Transfer case failure

[SWB ANDY]

evening

looking at the first couple of photos, I have never seen the internals of a transfer case, but from what I can see in the photos is that the gear directly below the damaged one has what looks like no damage to it.
I can only assume that these 2 gears mesh together, so if one has damage surely they will both be damaged???
to me it looks as though the bearing has been running loose (as already mentioned) for some time, wether it is an optical illusion, the damage on the teeth looks to be aluminium melted to them.
so I think that as a result of the bearing not seated correctly that this has been going on for a while and any play from the bearing has then caused the gear to chew away at the casing from the inside until eventually the inevitable happened, I don't think that the locker had anything to do with the damage. I am by no means an expert just going off what I can see, hopefully some one more knowledgeable will correct me.
I hope it all goes well for you with Mitsubishi and that it is not too expensive to fix.
good luck
andy

[4wd26]

do you run a auto locker or a manual (air locker?)

their have been some cases where the transfer chain has stretched and caused some damage

[Morville]

Sounds like a classic case of was the chicken or the egg, which was first. Should the front diff be checked for damage too, seeing there is damage both sides of it?
Peter

[nj swb]

I called in at Mitsubishi today, and they showed me the disassembled transfer case. Unfortunately I have no pictures, but the opposite side of the gear in the pictures is missing about 5 teeth - broken off at the root.

That's exactly the same scenario as the event I witnessed in Queensland, on the June long weekend in 2004 - a near new NP, IIRC. Anybody here from the Mitsubishi 4wd Club of Queensland?

[macca1]

I called in at Mitsubishi today, and they showed me the disassembled transfer case. Unfortunately I have no pictures, but the opposite side of the gear in the pictures is missing about 5 teeth - broken off at the root.

That's exactly the same scenario as the event I witnessed in Queensland, on the June long weekend in 2004 - a near new NP, IIRC. Anybody here from the Mitsubishi 4wd Club of Queensland?

My experience with teeth broken out at the root indicates shock loading somewhere, maybe during the failure of the CV.
Just another thought.
Ps; ask an engineer typical tooth failure reasons.

Macca

[geopaj]

I called in at Mitsubishi today, and they showed me the disassembled transfer case. Unfortunately I have no pictures, but the opposite side of the gear in the pictures is missing about 5 teeth - broken off at the root.

That's exactly the same scenario as the event I witnessed in Queensland, on the June long weekend in 2004 - a near new NP, IIRC. Anybody here from the Mitsubishi 4wd Club of Queensland?

Any update on how it's going with the dealer?

[letsgoplaces]

Any update on how it's going with the dealer?

x2 I've been thinking the same thing

[nj swb]

I called in last week to drop off the broken tooth brought home by m_and_m, and I felt the reception was a little on the frosty side - so I thought I'd leave them in peace for a little while.

It's now been over a week, so I guess its time to chase them up about it.

[letsgoplaces]

It will be interesting to see if they've even looked at it

[Bogger]

For what it's worth from what I can see from damaged teeth this hasn't happened or begun at the point of failure in that the wear I can see shows wear over time. I think the other day was simply what broke it's back.
It looks like there has been a foreign object in box and would say that it has finally lodged between the two gears which being a very close tolerance mesh can only make room for the "new bit" by one way and that is to separate the two gears. I think it's this force that has then basically pushed the output shaft out the side of the housing as it had to go somewhere.
An instant failure would show very sharp in fact sharp enough edges to cut your finger on where as what I see is the edges are rolled smoothed which comes from running after being broken / chipped (like gemstones in a tumbler become smooth)
Pretty sure your looking at the result of and not the cause. Problem for me lies deeper in transfer. Even sloppy shift and dropping out of mesh under load could have chipped a tooth to start and it has been this piece that has found it's way between the two teeth or a complete foreign body.
Good part is as it's catastrophic then whole transfer will be replaced so original cause will go with it also and won't rare it's head again.

See pic how edges of all breaks are smooth not sharp ............. only comes with use after the fact. You can also see in second pic marked blue areas that show damage to teeth right across face of gear tooth ........... as said something has been amiss for many K's before actual failure. I'm actually surprised that they haven't pointed this out to you ? But then it is a dealership with the typical to many in white shirts and not enough hands on people involved.
Don't be to harsh on Mitsu if they knock it back as warranty ................. I know this is not what you want to hear just being honest but also fair. If they honor it then I'd say you've had a lotto win.

[nj swb]

It will be interesting to see if they've even looked at it

As posted earlier, they've disassembled the case and found 5 teeth snapped off the gear visible in the photos. I haven't heard anything since that visit.

Pretty sure your looking at the result of and not the cause. Problem for me lies deeper in transfer. Even sloppy shift and dropping out of mesh under load could have chipped a tooth to start and it has been this piece that has found it's way between the two teeth or a complete foreign body.

I agree. I don't believe this much damage was caused in the aftermath of a CV breaking, either. Something failed inside the transfer case.

Don't be to harsh on Mitsu if they knock it back as warranty ................. I know this is not what you want to hear just being honest but also fair.

I fully accept that it's not strictly covered by warranty, but I don't accept that this is a reasonable failure to accept on a 6 year old vehicle with 42,000km on the odometer. I'm happy to be fair, I'm willing to contribute to costs, but I have asked Mitsubishi to contribute too - if the original owner hadn't passed away, and still owned the vehicle, it would be a warranty claim.

Hard driven Pajeros break CVs, axles and drive shafts - they don't break transfer cases after 42,000km. Before this incident, I've never broken anything in a drive train - I don't drive that hard.

I have heard of low range gears failing in an NP transfer case, which Mitsubishi replaced under warranty with no questions asked - presumably, they chalked that up to a manufacturing defect.

I believe this is the same failure.

[Bogger]

Don't shoot me I'm only the messenger
I agree with you at 42000 I'd not be a happy camper.
Yes could well be a defect has caused the problem .......... even a dislodged circlip that has let a gear float could have caused the initial start of the prob.
What ever for my money it should be repaired simply out of goodwill as lets be honest a few thousand to a working man is a lot of money to Mitsu Motors they would spend more on a staff morning tea. Problem is they just spend more time ducking and weaving than it would take to get the job done and vehicle back on the road.
Hope you win with it.

[nj swb]

What ever for my money it should be repaired simply out of goodwill

That's what I'm hoping for - a goodwill gesture to help with an extremely unusual failure.

Hope you win with it.

Thanks.

[letsgoplaces]

As posted earlier, they've disassembled the case and found 5 teeth snapped off the gear visible in the photos. I haven't heard anything since that visit.

Oops, that's what I meant. I wonder if they've looked at it since the initial inspection.
With the size of the job to be carried out and the need for new parts, I would have expected a call to say what parts are needed and do you authorise the repair. Maybe?

[nj swb]

Oops, that's what I meant. I wonder if they've looked at it since the initial inspection.
With the size of the job to be carried out and the need for new parts, I would have expected a call to say what parts are needed and do you authorise the repair. Maybe?

Sorry John.

Their initial inspection claimed it was the failure of the CV due to abuse that triggered the failure in the transfer case, and they gave me a quote to repair it all. At that stage, they hadn't disassembled the transfer case.

I explained that I didn't accept that explanation, along with some reasons for why, and that I wanted to ask Mitsubishi to contribute to the repair. That's when they agreed to remove & disassemble the transfer, and they haven't called me since.

Last week, a representative of Mitsubishi's SA office was due to visit the dealer (for other reasons - not to see my transfer case) and the Service Manager intended to discuss the issue with him. He also stated that he would send my request for assistance "up the line", which is entirely reasonable - this isn't a decision for the dealer to make.

I didn't expect anything to happen quickly, but it would be nice to receive an occasional update. Having said that, I had to wait in the Service Reception while another customer had a long-winded whinge about EGRs and inlet manifold blockages, so I understand that the Service Department does have other things to deal with...