Drain/Fills are the best way to exchange fluids. Helps a lot that Nissan now uses the same fluid for the transmission and power steering, you can drain and fill your brake fluid as well which will help but the brake system will require an actual flush. Be aware that symptoms of slip might not be remedied by a drain and fill. Sure it can help with some vehicles however don't place all your hopes on this.

One of the things you should do is buy a BT OBD scanner to monitor your trans temperatures while it's slipping and then after the fluid change. Good luck!

 

Love VIR. I work the events as a Marshall/flagger. Fun to watch these cars compete. ESP seeing a g37 coupe out there. I’ve got an 11 g37 coupe - shadow graphite

 

Hello Everyone! It has almost been 7 years since I created this thread. Over the years many of you have contributed new ideas, references and improvements. That is fantastic! Thank you all for coming together like that!

I wanted to let everyone know that I still own my G37. Currently at just over 70K miles it works flawlessly. The transmission shifts impeccably. It is still as joyful to drive as when it was brand new. Below is a quick summary of ATF transmission fills performed.

Sep 2014 -- 15,483 miles -- Matic-S, transmission fluid flush by dealer.
May 2015 -- 21,765 miles -- Amsoil Signature Series Fuel-Efficient Synthetic ATF (ATL product code)
July 2017 -- 41,005 miles to present -- Pennzoil Platinum LV Multi-Vehicle ATF Full Synthetic

Happy driving! All the best to all of you!

 

Does anyone know the fill plug part #. I can't get mine out, I will have to drop the pan and try to get it out. but will need a new one.

thanks,

 

Here you go... from discountinfinitiparts.com as of 30 October 2022:

 

isn't that the drain plug? I need the other plug where you put the fluid back in!! and I can't find the part even listed or shows on any parts website! it looks more like this:

 

My bad. Total brain fart there- too much Halloween candy/ Reese cups, perhaps.

That said, the "plug" is universal in that it goes by several different names depending on the part it is used on. It can go by "Trans Drain Plug," "Diff Drain Plug," or "Trans Case Drain Plug-" again, depending on year, model, and usage.

Anyway, here you go- from Concept Z- the part is available from Infiniti but this site had a picture (as of 30 Oct 2022):

Sorry for the confusion...

 

After searching the whole internet for 6 hours, I think I finally found it.

part # 31361-1XJ0A

 

Best advice, I would suggest you email discountinfinitiparts.com with your VIN and have them verify which plug you need for the 7AT. They are a actual dealership and offer top-notch customer service. They will tell you exactly what you need.

Good luck!

 

you my hero!

 

just double check that this is what you are really looking for and it's the right part.

 

Hello all. I read through this whole page couple times and have couple questions.

I purchased my G37 when it had 74k miles and now it has 141k miles.

Vehicle is already on ramps and I drained ATF. What's interesting is after engine was warm, vehicle off, I drained through Fill plug first and 1.5 quarts came out. Isn't it too much from FILL?

All together drained was about 4.5

My final question, since it says here that it is "better overfill than under-fill", since fluid expands when hot, wouldn't it be better to just add to "proper level" when the engine and transmission is cold? When its warm, it should't expand by that much, right?

 

Hi.

The full/correct level is achieved with the engine running and ATF circulating through the transmission. If you turn the engine off and use the fill point as the depth/level gauge for the ATF level then you will not have enough fluid in the system. Infiniti recommend you get the transmission oil to a certain temp (can't remember what it is 70F maybe) with the engine running and remove the fill plug to allow any access to drain out. Once the flow stops replace the full plug and you're at the correct level here.

An alternative option is with engine off/cold, is to drain what's in the transmission pan. Measure this and replace the volume you drained cold, with fresh equivalent new ATF volume. No need to mess around with running engines/temp guns etc this way. (assuming the trans level was good in the first place! lol!).

My G37 trans hadn't been serviced and apart from dark fluid, was in good condition. I now have a q50 and changed the ATF on this not too long ago. The trans slips, so I may add additives to help it out as it annoys me! lol! Same trans I belive.

Good luck.

 

Thanks for response, I am still confused though, pan was at about 92F, engine off, why did it drain 1.5 quarts from FILL plug? I read several posts here of people following correct fill and drain procedure, but after installing dipsticks saw that their levels were low.

So that's what I am wondering still, if you fill it like service bulletin says, but with engine cold, by how much would oil expand? If it will expand only by like .5 quarts, maybe its not a bad idea that way as slight overfill is better than slight underfill.

 

Hi there. The answer in my first sentence:

"The full/correct level is achieved with the engine running and ATF circulating through the transmission."

The torque convertor is a huge reserve of fluid in these systems. When the engine is not running, some of the ATF fluid will drain back from the torque convertor to the pan, and thus why you see 1.5 litres of "extra" fluid draining from your drain point.... So, the engine must be running, and ATF pumping around the full transmission + torque convertor for you to monitor the correct level in the transmission sump.

The ATF fluid thermal expansion properties aren't going to increase hugely in volume as it warms so I wouldn't worry about that so much. Your key factor here to not screwing up your tranny is to set the fluid drain level with the engine running! Once your fluid stops overflowing with the engine running, you can add a little more ATF if you wish to make sure you're topped off.