7 Speed Auto Trans Fluid Change

Tractionless

Thanks Joby (jchammond) for the laymans instructions and help via PM.

After performing the drain/fill procedure I just wanted to add a couple of notes.

1. When topping off let the car run so all of the fluid is not in the pan. I overfilled (while running), when the fluid stops pouring out of the fill plug between (100-113) pan temp. (I used a Harbor Freight Infrared Thermometer) and just begins to drip reinstall the fill plug.

2. I initially drained just 4 qts. so I added back 4 qts. during the flush and fill steps; however, for the final fill with the engine running at temp. (see above) the trans. wound up holding 5.5 qts. I therefore, recommend purchasing 4 gallons of fluid or 3 gallons plus a couple of extra qts. It's more price conscientious to just purchase the full 4 gallons though.

3. The OE drain plug crush washer is thin and after the 2nd flush and fill it looked to be leaking. I found HELP! (brand) pn# 66250 crush washer assortment contains a size that will screw onto the OE drain plug while holding it with pliers and turning the plug with the 19mm socket. Do this off of the car and make sure it's seated before installing the plug. The OE plug/washer assembly is a tight fit and the washer is actually stepped (first I've seen) to grab the threads so I wanted to make sure I had the correct contact to insure no leaks.

4. I couldn't find a crush washer for the OE fill plug and neither could the dealer. The reason the manual says to change the entire plug as the plug/washer are sold together as a unit. They're $3, so for peace of mind and for how many times you're going to be taking the fill plug in and out, I'd have one at the ready.

5. If you're going to use Valvoline Maxlife Dex/Merc. be sure to get the bottle that says "full synthetic" (in white) under the Dex/Merc. label on the front of the bottle 1/3 down. From what I found on Valvoline's website the "for 75,000 mile" designation in the same space is NOT Nissan Matic S compliant!!!

Felix 808

The problem with using an IR gun is that you are measuring surface temp, not fluid temp which can be 20-40 degs off. The best way to do it is to install a temp gauge. Then you can monitor the heat cycle of the fluid & know when you should be replacing it.

$.02

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Semper Fi

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BoneZ

I'd love to do this.

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jchammond

i used a Genisys on mine...but will be installing a temp gauge in the near future

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jchammond

ImageUploadedByTapatalk1455706970.537801.jpg
This is the fluid I used;
Meets Nissan/Infinity spec D,J,K & S


Sent from my iPhone using Tapatalk

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Tractionless

It's safe to say the fluid in the pan is transferring heat to the outside surface that the IR is reading. I watched the temp. go up as the car heated up on ramps, sitting level. I'm much more comfortable in this method than the aforementioned "back of hand on the pan" for guesstimating temp.

After all is said and done the transmission is shifting much better most likely due to being 1.5 qts. low upon drain and the fluid having 6 yrs. and 76k miles on it. My next change will be in 25k miles.

nis350

thanks for the write-up.

Have a question about fluid level.

Does it make a difference on the fluid level check with the engine running or not (in Park or Neutral)?

Has anyone heard of Liqui Moly Top Tec 1800 ATF or Eneos? I was told that both are good ATF (Matic-S) with Liqui being better (full synthetic).

Tractionless

Engine running and in park or neutral is fine.

Have you confirmed beyond word of mouth they are Matic-S compliant?

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nis350

Thanks for the info.

Yes, Matic-S is listed for both ATF. Heard the Liqui Moly is really good and it is very popular among European cars. I've used their motor oil for my M3 before. I did some research and found that many European cars use Japanese transmissions.

jchammond

If you’re using a different fluid than oem; I’d recommend to flush & ensure that you end up with what you switch over too
Wouldn’t trust mixing fluids in this pricey trans

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nis350

good suggestion. Thanks.

According to the fluid manufactures, it is fine to mix the 'matic-s compatible' fluid. I was told not to flush a high mileage transmission.

jchammond

Unsure who told you that; as it’s a hydraulic system & the fluid does break down...Some forum members remove the pan/clean while doing this process.
I’m not speaking of putting any kinda solution/cleaning stuff through it- just drain,fill,operate & repeat until fluid is nice & clean.
I’ve also heard the magnets in the pan will get pretty heavily covered.
It’s all about “PM” (preventive maintenance) & not thinking about having to purchase a $9,000.00 tranny
Or gamble on a re-Tran

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nis350

I was told not to flush high mileage trans by the dealers as well as independent technicians. I personally would not know either way, but decided just to do the drain/fill to be safe.

Saw your 'DIY' and thought that was great.

CyFi6

Just wanted to show an alternate way to fill the 7AT trans which I found to be a lot easier and less messy. There is a metal cap over what would normally be a dipstick on the right side of the trans that you can use as a fill port.

I bought some 5/8OD nylon tube from Lowes and a funnel.

Remove the 10mm bolt holding the cap in place and fit the tube into the opening from the engine bay. The 5/8OD tube is the perfect size.

Start the car up and move through the gears til you are at 104F temp on the transmission pan/fluid temp. Put it in park and leave the engine running. Remove the fill plug (make sure drain plug is installed) and place a catch pan under it. Add fluid through the funnel.

Once the trans is full it will start to come out of the fill plug and drain into the pan. At this point you can reinstall the fill plug and torque to 9 ft lbs.

Let the car cool and reinstall the "dipstick" cap.

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jchammond

You can actually put a dipstick in that hole; another form member has a setup.....seems like it’s “Tractionless” that put a kit together.
Or get a stubby dipstick tube & dipstick

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MazWorx built long block | FI-TT-100 Stage 2.75 | IPT built 7A/T

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