Pajero occasional noise and vibration

[rroker]

Hello friends,

My Mitsubishi Pajero 3.5, LWB, 2017 makes an occasional noise and vibration which usually starts at lower speed, increases when I slow down and completely stops with a shudder when I brake. The sound is like the racing of a high speed car or motorcycle.

You can hear the sound in this recorded video:

https://youtu.be/a8v9BJ-X8eY?si=mrLyw4T7mBbBf-K3

I intentionally did not come to a complete stop while recording this video so that I can have a longer recording of the noise. At the end of the video, I come to a complete stop and the noise stops. (1:20)

I have been to 3 garages including Al Habtoor but all of them ask me to recreate the sound during a test drive which is impossible to do as I have been unable to establish any correlation between the sound and any specific usage of the car.

Yesterday I got my timing belt replaced by Al Habtoor and they had told me that maybe the sound would go away after that but lo and behold it occurred within 5 minutes of me taking the car out of their workshop.

The following jobs were done on the car as a part of maintenance or service which did not fix the noise:

• All Disc skimming
• Front brake pad replacement
• Engine oil, filter replacement
• Steering column boot lubrication
• Brake cleaning
• All 4 tyres replaced (HT to AT)
• Wheel balancing and alignment

These jobs were done over period of few months. None of these jobs fixed the noise problem. Also I have been on 3 newbie offroad drives but the problem has never occurred during off-roading.

Apologies for the long post, I had to make sure I provide all the details because I am at my wit's end here. I will be going back to Al Habtoor but it would great if an experienced Carnity member can guide me in the right direction of what this noise could be.

Thank you!

[Srikumar]

The noise feels like a rubbing noise or from the wheel bearing.

Just check if the mud guards are not scrapping the tyre especially in the front. Do you have a skid plate for the front bumper? Reason I am asking is because the Pajero front bumper without a skid plate does tend to bend inside after a couple of off-road drives.

See if you can get someone to sit with you and try to find out from which side of the car the noise is coming from. That might help to identify if it's a wheel bearing issue

[Islam Soliman]

Hi @rroker.. I think they need to isoline first if noise is there while car is  on “P” and play with engine to get it to higher RPM, if it is still there then this isolates all moving parts on wheels, brakes, suspension, and transmission and focus on engine and other moving parts like belts, rollers, or engine it self.

if noise is not coming on that state then with extreme cautions and proper safety preparations they can put the cat on the lift to just barely take the wheels off the ground (few centimeters) and ensure the car is stable and then engage transmission and start accelerating to simulate the issue and identify where it’s coming from.. highest suspects will be wheel bearing, drive shaft, transfer case, or transmission itself. 
P.S. that last test need to be done by a very experienced person who ensures the car is fully stabilized on the lift before they engage the gear and will not change with vibrations once it’s engaged 

[Gaurav]

It's 90% wheel bearing and the best part is, it will get worse progressively very soon.

Ask a mechanic or DIY, jack up one front tire off the ground and check the wheel for two levels of play: Up and down and then side-by-side. Any play is not acceptable and you need to change that side wheel bearing. 

Do the same test on other front side and you will find the culprit easily.

 

[rroker]

Thank you for the detailed replies @Srikumar, @Islam Soliman and @Gaurav.

@Srikumar I do not think it is the sound of rubbing, not sure about wheel bearing sound though.

I do not have the front skid plate installed and after every offroad drive the tyre did start slightly touching the front back bumper at certain angles but I got it fixed each time. This noise problem existed before my first ever offroad drive, (which was with you @Srikumar BTW ) so it seems unrelated.

From the driver's seat, the noise does not seem to be coming from left or right, but almost center.

Heeding advice from you guys, I decided to visit my garage today and luckily the noise started when I was about to reach the garage. I called the mechanic out on the road and was able to demonstrate the noise to him while slowly driving past him. Later we put the car on a lift and tried spinning the wheels in 2H and 4H. The mechanic concluded that the noise is not related to the wheel bearings but he pointed to the front differential and said the noise seems to be coming from there. Also he pointed to fluid leaking from the differential. I have taken a picture of the part that he suggested to be faulty:

 

After leaving the garage, I got the noise again. I tried switching from 2H to 4H and the noise just went off when the car switched to 4H. As I had mentioned before, the noise problem never occurred while off-roading when I was always in 4H.

Googling for "Pajero front differential issues", found me some posts on various off-roading forums that had people complaining about the exact same symptoms as me. The final solution was replacement of either solenoids, actuators or both.

I am going to get a second opinion about the wheel bearings and front diff from Al Habtoor before getting anything fixed. Would also appreciate any further comments from you guys. 

 

[Islam Soliman]

Hi @rroker..that is good progress. If there is oil leak in the front diff why they didn’t check the oil levels across all transmission system.. must be low and could be also overdue for change which can cause such noise. I would do that before jumping to parts replacement

[Marek]

and THAT is something they were not able to identify at al habtoor? I mean - have they even looked under the car?

does every driver in this country need to be a mechanic in order to have a reliable car?

[Gaurav]

Good find, finally.

However front diff grinding due to low oil will be constant and not intermittent.

Still double check the wheel bearing, as wheel bearing noise starts with intermittent behaviour then become all time feature if you ignore.

[Marek]

front diff grinding sound can be caused by half-locked solenoid... so he's onto something. Nonetheless the leak is also something to address (and fast) regardless of the root cause of the problem there...

[Frederic]

28 minutes ago, Marek said:

front diff grinding sound can be caused by half-locked solenoid... so he's onto something. Nonetheless the leak is also something to address (and fast) regardless of the root cause of the problem there...

I was thinking the same about the half-locked solenoid or actuator, but in that case it would keep showing the blinking 4x4 lights on the dash i presume ?

Another thing that's bugging me is that in 2H the freewheeling clutch disconnects the front drive shaft, so the diff should not be rotating or causing noises in 2H, or am i also wrong here and there is still some kind of connection on one wheel ?