Navara D40, auto transmission very nervous, drivetrain vibrating!!

We have done 8K km the last few weeks with no problems (apart from a breakdown within first 85 km), but since crossing Nullabor transmission is very nervous.
Would it be a manual I‘d say clutch is slipping, but it feels a bit different.

Around rev of 2.200 needle and sound goes up and down (like changing half gears) not much power on wheels. But what worries me most are fast back and forth movements (like shaking vibrations) on the drivetrain.

My better half was driving some km on sealed roads forgetting to switch back from 4x4 (and she likes driving fast). Since than we are experiencing difficulties getting back in 2x2.

Can there be a connection?
Your help is very much appreciated as it is quite hard getting informations here in Lucky Bay, WA

Nissan Navara, D40, 2010, Diesel
148.000 km
Radiator (engine and transmission) got changed 8.000 km ago
 

jazzeddie1234

Well-Known Member
May 19, 2016
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If you are mechanically minded I would suggest:
check for computer fault codes (some codes do not trip the check engine light at first)
check auto trans fluid level - some have dipstick, others you get under and remove the fill bolt. Also put some on clean white paper and check/smell for any sign of burnt or colour variation
check the free play on the driveshaft slip joint where it enters the transfer case (push hard up and down) some play ok but should not be loose
drop driveshaft and check front universal joint for stiffness or rough movements

the rev changing thing could just be the torque converter doing it's normal thing when you apply power or a sensor, or fluid levels...
difficulties going into 2wd/4wd could be a sensor, the electrical control plugs/sockets (try unplug and replug), low oil in the shift on the fly (if you have it) the front diff can have 2 fill points and the second one gets overlooked - takes 100mll (ish) to lube the front engagement mechanism

good luck
 
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jazzeddie1234

Well-Known Member
May 19, 2016
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Mandurah
Then I suggest you ask around for a 4wd repair shop (go to a few 4wd accessory stores and ask) as you may find a regular repair shop or dealer has little idea/interest. A specialist auto trans shop may give you some free advice. Also try the 4wdaction forum - plenty of knowledgeable people there
 
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I went all the way to Albany (500 km from Lucky Bay) to see a transmission specialist:

Checked the transmission and the "clutch" but didn't find anything abnormal.
Oil was still good, not burned, not black so no sign of anything nasty in the gearbox.
No fault codes, no errors
Got a second-hand throttle control unit to see if mine is faulty, but didn't do any change.

The specialists believes that there is somewhere a part that is causing slight troubles but still not strong enough to send Errors and fault codes to the diagnose.
He thinks the engine control lamp will go on in a few 100 km. Might be the EGR or anything related to it.
Well, wasn't as expensive as I thought, but still didn't solve the problem ;-(
 

Drover

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Nov 7, 2013
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Possibly the transfer case could be bound up a little bit due to operating in 4WD on hard surface, not sure if the Nissan has a geared or chain driven unit, may loosen up in time.....try reversing a little when engaging and disengaging 4WD, never use on hard surface, you may destroy the TC and that's it, stopped dead in water.
 

Drover

Well-Known Member
Nov 7, 2013
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That might be the best way to go, so long as the oil is clean and filters got changed, use it in manual when it has to work so it stays cooler should be able to last the distance ................. otherwise I hope you are having fun besides the mechanical headaches.
 
Yes, we are having fun and even my kids are enjoying it ;-). Australia is fascinating and there is something brilliant just around almost every corner. We’ll, in WA those corners are a bit further apart ;-).

Yeah, we try to be nice to our gearbox, have full service ever 10K and we are confident it will last till we are back in Sydney again. But before we‘ll pay you @Drover a visit anyway
 
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