily commute, other than for hard core off roading?

(a naive, non-technical question!)
3. What about the legalities?
Is it still road legal?(with this modification!)

Thanks!
Hi AlphaKilo,

The suspension was totally changed. As you can see, the Thar now rides on leafsprings. Yes, we have installed twin Hydraulic shock-absorbers, which we thought of using to compensate for additional weight of the CRDE.

As conveyed earlier, I am waiting for Karan Bali, the owner of the Thar to bring the vehicle for a photo shoot on Sunday. I will post some more pictures.

The PS remains at its original location. There is more than sufficient clearance between the PS piping and the differential.

1. Since the Thar rides a bit higher now, it now has a slightly better angle of approach. We have not measured the difference.

2. Without doubt, a fixed axle cannot compete with the level of comfort that IFS offers on road. Nevertheless, it is quite livable as a daily commuter also. Off-road, in my opinion, fixed axle outperforms the IFS any day.

3. Any modification to the vehicle from its standard manufacturer's specifications renders it illegal as per Central Motor Vehicle Act. Rest I will leave for the legal eagles to interpret and respond.

Cheers

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
Dear Ken - good comment I say! A certain "middle aged fanatical engineer" happens to be attitudinally 23 years old. He is also a decent sort of chap, why would he attack anybody? He does not seem to have understood the train bit. Please clarify.

Dear all - as all of you know my reaction, this time it is better that I refrain from saying anything except "best of luck, to each his own"!

Best regards,

Behram Dhabhar
Mr. Behram, your comments and advice is invaluable. Some of us might sometimes experiment and throw caution-to-the-wind, but we never undermine the technically sound feedback from stalwarts like you.

Wish you did not refrain from giving your feedback.

Regards, Jaskirat

Quote:
Originally Posted by 4x4addict View Post
Dear: Jaskirat,

It is a very interesting project, but the way I look at it, the Thar CRDe offers me nothing except the powerful engine. I would not buy the Thar CRDe for doing any intense stuff offroad. The Scorpio/Thar CRDe 4WD platform is not meant to do any heavy lifting off road. It was designed to drive at 150 kmph to a mud bath, play in the mud bath and return home at 150 kmph. My advise for anyone who want to build a proper off-roader is to start with an NGCS MM550 or a Thar DI as the base vehicle and build up on it. I dont' feel it is worth spending 8 lakhs On the road and doing any drastic suspension changes. I got a message on face book from a Thar CRDe owner saying that he has broken his front CV joint and the dealer has told him that it is because he put 31 inch tires. No point in having an off-roader and being able to run it only with 235 mm tires.

I am not saying that the Thar CRDe is a bad vehicle. It was designed primarily for on road with moderate off-road usage. I



As you have pointed out earlier, your team designed the Thar CRDe under lot of limitations imposed on you buy corporate bureaucracy/budget constraints etc. You have done a very very good job of it and the vehicle makes sense for the intended market and we can definitely say that your team's efforts are a success. But unfortunately, the vehicle doesn't meet the needs for hard core off-roading and some of use are bound to try to get around the limitations imposed by corporate/budget constraints.

Heck people even customize the Wrangler Rubicon and Defender 90 which are extremely potent just the way it comes out of the factory.
Hi 4x4addict,

I totally agree with you about the Thar CRDE / Scorpio platforms. Excellent for road / soft off-road, but not for hard off-road driving. This the owners realize only after having spent the money and hitting the rough and that too hard.

This particular conversion was done after the Thar had broken two CV Joints and damaged the gearbox. Some of this can be attributed to Karan Bali's (the owner of the Thar) extremely rough driving style. Lets see how the solid axle copes with his driving.

I too prefer a MM550XD over Thar CRDE if off-road driving is the only objective. I have seen many MM550s running on 31 / 33 inch tyres without any issues. We have even modified an old MM540 with 475DI engine and it runs on 33 inch tyres without any problem of axles breaking. (Picture attached).

I will post some more pictures of the Thar on Sunday when Karan brings it to the workshop for a photo shoot.

Regards, Jaskirat
Attached Thumbnails
Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-r-dd-spoa-1.jpg  

Jaskirat is offline   (8) Thanks Reply With Quote
Old 27th September 2012, 19:09   #21
BHPian
 
dhawcash's Avatar
 
Join Date: Dec 2008
Location: jaipur
Posts: 124
Thanked: 140 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

hello Jaskirat.

A Novel approach regarding the steering system.

Have you mounted the steering rack to the axle or is it hanging from the chassis only?

Sorry to be a spoilsport, but the pictures suggest its on the chassis. If that is the case i think you need to rework the system. The present setup would cause binding and ultimately failure of the rack and pinon tie rods.

As it is a power steering i dont think the binding would be noticable to the driver.

At least remove one of the rack and pinon tierods to eliminate the binding. This however will cause the wheels to steer with as the suspension moves. basically , the geometries seem to be wrong/clashing to me.

If you have mounted the rack on the axle only, sorry about the blabbering above
But even in that case managing a flexible hydraulic link to the rack moving with the axle would be quiet a task. not to mention the actual mechanical link from the steering wheel to the pinon gear.
dhawcash is offline   (4) Thanks Reply With Quote
Old 27th September 2012, 21:39   #22
BHPian
 
Jaskirat's Avatar
 
Join Date: Jun 2008
Location: Chandigarh
Posts: 175
Thanked: 173 Times
Default

Quote:
Originally Posted by dhawcash
hello Jaskirat.

A Novel approach regarding the steering system.

Have you mounted the steering rack to the axle or is it hanging from the chassis only?

Sorry to be a spoilsport, but the pictures suggest its on the chassis. If that is the case i think you need to rework the system. The present setup would cause binding and ultimately failure of the rack and pinon tie rods.

As it is a power steering i dont think the binding would be noticable to the driver.

At least remove one of the rack and pinon tierods to eliminate the binding. This however will cause the wheels to steer with as the suspension moves. basically , the geometries seem to be wrong/clashing to me.

If you have mounted the rack on the axle only, sorry about the blabbering above
But even in that case managing a flexible hydraulic link to the rack moving with the axle would be quiet a task. not to mention the actual mechanical link from the steering wheel to the pinon gear.
Hi dhawkash,

The steering rack is mounted on the chassis at its original location. So far we have not experienced any tie rod binding, or we are missing the tell tale signs.

We have tried to keep the tie rod angles similar to the original setup. If you see carefully, the steering arms have a downward angle which allows free movement of the tie rods without binding. At least that is the idea.

Cheers, Jaskirat
Jaskirat is offline   Reply With Quote
Old 27th September 2012, 21:44   #23
Distinguished - BHPian
 
dhanushs's Avatar
 
Join Date: Oct 2009
Location: Bathery/BLR
Posts: 3,406
Thanked: 3,930 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by dhawcash View Post
Have you mounted the steering rack to the axle or is it hanging from the chassis only?


Sorry to be a spoilsport, but the pictures suggest its on the chassis. If that is the case i think you need to rework the system. The present setup would cause binding and ultimately failure of the rack and pinon tie rods.
Hi dhawcash, I second you. Jaskirat mentioned that the rack in mounted on the chassis. The main issue will be the load on the tie rods, which is not designed for that purpose.

Quote:
At least remove one of the rack and pinon tierods to eliminate the binding. This however will cause the wheels to steer with as the suspension moves. basically , the geometries seem to be wrong/clashing to me.
This, IIRC, is called bump steer.

Jaskirat, the way my inexperienced eye sees it, your entire set up (rack on the chassis, tie rods, and axle ) is like a quadrilateral with a fixed perimeter. ie, when there is suspension travel, the spindle casing is pulled in/pushed out, so that the perimeter remains same. This causes the wheels to steer in an unfavorable way.

ie, whist suspension travel, when one wheel moves up and the other down, the wheel moving down is pulled inside (toe-in), and vice versa.

A way around this is mounting the rack on the axle. But, then, you will need a telescopic steering column. Now, at speeds I dont think, here, there is any column which is capable of providing that much travel, that fast.

This is the main issue with the set up. Maybe experts can comment more.

Also, IMO, steering geometry is very important, and unless backed by precise calculations, altering it would cause irritating issues!
dhanushs is offline   (2) Thanks Reply With Quote
Old 28th September 2012, 09:06   #24
BHPian
 
dhawcash's Avatar
 
Join Date: Dec 2008
Location: jaipur
Posts: 124
Thanked: 140 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Hi Jeskirat,

I'll explain why i think there is a problem(s).

1.Bumpsteer As pointed out by dhanush sir (inexperienced eyes- really!?)
Quote:
the way my inexperienced eye sees it, your entire set up (rack on the chassis, tie rods, and axle ) is like a quadrilateral with a fixed perimeter. ie, when there is suspension travel, the spindle casing is pulled in/pushed out, so that the perimeter remains same. This causes the wheels to steer in an unfavorable way.

ie, whist suspension travel, when one wheel moves up and the other down, the wheel moving down is pulled inside (toe-in), and vice versa.

A way around this is mounting the rack on the axle. But, then, you will need a telescopic steering column. Now, at speeds I dont think, here, there is any column which is capable of providing that much travel, that fast.
According to this theory, the thar should be bump steering like crazy, but its not. here lies problem # 2

2.clash in geometries
The rack and pinon on a solid axle should be causing crazy bump steer, but its not. why?
The bottom tie rod is trying its best to keep the wheels parallel ( at least when the steering is pointing straight ahead- rest of the times it follows ackerman geometry) while the upper ones are trying to produce bump steer.

In a nutshell, both the tie rods are trying to have their own say and till now the bottom one is winning.
but sooner or later, one of them is going to give up.Some thing is gonna break!
I predict the upper tie rods would buckle or just snap off due to the stressful nature of this conflict. Other parts like ball joints would wear out faster as well.

the power steering is acting smart and enjoying the show without letting you feel the tremors of conflict here.

PS: to understand in a better way, disconnect the lower tierods and go for a drive on uneven tarmac. the thar would behave like a mad boar. ( drive slow!)
Or better still drive up an articulation ramp. you'll find both wheels pointing at different directions.
dhawcash is offline   (7) Thanks Reply With Quote
Old 28th September 2012, 10:23   #25
Team-BHP Support
 
tsk1979's Avatar
 
Join Date: Feb 2005
Location: New Delhi
Posts: 22,850
Thanked: 15,406 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Drive the vehicle on a normal highway(reasonably good surface) at 80-90kmph. Can you keep a straight line without constant steering input every time road undulates? I think not.
In IFS vehicles, when center link road ends give away, this behaviour is seen. Since you have converted to Solid axle, you will be seeing this all the time. Not a very good thing, unless you never plan to exceed 50kmph.
This mod is definitely ambitious, but in the long run it will cause far worse problems than perceived problems of IFS setup.
From personal experience IFS is weak, no doubt, but replacing tie rods and Center link rod every 10,000kms (should be less than 2000rs in open market) is a better solution.
Maybe you can keep a lookout for "more robust" center link roads and tie rods, designed for a heavier vehicle, and try to put it on the thar if you want a tougher front suspension.
What you have done is a mechanical wonder, but an engineering disaster. Now you can understand the horror some people have shown at this setup
tsk1979 is offline   (1) Thanks Reply With Quote
Old 28th September 2012, 11:45   #26
BHPian
 
Jaskirat's Avatar
 
Join Date: Jun 2008
Location: Chandigarh
Posts: 175
Thanked: 173 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by dhawcash View Post
Hi Jeskirat,

I'll explain why i think there is a problem(s).

1.Bumpsteer As pointed out by dhanush sir (inexperienced eyes- really!?)


According to this theory, the thar should be bump steering like crazy, but its not. here lies problem # 2

2.clash in geometries
The rack and pinon on a solid axle should be causing crazy bump steer, but its not. why?
The bottom tie rod is trying its best to keep the wheels parallel ( at least when the steering is pointing straight ahead- rest of the times it follows ackerman geometry) while the upper ones are trying to produce bump steer.

In a nutshell, both the tie rods are trying to have their own say and till now the bottom one is winning.
but sooner or later, one of them is going to give up.Some thing is gonna break!
I predict the upper tie rods would buckle or just snap off due to the stressful nature of this conflict. Other parts like ball joints would wear out faster as well.

the power steering is acting smart and enjoying the show without letting you feel the tremors of conflict here.

PS: to understand in a better way, disconnect the lower tierods and go for a drive on uneven tarmac. the thar would behave like a mad boar. ( drive slow!)
Or better still drive up an articulation ramp. you'll find both wheels pointing at different directions.
Wow, what a start to a day. Some very insightful feedback, which I definitely need to understand carefully and act upon. Mounting the R&P on to the axle was never an option that we had. So had to work with the steering on the chassis. I could have opted for a RCB Type steering, but chose to follow the route of retaining the R&P.

While whatever has been mentioned is technically valid, but the Thar drives just fine even at fairly high speeds.

Thanks for the invaluable feedback.

Quote:
Originally Posted by tsk1979 View Post
Drive the vehicle on a normal highway(reasonably good surface) at 80-90kmph. Can you keep a straight line without constant steering input every time road undulates? I think not.
In IFS vehicles, when center link road ends give away, this behaviour is seen. Since you have converted to Solid axle, you will be seeing this all the time. Not a very good thing, unless you never plan to exceed 50kmph.
This mod is definitely ambitious, but in the long run it will cause far worse problems than perceived problems of IFS setup.
From personal experience IFS is weak, no doubt, but replacing tie rods and Center link rod every 10,000kms (should be less than 2000rs in open market) is a better solution.
Maybe you can keep a lookout for "more robust" center link roads and tie rods, designed for a heavier vehicle, and try to put it on the thar if you want a tougher front suspension.
What you have done is a mechanical wonder, but an engineering disaster. Now you can understand the horror some people have shown at this setup
Thanks for your very frank and candid feedback. An Electronics Engineer trying our Mechanical stuff is a disaster in itself. But I am sure to figure out a way forward.

Quote:
Originally Posted by dhanushs View Post
Hi dhawcash, I second you. Jaskirat mentioned that the rack in mounted on the chassis. The main issue will be the load on the tie rods, which is not designed for that purpose.

This, IIRC, is called bump steer.

Jaskirat, the way my inexperienced eye sees it, your entire set up (rack on the chassis, tie rods, and axle ) is like a quadrilateral with a fixed perimeter. ie, when there is suspension travel, the spindle casing is pulled in/pushed out, so that the perimeter remains same. This causes the wheels to steer in an unfavorable way.

ie, whist suspension travel, when one wheel moves up and the other down, the wheel moving down is pulled inside (toe-in), and vice versa.

A way around this is mounting the rack on the axle. But, then, you will need a telescopic steering column. Now, at speeds I dont think, here, there is any column which is capable of providing that much travel, that fast.

This is the main issue with the set up. Maybe experts can comment more.

Also, IMO, steering geometry is very important, and unless backed by precise calculations, altering it would cause irritating issues!
Dear dhanush,

Thanks for your detailed feedback. I am sure to gain a lot from it. Regards, Jaskirat
Jaskirat is offline   Reply With Quote
Old 28th September 2012, 15:27   #27
Distinguished - BHPian
 
4x4addict's Avatar
 
Join Date: Nov 2007
Location: Chennai
Posts: 3,889
Thanked: 2,303 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by tsk1979 View Post
From personal experience IFS is weak, no doubt, but replacing tie rods and Center link rod every 10,000kms (should be less than 2000rs in open market) is a better solution.
IFS is not inherently a weak option if designed and build for robustness which the Scorpio/Thar CRDe is definitely not. The owner didn't not change to Solid axcle due to the cost issue with replacing tie rod or center link rod. The problem is the CV joints of the front drive shaft. They tend to break when put a lot of torque on the front wheels and try to negotiate a turn at the same time. The front axle/CV joint is not available in the open market and cost about 40K with the dealer. This is the weakest point in the Thar and not the IFS per se.

Toyota/Mitsubishi etc have been running IFS for many competition events for years. The difference is in the way Mahindra has implemented it due to lack of resources engineering/money.
4x4addict is offline   (6) Thanks Reply With Quote
Old 28th September 2012, 16:15   #28
Distinguished - BHPian
 
Join Date: Jul 2007
Location: MUMBAI
Posts: 3,059
Thanked: 4,571 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by 4x4addict View Post
Toyota/Mitsubishi etc have been running IFS for many competition events for years. The difference is in the way Mahindra has implemented it due to lack of resources engineering/money.
Dear Tini - look at the front suspension of Ssangyong Rexton / Musso! . Then look at Thar CRDe. Simple, my dear friend!

Dear Jaskirat - what comments do I give? Very well, as you want them, here goes - it needs to start from the FAW / RAW which will get translated into a DMU (digital mock up) which needs to answer the zillion dollar question on what the front axle spike dimension will be and how the axle will be controlled to achieve it with good working clearance with the sump. Then there will be numerous and difficult thousand dollar questions like driving dynamics etc. Then there will be numerous and relatively less difficult questions like the propeller shaft angles, necking phenomenon / caster issues due to power steering, changes in scub radius etc. It is only when the DMU gets cleared in all respects (including the infamous CMVR, the biggest "Ravana" of them all) that a mule prototype can be built. Then comes the still more difficult job of testing and verification of prototypes at 4 stages of build before vehicle "J1" (Job 1) is built. If at all released and by the time the BOM (Bill of Material) is released, it's like "whew"! Then there are quality issues to contend with before the product finally hits the showrooms.

Product Engineering and Vehicle Integration is not an easy job!

I do not know whether you have gone through any analytical steps, therefore, please be very very careful when you drive this vehicle. Do not take any chances whatsoever. Reliability is very important and must not be compromised.

Therefore, "Best of luck, to each his own".

Best regards,

Behram Dhabhar
DHABHAR.BEHRAM is offline   (5) Thanks Reply With Quote
Old 28th September 2012, 19:36   #29
Senior - BHPian
 
headers's Avatar
 
Join Date: May 2006
Location: Greater Chennai
Posts: 4,548
Thanked: 424 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by DHABHAR.BEHRAM View Post
what comments do I give? Very well, as you want them, here goes -
Sir, Please - lets make it simple - An automobile company manufacturing automobiles with World Class Manufacturing standards should not have difficulty in trying to build a J1 and have it tested.

With modern tools [CAD/CAE, solid modelling. rapid prototyping etc] one need not have to struggle too much if the basics are in place!

If I may say so, the THAR is selling good numbers in spite of the way it drives because of lack of competition, not because of its superior design.
headers is offline   (7) Thanks Reply With Quote
Old 28th September 2012, 20:57   #30
BHPian
 
Jaskirat's Avatar
 
Join Date: Jun 2008
Location: Chandigarh
Posts: 175
Thanked: 173 Times
Default Re: Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle

Quote:
Originally Posted by DHABHAR.BEHRAM View Post

Dear Jaskirat - what comments do I give? Very well, as you want them, here goes .....

.... Product Engineering and Vehicle Integration is not an easy job!

I do not know whether you have gone through any analytical steps, therefore, please be very very careful when you drive this vehicle. Do not take any chances whatsoever. Reliability is very important and must not be compromised.


Behram Dhabhar
Dear Sir,

I guess I got far more than what I had asked for. If I was a Mechanical Engineer working for a large organization like Mahindra, and had resources at my disposal, I would definitely like to follow the route charted by you. (Obviously CMVR is avoidable.) But alas, I am Electronics and Telecommunication Engineer, who while understands where you are coming from, is also an enthusiast and willing to try out few things.

I might not have analysed the design in a structured manner as detailed by you, but definitely tried to keep some basics like sump clearance, shaft angle, suspension travel etc. in mind when coming up with this setup. So far it appears to work fairly fine, but reliability is something we will have to wait and watch.

I have been part of a supply chain to automotive industry and do not undermine the importance of RAW, FAW, DFMEA, PFMEA, DMU etc., but when has enthusiasm been held hostage to these.

I will definitely take your advise ask Karan the owner of the Thar to be careful
while driving.

Quote:
Originally Posted by dhawcash View Post

The bottom tie rod is trying its best to keep the wheels parallel ( at least when the steering is pointing straight ahead- rest of the times it follows ackerman geometry) while the upper ones are trying to produce bump steer.

In a nutshell, both the tie rods are trying to have their own say and till now the bottom one is winning.
but sooner or later, one of them is going to give up.Some thing is gonna break!
I don't understand why the two tie rods will oppose each other. Even if their is bump steer and the upper tie rod is pushing the wheels in a particular direction, the lower tie rod, which is without the drag link, would simply follow the direction of push. Bump steer notwithstanding.

I have taken some pictures today of the Thar on a Ramp. Just sharing these to see if some more interesting feedback comes my way.

Regards

Jaskirat
Attached Thumbnails
Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-11.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-7.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-8.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-5.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-solid-axle.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-10.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-2.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-12.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-3.jpg  

Mahindra Thar - *Converted* Independent Front Suspension to Solid Axle-thar-ramp-9.jpg  

Jaskirat is offline   (7) Thanks Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Hyundai Tucson - 138,000 kms done and front left axle replaced anandpadhye Long-Term Ownership Reviews 436 15th August 2017 07:01
Why are car makers abandoning independent rear suspension? directinjection Technical Stuff 35 31st January 2017 01:57
Is Independent Front Suspension (IFS) good for offroading? Samurai 4x4 Technical 142 18th March 2014 12:06
Can we swap the Thar's IFS with the MM550's rigid axle? jeepbug 4x4 Technical 17 5th June 2012 10:46


All times are GMT +5.5. The time now is 07:54.

Copyright 2000 - 2017, Team-BHP.com
Proudly powered by E2E Networks