7 Speed Auto transmission fluid change (Skyline, Q50, Q60, Fuga, Q70, A62 Titan and probably heaps of others including Navara...)

[Duncan]

I thought I'd do a write up on an auto transmission fluid change for a the nissan 7 speed Automatic. At some stage the genius engineers decided that the fluid in the trans was "for the life of the transmission", (which seems kind of self supporting to me) and removed the dip stick and fill tube (funnily enough there is still a casting for it).

Anyway, for this job you do need 2 specialist tools in addition to regular hand tools, jack and 4 good chassis stands.

You need a way to pump fluid up to the transmission; I got one of these but there are plenty of other options:

https://www.ebay.com.au/itm/364584087070

Don't trust the generic listing though, it does not come with the required adapter for the Nissan 7 Speed.

You need one of these, can't do the job without it:

https://navarapart.com.au/product/genuine-nissan-patrol-y62-d23-np300-navara-re7-dipstick-fill-connector1

You need a heap of compatible transmission oil. Could be Nissan, could be anything else rated for Nissan Matic S. You need at least 10 litres, I had 15 to give it a better flush...

Also, you need some biiig oil catch trays, at least one of these, or bigger if possible (volume was fine, size was very marginal):

https://autobarn.com.au/ab/Autobarn-Category/Tools-%26-Garage/Specialty-Tools/Oil-Service/Garage-Tough-Oil-Drain-Pan-Black-16L---GT1068/p/TO03191

Finally, a measuring jug is very useful if your pump does not have volumes marked on it, I got a 6l one:

https://www.repco.com.au/oils-fluids/fluid-accessories/measuring-jugs/penrite-measuring-jug-6l-pmj006/p/A5322648

Oh, and gloves.....this stuff is horrible (not as bad as diff oil, but getting there)

....First, jack up your car.....

[Duncan]

So, I'm not going to cover jacking up the car in detail, as I was using a quickjack, plus it will change per chassis you are working on.

The main thing is to get the car high, level and stable, so take your time and find good spots for the stand. You are going to spend a lot of time working right under the middle of the car. If you have a hoist, or access to one, you are laughing.

First you need to remove the transmission undertray. At the rear there are 2x 14mm headed bolts to undo. Unlike (apparently) the USDM model, you can easily get at both without the exhaust being in the way. While you can undo the undertray end of the bracket on one side (2x10mm head bolts), the other side is rivetted on so you can only undo the chassis side.

At the front there are 2x 10mm headed bolts then the undertray slides backwards from under the mid tray, and out of the way.

[Duncan]

OK....now the mess starts.

At the rear of the transmission is a 17mm drain plug. Put the oil pan under and remove the plug, you should get about 3 litres of fluid out (this is the pan capacity). I forgot to take a pic of the plug, so here is a marked up one I stole. 

Drain on the left (17mm) and fill on the right (in hex)

I got about 3 litres from the drain plug, and even with 75,000klm (and 2 track days), it really looked like it needed a change.

[Duncan]

If you are going the simple route, this is all you need to do on the draining side.

Just keep in mind that you are only replacing 30% of the fluid with each "spill and fill" - 3 litres in and the workshop manual says system capacity is 10 litres, and it recommends doing it 3 times.

I can't do maths but chatgpt tells me it can, this is what % new fluid you have after each 3 litre flush:

So you can see, you need 20 litres+ and 7 cycles if you want to get to 90%+ new fluid in the trans....slow and expensive!