[SS-Traveller]

Originally Posted by SPIKE ARRESTOR

When you shift back to 2H and did not reverse to disengage-> some noise comes; when you reverse ALH unlocks and the noise disappears this means your ALH locking / unlocking is OK. So, is the noise coming only in 4WD mode and not from the ALH, am I missing anything here?

ALH locking/unlocking is fine.

When ALH is locked, irrespective of whether I'm in 2WD or 4WD (either 4H or 4L) mode, the noise occurs. Unlock the ALH, the noise disappears.

I took the Scorpio offroad again today, and the noise was there. Once back on tarmac, I went back to 2WD mode, but did not unlock the ALH by reversing. I then drove a few km at moderate speeds (<60km/h), and felt the noise has reduced somewhat.

Is this the famous M&M auto-repair/auto-correction system at work? Is there a lubrication issue happening somewhere?

Originally Posted by anupmathur

Are you certain? The noise cannot quite be heard with the windows rolled up.

I usually don't offroad with the windows up. I try to listen for the click as the ALHs engage/disengage, as well as any other funny noises that may be there. And at least once a day I would roll down the windows and switch off the stereo to just listen to the noises any car I drive is making, for a few minutes. Better than running OBD as far as diagnosing impending problems go. Old habits die hard!

[SPIKE ARRESTOR]

Originally Posted by SS-Traveller

ALH locking/unlocking is fine.

When ALH is locked, irrespective of whether I'm in 2WD or 4WD (either 4H or 4L) mode, the noise occurs. Unlock the ALH, the noise disappears.

I took the Scorpio offroad again today, and the noise was there. Once back on tarmac, I went back to 2WD mode, but did not unlock the ALH by reversing. I then drove a few km at moderate speeds (<60km/h), and felt the noise has reduced somewhat.

ALH is not supposed to engage in 2WD mode, it engages only when torque supply is there. When you shift back to 2WD, please reverse to unlock ALH then see if there is any noise. Don't continue driving forward after shifting from 4WD to 2WD, this is a Standard operating procedure!

Spike

[suman]

Originally Posted by SPIKE ARRESTOR

Don't continue driving forward after shifting from 4WD to 2WD, this is a Standard operating procedure!

I think he understands that very well!

He's just trying to point out that when the hubs are locked, the noise reappears (whether in 4WD or just before unlocking, with switch back in 2H).

[Aroy]

Originally Posted by SS-Traveller

Yes, the 4WD is working fine. But this is a noise that did not exist earlier.


Disengagement on reversing (or engagement when shifting to 4H/4L from 2H) is happening as usual. Only niggle is, when in 4H/4L, the whine is there, increasing with increasing speed. And when I shift back to 2H and do not reverse to disengage ALH, the noise persists still. After reversing a few feet in 2H, the click to disengage ALH happens, and then there is no more noise.

That means you are getting the noise only in 4x4 mode.
1. Check the lubrication in the front wheels, though it is highly unlikely.
2. If the noise is coming from both wheels when in 4x4 and increases with speed, it can be axle whine due to misalignment of the front diffrential. Check if the front differential is aligned properly, it may have been slightly off due to bottoming out.
3. Finally check if there is sufficient lubricant in the front differential.

[SS-Traveller]

Originally Posted by SPIKE ARRESTOR

Don't continue driving forward after shifting from 4WD to 2WD, this is a Standard operating procedure!

Originally Posted by suman

I think he understands that very well!

Yes - one would unlock ALH in interest of FE only. Presumably there are no negatives otherwise of running on 2WD with front hubs engaged.

Originally Posted by Aroy

That means you are getting the noise only in 4x4 mode.

Nope. Only in ALH-LOCKED mode. One can choose to keep ALH in locked mode even if one operates the vehicle in 2WD.

Originally Posted by Aroy

1. Check the lubrication in the front wheels, though it is highly unlikely.
2. If the noise is coming from both wheels when in 4x4 and increases with speed, it can be axle whine due to misalignment of the front diffrential. Check if the front differential is aligned properly, it may have been slightly off due to bottoming out.
3. Finally check if there is sufficient lubricant in the front differential.

Front diff oil was changed @30k km as recommended, and I had a look myself to confirm it was properly topped up, with the recommended oil at MASS. The noise has occurred soon after.

Axle whine & front diff misalignment - never took a hit there.

Front hub lubrication - no experience with ALH, so I have no idea. The ALH units appear to have no greasing points anyway. Over to you, Spike.

Once again,

Originally Posted by SS-Traveller

Is there a lubrication issue happening somewhere?

[tsk1979]

With front hubs locked, whether 4WD or 2WD you should not cross 60kmph. So if you do not disengage do not exceed this speed.
Speaking of the Banshee, it lives in my safari also, and occasionally I also hear this whine. The service center told me its normal. So I live with it.

[SPIKE ARRESTOR]

Originally Posted by suman

I think he understands that very well!

I never denied that

Originally Posted by SS-Traveller

Yes - one would unlock ALH in interest of FE only. Presumably there are no negatives otherwise of running on 2WD with front hubs engaged.

Nope. Only in ALH-LOCKED mode. One can choose to keep ALH in locked mode even if one operates the vehicle in 2WD.

Front hub lubrication - no experience with ALH, so I have no idea. The ALH units appear to have no greasing points anyway. Over to you, Spike.

ALH needs to be lubricated every 40000 Kms, only the Drag sleeve assembly is lubricated for life. Please understand what I am trying to say- the ALH is designed to lock only when being driven in 4WD and NOT in 2WD. Yes, it is for FE, even if you do not care about FE, still you must not drive around with ALH engaged in 2WD mode, this is a wrong practice.

Lubrication details are:-

Bearing races- Light wheel Bearing grease (don't remember if it is Lithium or Graphite based)
Drag sleeve- No lubrication, it is lubricated for life.
Other components- ATF fluid.

If there is continuous noise from ALH when engaged in 4WD, then for sure it warrants inspection!

Spike

[SS-Traveller]

Originally Posted by tsk1979

With front hubs locked, whether 4WD or 2WD you should not cross 60kmph. So if you do not disengage do not exceed this speed.

Yup... knew that.

Originally Posted by SS-Traveller

...drove a few km at moderate speeds (<60km/h)...

Originally Posted by SPIKE ARRESTOR

ALH needs to be lubricated every 40000 Kms, only the Drag sleeve assembly is lubricated for life. Lubrication details are:-

Bearing races- Light wheel Bearing grease (don't remember if it is Lithium or Graphite based)
Drag sleeve- No lubrication, it is lubricated for life.
Other components- ATF fluid.

If there is continuous noise from ALH when engaged in 4WD, then for sure it warrants inspection!

Most important details! Noted this. Let's now see what my ASC does about this in the next few days (by which time, maybe, the noise would have self-healed itself...)

Originally Posted by SPIKE ARRESTOR

Please understand what I am trying to say- the ALH is designed to lock only when being driven in 4WD and NOT in 2WD. Yes, it is for FE, even if you do not care about FE, still you must not drive around with ALH engaged in 2WD mode, this is a wrong practice.

Point taken. This was the first time I did it, just to confirm the noise issue. However, Spike, would you please explain what might go wrong in an ALH when driven in locked state on 2WD? An exploded diagram of what's inside the ALH would help greatly, if you have it.

[SPIKE ARRESTOR]

Originally Posted by SS-Traveller

However, Spike, would you please explain what might go wrong in an ALH when driven in locked state on 2WD? An exploded diagram of what's inside the ALH would help greatly, if you have it.

If I have it, of course yes! What happens inside is pretty simple, but what is inside is pretty complicated stuff. Will do that tonight.

Spike

[Aroy]

Originally Posted by SS-Traveller

Front diff oil was changed @30k km as recommended, and I had a look myself to confirm it was properly topped up, with the recommended oil at MASS. The noise has occurred soon after.

Well this seems to have started the problem!
Check the level and grade of oil, could have leaked out due to loose nut.

Just and idea - your free wheeling hubs may have gone dry/dirty due to water & sand ingress.

In case you have the hubs locked in 4x2 mode, then the wheels will drive the differential and the transfer case, instead of the other way. It may also give rise to a slight whine. I have noticed this in Ambassadors when coasting down hill in neutral.

[gharika]

Originally Posted by ramkya1

Hai,

Thanks for the response. Mine has a electric switch, its in recirculation mode. Heater + Low AC is what we used in the Ladakh Run, cabin was comfortable within 5 minutes of start up. Wonder what went wrong, isn't heating up properly.

=====

The heater may not work correctly if the cable that activates the coolant flow and the air flow redirection may have problem on the knob side. So basically, when you turn the knob, the cable is not being pulled fully. I have faced this issue multiple times on my 2006 CRDe SLX. I usually fix this myself. To identify if this is the issue, you will fell the knob to be turning without any or little effort.

[SS-Traveller]

Originally Posted by SS-Traveller

Hawk-0n-Fours® started emitting a high-pitched low-intensity whine from both the front hubs when driving in 4WD (both high or low ratio). Hubs lock and unlock okay. No noise when in 2WD with hubs unlocked, but noise persists even in 2WD when hubs remain locked.

The issue was sorted out today. Mercifully not anything to do with the hub, though I admit I was a bit worried!

Originally Posted by SS-Traveller

The noise issue was surprisingly simple, and nothing to do with hubs and differentials. The front prop shaft was being scraped by an extra-long bolt on a silencer clamp, and that was all there was to it! Take a look...

Attachment 483608

Attachment 483609

Bolt turned around and fully tightened to take care of the slight silencer leak. No more noise. H-4® is back to running smooth and stable.

[booboo]

just last week on turning the steering full lock to the left (whle parking at home) the baby makes a chank-clank noise. since i had got my 60000 km servicing done just a day before i took it to the mahindra worshop to get it checked. i was told that the 'supporting bolt' was broken and since this bolt kind of prevents the tyres from reach beyond a certain position this was happening.
the bolts were not in stock so some greasing was done and the baby has been running fine ever since. just checked yesterday and the spares are still not in as yet
has anybody faced a similar problem or can the guru's advice?. the service guys swear i can ride normally and not to bother at all.
i have been doing so and have not faced the same issue after the greasing was done

[m_upreti]

Originally Posted by booboo

just last week on turning the steering full lock to the left (whle parking at home) the baby makes a chank-clank noise. since i had got my 60000 km servicing done just a day before i took it to the mahindra worshop to get it checked. i was told that the 'supporting bolt' was broken and since this bolt kind of prevents the tyres from reach beyond a certain position this was happening.
the bolts were not in stock so some greasing was done and the baby has been running fine ever since. just checked yesterday and the spares are still not in as yet
has anybody faced a similar problem or can the guru's advice?. the service guys swear i can ride normally and not to bother at all.
i have been doing so and have not faced the same issue after the greasing was done

Hi, I faced this issue when the car was run about 3000 Kms. You can hear the noise when turning a full circle. The affected part was replaced after almost 15 days of reporting as it was not in stock.

There is no issue with the ride just the irritating noise sometimes.

[booboo]

Originally Posted by m_upreti

Hi, I faced this issue when the car was run about 3000 Kms. You can hear the noise when turning a full circle. The affected part was replaced after almost 15 days of reporting as it was not in stock.

There is no issue with the ride just the irritating noise sometimes.

thanks for clarifying. but what is the problem? is it shearing off the supporting bolts (or stopper bolts i presume they were refering to)
funnily even at full turn there is no noise post greasing.