[Turbanator]

Originally Posted by Comrade

Aren’t suspension nuts suppose to have split pin aka cotter pin to prevent this failure? Doesn’t Mahindra use them?

I see it being used by Toyota when I search front suspension for Fortuner/ Hilux.

Originally Posted by ferrarirules

I found another image of the suspension setup alone from Autocar India. It also shows a single joint on top

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Yes, It's clear from that schematic diagram. I tried to compare with Fortuner, and though the setup is similar, I see a difference in implementation, and most importantly, as Comrade mentioned, you can see split pins on Toyota's.



Pic. source - video by Gopro- Tik Pluak Daeng

[gururajrv]

I seriously do not understand as to why Quality Checks at Mahindra and Tata are this bad. Forget service being a hit or a miss. It's the quality of the vehicle which seems to always being a hit or a miss amongst customers. Although the % is lower, it does call for some serious digging into from Mahindra's management stable.

Hope the car is back to it's good state now to service it's owner in the right way and keep the family safe at all times! Period.

[svsantosh]

Originally Posted by Turbanator

Is that Ball Joint the only place where this assembly is supported? I have doubts as this cannot carry all the load. Need to have a better picture for the first image.

Yes the upper ball joint and lower ball joint are the only two places where the knuckle transfers the load from wheel onto the upper arms and lower arms which in turn are held on by two bushes each.

This is called the double wishbone suspension. Nearly all trucks in the world have this, when I say truck I mean the F150 family, RAMs, Silverados, Hiluxs/ T-Forts, LCs and Lexus's.

Like it said earlier, it is a case of wrong workmanship and having worked in a Dubai garage/workshop for offroad trucks (as a passionate off-roader I changed my profession for a few years) I can vouch that this case of OP Scorpio is only a rare and bad example of a OEM assembly line error. Serious - yes, end of the world - no.

EDIT

Originally Posted by Comrade

Aren’t suspension nuts suppose to have split pin aka cotter pin to prevent this failure? Doesn’t Mahindra use them?

Brilliant observation. Few brands come with it, it is a 50 paisa solution (1 drill operation during manufacturing + 1 cotter pin) which can be seen in a few posts above. It really is a life saver.

[Turbanator]

Originally Posted by svsantosh

Yes the upper ball joint and lower ball joint are the only two places where the knuckle transfers the load from wheel onto the upper arms and lower arms which in turn are held on by two bushes each.

Maybe this picture explains better. I was curious about the support (or another control?) on this arm connected to the ball joint.

https://www.autoblog.com/2021/01/28/...ion-deep-dive/

[revver]

Appreciate the response on this thread. This is very insightful. Personally this has given me a chance to understand the 'Double wishbone' suspension set up better.

Originally Posted by ashivas89

Cannot get a good look at the alloy steering knuckle/ upright to see if the pocket that holds the ball joint shank has failed. If it hasn't, then clearly the nut that is supposed to hold the joint in place has come off, possibly due to not being fastened properly during assembly. If that is the case, then it is some scary QC by mahindra.

This seems to be the case here. The nut holding the upper joint fell down. Scary indeed. thread on the joint on Upper arm seems alright. So surely the nut wasn't tightened properly.

Originally Posted by Hemi6.2

Either the the knuckle broke from the upper joint or the fastener came loose, both are very serious QC issues.
Attaching a picture from the official review, encircling the area of concern.

Thanks. This picture shows the exact nut that has fallen off.

Originally Posted by svsantosh

To begin with, my eyes can see the fastener/thread is intact. Which means the nut was not torqued at all.

Exactly. thread looks intact.

Originally Posted by svsantosh

Yes, last but not least get these replaced FOC (free of cost)[/b]
Upper arm
Knuckle
Lower Arm
Axle + Wheel Hub
Link Rods
ABS/wheel speed Sensor
Steering Tie Rod
Brake hose (this is for sure!)
Rim (cannot see if its scratched)
Tyre (not clear as well)

Yes. spot on. this is what can be done now.

Originally Posted by Comrade

Aren’t suspension nuts suppose to have split pin aka cotter pin to prevent this failure? Doesn’t Mahindra use them?

Thanks for pointing this out. I don't know why Mahindra omitted this pin by design.

Originally Posted by Turbanator

Is that Ball Joint the only place where this assembly is supported? I have doubts as this cannot carry all the load. Need to have a better picture for the first image.

He didn't take a clear picture of the Knuckle. But the Knuckle has just one connection with the upper arm.

Originally Posted by ferrarirules

From the pic, it is clear that there is only one point where upper wishbone connects to suspension.
As the OP was turning the car right, the upper wishbone came undone and the tyre swung out from the top. The whole suspension setup is still intact (even steering arm is connected), only hub lost the upper support to stay upright.

Yes. you are exactly right. This is what happened.

Update: The dealership replaced the entire front suspension LH & RH, brake hose & also the front left wheel that had scratch. Owner took the vehicle back. But they are yet to hand over a detailed report of what & how it went wrong. I will update this thread when he receives the report.

Apart from this issue, the car is performing well. So i assume this is not a lemon but maybe a one off but serious lapse in QC by Mahindra. I doubt that the company will admit the mistake. But It's better to take a permanent corrective action in their Assembly, QC & PDI process & never let this happen again.

[svsantosh]

Originally Posted by Turbanator

Maybe this picture explains better. I was curious about the support (or another control?)

The visible nut/black rod is called anti-sway link rod, or anti-roll bar, so many terms. Basically it arrests the rolling-over feeling or the suspension dunking in totally during hard turns. This rod is interlinking L & R arms, in turns if the left suspension goes down the right suspension sort of holds it from going down all the way.

This (or rather lack of) is the reason many old scorpios, sumos, safaris especially used to feel like a land yatch during turns. It was nauseating as well scary and can cause a roll over if the COG shifts beyond a point.



(Pic credit, respective owners, got image from g-gle)

[Turbanator]

Originally Posted by svsantosh

The visible nut/black rod is called anti-sway link rod, or anti-roll bar, so many terms.

Thanks for taking the time to mark and explain.

What's this extra connecting tie rod in the Fortuner that I posted before? And where is this in the new scorpion?

[NomadSK]

Originally Posted by Turbanator

What's this extra connecting tie rod in the Fortuner that I posted before? And where is this in the new scorpion?

This looks like a sway/stabilizer link rod.

However, I’m not able to understand what has failed, ball joint has sheared off ? Or some bolt has come off ? Because a cotter pin won’t help if something has sheared off and will only help for bolt not coming off.

As far as I remember, The ball joint is attached to a control arm by pressing the joint into the arm or riveting the joint to the arm. A bit Confusing about what has failed.

[Turbanator]

Originally Posted by NomadSK

This looks like a sway/stabilizer link rod.

I mean this one. But it looks like we are going way off the topic. So to remain on the subject, is there a basic difference in the design on the new Scorpio vs. say Fortuner/ F-150 as I don't see such additional linkages on the Autocar drawing.

[svsantosh]

Originally Posted by Turbanator

I mean this one.

At a generic level, the anti sway bar (anti roll bar) is a set of linkages, rods that connect Left to the Right, both in front and rear suspensions (Only in fully independent suspensions). Anti sway bar is not found in rear dead axles in FWD cars but old Mahindras had them on Armadas and Boleros.

The component in your picture is part of the anti roll bar set up only, there are horizontal linkages and vertical linkages, they look different between each car, brand but purpose is same.

PS - Google for 'Jeep Rubicon Sway bar disconnect' feature
Offroader hate any anti roll bar.

[ferrarirules]

Originally Posted by revver

Update: The dealership replaced the entire front suspension LH & RH, brake hose & also the front left wheel that had scratch. Owner took the vehicle back. But they are yet to hand over a detailed report of what & how it went wrong. I will update this thread when he receives the report.

Apart from this issue, the car is performing well. So i assume this is not a lemon but maybe a one off but serious lapse in QC by Mahindra. I doubt that the company will admit the mistake. But It's better to take a permanent corrective action in their Assembly, QC & PDI process & never let this happen again.

Thanks for the update. Good that the entire front suspension was changed. But i differ with the "this is not a lemon" thought, think about this the owner payed his hard earned money for a new car and within two weeks my car is "repaired". The fit and finish of repair job at dealership is nowhere near to what comes from the factory. So had it been anywhere other than India, the company would have been forced to take the car back and provide a new one which was right the first time round.

Better Assembly/QC/PDI process will only happen if there are laws which force the manufacturers into not making serious mistakes.

Please note: My point is more about cars having major issues in first 30 days of ownership and going through major repairs to fix the issue.

[revver]

Originally Posted by ferrarirules

So had it been anywhere other than India, the company would have been forced to take the car back and provide a new one which was right the first time round.

In this particular case, getting the car replaced with a new one surely wasn't going to happen. Owner had to agree to the next best option of getting all the related parts replaced.

I wonder what would've happened if this failure of part led to an accident.
Similar incidents continue to happen until there are strict laws that punish OEM's for making defective cars & selling them to innocent customers.

[ferrarirules]

Originally Posted by revver

In this particular case, getting the car replaced with a new one surely wasn't going to happen. Owner had to agree to the next best option of getting all the related parts replaced.

I wonder what would've happened if this failure of part led to an accident.
Similar incidents continue to happen until there are strict laws that punish OEM's for making defective cars & selling them to innocent customers.

I think you are not getting my point, I am not challenging the resolution of this case. What the owner got is the best you get in India + some goodwill warranty.

I am trying to invoke a thought on how these cases can be avoided overall because they happening too often with absolutely new cars. For me, if my car has a major issue in the first few months, the new car feeling is gone.

[Habanero City]

Originally Posted by revver

Update: The dealership replaced the entire front suspension LH & RH, brake hose & also the front left wheel that had scratch. Owner took the vehicle back. But they are yet to hand over a detailed report of what & how it went wrong. I will update this thread when he receives the report.

Apart from this issue, the car is performing well. So i assume this is not a lemon but maybe a one off but serious lapse in QC by Mahindra. I doubt that the company will admit the mistake. But It's better to take a permanent corrective action in their Assembly, QC & PDI process & never let this happen again.

Glad that the issue is resolved.
Did the owner get extended warranty for the vehicle or the parts replaced?
That will help in building confidence.

On an another thought, while we do some limited PDI's, I think it would be better to take the new vehicle to the trusted tyre shop in order to check the alignment and balancing.

I am not sure how the factory sends the new vehicles to the delaers.

This first alignment and balancing would become the bench mark of the wheel settings for the vehicle and can be referred anytime later for comparison.
This would also help to find any of such issues as we can see the vehicle on the ramp for the first time.

[sandeepmdas]

Originally Posted by Habanero City

On an another thought, while we do some limited PDI's, I think it would be better to take the new vehicle to the trusted tyre shop in order to check the alignment and balancing.

While I agree with you wholeheartedly, let me also point out a practical difficulty. Many wheel alignment centers won't get themselves updated with suspension geometry data of newer models; at least those who are not major players or are not located in major towns. AFAIK this data is provided by alignment equipment manufacturers (like Hunter etc.) via their channel partners. Many alignment centers save money by skipping subscriptions for a while and wait for a new model to get popular.