Hi and Help please.

[jpd]

Hi there. I'd like to introduce myself and participate in your forum and hopefully be able to give a little knowledge back.

My name is Jeff and last June I bought a MY 18 NX Pajero GLS for the purpose of towing a bigger caravan. Our current van is a tandem axle 20 ft poptop which has been towed by a Holden Adventra for the last 8 years. We'd like to upgrade to a semi - offroad full 'van hence a beefier tug was needed.

All seems to be going swimmingly except for this vibration that's driving me crazy. I've done a lot of googling and reading through the wealth of knowledge in a lot of similar threads on this forum but no-one seems to have exactly the same syptoms. I'd be very grateful if any of the learned members with a late model NX here could chime in with any input please.

It is an ex MMAL fleet car from MM dealer in Sydney. I bought it with 6600 km's on it and now has 13100 km's. 1st registered in January 2019.

Symptoms are;
1800 - 2100 rpm in 4th of 5th with the lockup clutch in the Torque convertor engaged. The harder you squeeze the throttle the worse it gets untils the LUC is released and all ticketty boo.
You can feel it in the steering wheel and a little in the accelerator pedal.
At freeway speeds (100-110kms/hr) it gets that bad that it distorts the view in the rear view mirror.
It doesn't feel like Damper clutch "judder" as in the old magnas or diff shudder in the NH/NG pajeros when new.
It won't do it in neutral or reverse.
It's not vehicle speed related.
Lift your foot a tad and it goes away until its time to accelerate again.

I've had it back to the local MM dealer a few times and keep getting told it's the nature of the beast. Even the area technical officer stated it was normal but he hadn't actually driven my car. To my knowledge it's not even been put up on a hoist for a look see at mounts etc. I fail to believe that a model can be around this long and still have a significant inherrent problem like this.

My background is in fact a mechanic/foreman/service advisor with 20 years in MM service departments but I left that behind 20 years ago to pursue a decent payrate elsewhere. I was in fact one of the 1st MM master technicians in OZ so maybe you can understand my frustration at not thinking this is "normal" for the beast.

Apologies for the long winded intro but maybe some learned members here have had a similar problem on a late NX.
Thanks for reading, cheers Jeff

[nj swb]

Hi Jeff, welcome to the forum.

Long post? That's nothing!

Your experience of vibration and being told "that's normal" is becoming all too familiar. One of our members has a sophisticated vibration analysis app for his iphone that has reported his vibration is 2nd order engine harmonics - but he's only experiencing the problem in 4H, and it doesn't appear to relate to the lockup clutch. When you experience this problem are you driving in 2H or 4H? Does it make a difference?

For reasons I can't really explain, I'm wondering if Mitsubishi have made a change to the engine mounts. Feeding my VIN into Partsouq I get one part number back for engine mounts. When I drill down through the menus to a 2018 Australian spec Exceed, I get three different part numbers. Who knows if this is significant?

Other info that may or may not be relevant:

When I bought my NT it was in Brisbane, so I drove it back to Adelaide. I noticed at highway speeds, on cruise control with the torque converter locked, as the vehicle hit a rise I'd get a brief period of shudder (felt a little like misfiring) then the torque converter would unlock and all was good. When I reported this to Mitsubishi in Adelaide they performed a software upgrade that made the problem go away. Programming of the lockup clutch can affect vibration in the car.

Vibration under high load with a locked torque converter isn't unfamiliar to those who run an aftermarket lockup kit, but in my experience unpleasant vibration (due to override of the lockup) normally only occurs at lower engine speeds than you're reporting.

It appears newer models have more of a vibration problem than older models - so what's changed? Two changes that come to mind are the reintroduction of the DPF (late 2016, for MY17), and slightly taller diffs that came with it. Is the extra mass of the DPF in the exhaust affecting vibration patterns some how? The taller diffs have added a small amount of additional load to the engine for any given combination of gradient / road speed. Is this contributing to the apparent inappropriate use of lockup? Did Mitsubishi change the programming to keep the converter locked at the same speeds / lower revs with the taller diffs?

On the subject of lockup programming, forum member m_and_m designed and developed the MM 4x4 auto-mate, which I rate as the most sophisticated aftermarket lockup product available. If your issue is solely because the lockup isn't hanging on under too high a load then he might also be able to provide some useful information.

Last, the Jatco transmissions in the Gen 3 can start playing up with old / dirty transmission fluid, or incorrect spec fluid. Your vehicle doesn't have the Jatco, it should be too young/new for fluid problems to have developed, and your transmission isn't as sensitive to transmission fluid even if somebody had performed a change. So the idea that transmission fluid could be your problem is a long shot, one that you shouldn't need to explore while the vehicle is under warranty, and without a transmission dipstick, it's difficult to check fluid condition anyway.

It sounds like you have a real issue, and Mitsubishi are not going to help you fix it - not without a lot of prodding. It might help your case if you can obtain an OBDII monitor of some description, and use it to keep an eye on boost / engine load / revs / perhaps transmission temps? If you can define a combination of conditions that create the vibration and enough of us don't have the same vibration under the same conditions perhaps you'll be able to find somebody at Mitsubishi to pay attention?

[jpd]

Many thanks for the reply and info. I feel i'm in the right place for problem solving. In reply loosely.
I haven't tried it in 4H as by memory 100km/hr is the suggested limit.
It does feel like an engine mount but why so much vibe with the LUC on. It's pretty smooth (for a diesel) when not on. I do remember old sigmas the engine mounts sagged after time and they vibrated on acceleration so maybe a look at the crash shields maybe worth a look.
The only thing the dealer has done is re-flash the LUC program and apparently adjusted it but it made negligible difference if any. On that note I'm getting fairly respectable fuel consumption of an average of 9.5 but more about that another time.
Yes I have walked up to other older NX owners and asked them if they experience my problem and they say negative so you may have something there about what have they changed??.
Good info about the gear from m_and_m and will keep it in mind but while its still in warranty I'd like MMAL to get this fixed 1st (if possible).
It's my understanding that these have an Aisan - Warner box similar to a Prado (so I'm told) and they apparently don't have a problem.
Yes I agree that it may not be oil quality/spec related especially at only 6600 kms when I bought it. The problem with that is yes I took it for a test drive around suburban Sydney before I bought it but only got to 70kms/hr. I noticed it as soon as I hit the freeway home on the 1st day.
Having said that it wouldn't be the 1st time that a manufacturer has had the wrong spec oil supplied at factory build. I don't mind paying for an oil change for the experiment but not without further input.
Also it doesn't seem to do it when cold as with the older cars the LUC doesn't work until the ATX oil is warm enough (Think Magnas)

God, even my reply is long winded

[nj swb]

Yep, same Aisin transmission as the Toyota A750F.

I believe it is something Mitsubishi has done in the last 3-5 years, as vibration issues seem to mainly be with newer vehicles - mainly NX?

When the transmission oil is very hot it will overflow if you remove the overflow plug - might be a relatively simple way to check fluid condition?

[skins2380]

G'day Jeff & welcome.

Have a look at this link it sounds a bit familiar yo your issues; https://www.carbibles.com/torque-converter-problems/

and by the way I am no mechanic. I did see on another site (think it was whirlpool) of another bloke with an earlier model Pajero that had similar issue to you, he reckoned it was his TC also. Got the tranny fluid changed and problem went away for about 10,000ks & then returned, so he got his TC replaced after a lot of arguing with the dealership and problem fixed - 100,00ks later & still going strong.

[jpd]

Yep, same Aisin transmission as the Toyota A750F.

I believe it is something Mitsubishi has done in the last 3-5 years, as vibration issues seem to mainly be with newer vehicles - mainly NX?

When the transmission oil is very hot it will overflow if you remove the overflow plug - might be a relatively simple way to check fluid condition?

Thanks for the info again and what ever happened to good ol' dipsticks??

[nj swb]

Thanks for the info again and what ever happened to good ol' dipsticks??

They shrink over time and no longer reach the oil, so you need to buy a longer one.

[jpd]

G'day Jeff & welcome.

Have a look at this link it sounds a bit familiar yo your issues; https://www.carbibles.com/torque-converter-problems/

and by the way I am no mechanic. I did see on another site (think it was whirlpool) of another bloke with an earlier model Pajero that had similar issue to you, he reckoned it was his TC also. Got the tranny fluid changed and problem went away for about 10,000ks & then returned, so he got his TC replaced after a lot of arguing with the dealership and problem fixed - 100,00ks later & still going strong.

Thanks for the input and I'll try whirlpool. Wouldn't it be great if it was just an oilchange but at so low km's I'm not holding my breath.

[jpd]

They shrink over time and no longer reach the oil, so you need to buy a longer one.

[old Jack]

Hi JPD,

Have a read of this thread;

https://www2.pajeroclub.com.au/forum/showthread.php?t=64301

I do not think Mitsubishi can fix the problem unless a cause is clearly identified.
My belief is it is likely to be a combination of many things including the change in diff ratios and the automatic transmission torque convertor lockup program.
Wheel alignment, tyre pressures, tyre tread pattern and wear, tailshaft phasing could also contribute to the problem.

It appears the monocoque design of the Gen 3/4 Pajero is very sensitive to harmonics and vibrations, Mitsubishi have gone to significant lengths to try a minimise these harmonics, there is a large vibration dampener fitted on the side of the transmission and another 2 dampners on the rear suspension. You could try removing 1, 2 or even all 3 to see what effect these have.

OJ.

[Keithyv]

I'm pretty sure there's no limit to the speed you can do in 4H.

I'd be guessing diff ratios may be the difference?
Certainly in my NW I only get a hint of what is being described here and that is when the lockup-mate is locked and I'm lugging along 'too slow' for the given gear.

This generally only happens for a few seconds at most and then the TC lockup dis-engages.

[farcanal]

Hi there. I'd like to introduce myself and participate in your forum and hopefully be able to give a little knowledge back.

My name is Jeff and last June I bought a MY 18 NX Pajero GLS for the purpose of towing a bigger caravan. Our current van is a tandem axle 20 ft poptop which has been towed by a Holden Adventra for the last 8 years. We'd like to upgrade to a semi - offroad full 'van hence a beefier tug was needed.

All seems to be going swimmingly except for this vibration that's driving me crazy. I've done a lot of googling and reading through the wealth of knowledge in a lot of similar threads on this forum but no-one seems to have exactly the same syptoms. I'd be very grateful if any of the learned members with a late model NX here could chime in with any input please.

It is an ex MMAL fleet car from MM dealer in Sydney. I bought it with 6600 km's on it and now has 13100 km's. 1st registered in January 2019.

Symptoms are;
1800 - 2100 rpm in 4th of 5th with the lockup clutch in the Torque convertor engaged. The harder you squeeze the throttle the worse it gets untils the LUC is released and all ticketty boo.
You can feel it in the steering wheel and a little in the accelerator pedal.
At freeway speeds (100-110kms/hr) it gets that bad that it distorts the view in the rear view mirror.
It doesn't feel like Damper clutch "judder" as in the old magnas or diff shudder in the NH/NG pajeros when new.
It won't do it in neutral or reverse.
It's not vehicle speed related.
Lift your foot a tad and it goes away until its time to accelerate again.

I've had it back to the local MM dealer a few times and keep getting told it's the nature of the beast. Even the area technical officer stated it was normal but he hadn't actually driven my car. To my knowledge it's not even been put up on a hoist for a look see at mounts etc. I fail to believe that a model can be around this long and still have a significant inherrent problem like this.

My background is in fact a mechanic/foreman/service advisor with 20 years in MM service departments but I left that behind 20 years ago to pursue a decent payrate elsewhere. I was in fact one of the 1st MM master technicians in OZ so maybe you can understand my frustration at not thinking this is "normal" for the beast.

Apologies for the long winded intro but maybe some learned members here have had a similar problem on a late NX.
Thanks for reading, cheers Jeff

For Mitsubishi to say "that's just the nature of the beast " is just plain wrong.
I can remember the shuddering in automatic Magnas ( I was a small country dealer) and they were all fixed, even out of warranty.
Don't give up on them...THEIR problem to fix, not yours.

[BOGWHEEL]

My new NX doesn't like top gear at 100km/h - feels like it's labouring. If I increase to over 105km/h it smooths out. (even more so with cruise control set)

In 4H it is considerably worse - even seat belt adjusters are rattling - will not be towing in 4H.

[Mundy55]

I can't help but think some of these issues must be due to differing tyres, suspension, loadings and perhaps, personal sensitivity. I don't seem to have any of the vibration or rattle issues described by some owners, so it can't be an inherent issue, can it?

I drive in 4H all the time. I tow a camper. I do highway speeds up to 110kph (actual). I drop down into 2H from time to time to exercise the change mechanism. I have had BFG KO2s since new (done 99k km so far). No issues before or after 40mm suspension lift. Normal driving weight is about 2.7T (rear drawers, water tank, bigger fuel tank etc). But no bull bar or winch.

Love the car overall but dislike the headunit and the inadequate noise attenuation.

[jpd]

Thanks people for the input so far.

Just to re-iterate my NX is bog standard. No lift kits, original tyres and rims, no skinz accessories. All it has is MM alloy nudge bar and towbar.

Apologies to @Keithyv as I misread the little card and there is no recommended top speed limit for 4H only advice that shifting from 2H to 4H is recommended to be under 100km/h.

So to me there is these main thoughts for me to follow up;

I'll remove the dampers one by one and see if it makes a difference.

If nothing changes with that I'll try an oil change with The proper MMAL oil and re-evaluate for any change at all to see if we're heading in the right direction.

If I can get it on a hoist I'll see if I can see anything around the engine and transmission mounts.

Interesting thing is though we've had no one else with a late model NX chime in yet to see if mine is the only late NX with this problem. It does seem plausible that there was a line in the sand when MM changed specs (diffs etc) that the vibe may have started from there on.

I'll keep chipping away at MMAL though.