2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

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imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby imnprsd » Wed Jan 05, 2022 3:32 am

Nissan and Infiniti build great transmissions back in the GEN-1 days, but reading that dipstick is not straight forward. And my efforts to figure it all out led me to these conclusions which I hope help you DIY or when talking to your mechanic to do a transmission flush in your FX45 or FX35.

For a complete summary, you can download the attached .pdf located on this other Infiniti Forum website that allows me to attached a .pdf, because this NICO Club Forum does not let me attach .pdf files, which is too bad.

GO TO ==> https://www.infinitifx.org/threads/2004 ... ure.37572/

SUMMARY & NOTES:

I found no issues using Valvoline Max Life ATF (Full Synthetic) in place of Nissan's Matic "J" and you can order this stuff for $18/gallon on Amazon with free delivery. That's 1/4 the price of Nissan's Matic "J" fluid at $18/qt.

However, the real value of this thread is knowing how easy it is to flush your entire transmission fluid out... without mixing the new ATF with the old ATF.

Also, IMO, I would not bother changing the metal filter screen since it's not a paper element and this makes the whole procedure easier and faster.

The secret to a complete ATF service is to pull the transmission cooler return line; while you start-and-stop your engine; 3 qts at a time; and then learning how to read your dipstick at normal operating temperature; instead of at 149F, which none of us can due without an expensive scan tool.

I hope the attached .pdf linked below helps you get not only better performance out of your FX, but hopefully better MPG around town!

https://www.infinitifx.org/threads/2004 ... ure.37572/
Attachments
2004 FX45 Transmission Cooler (Return Line On Passenger Side).jpg
2b FX35 and FX45 Transmission Fluid Dipstick 4jpg.jpg
2a FX45 Transmission Dipstick Check Chart.jpg


imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

Re: 2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby imnprsd » Wed Jan 05, 2022 10:09 pm

OP Update: The .pdf file should be available in a few days on the other Infiniti forum website. Apparently, the administrator needs to approve the post before the link appears "live" to the public.

If this link does not work I will post the .pdf in text form.

https://www.infinitifx.org/threads/2004 ... ure.37572/

Here's a little more information on the subject that may help until you are able to download the .pdf file on this other webside...

HOW TO READ YOUR FX DIPSTISK AND FILL TO THE PROPER LEVEL (DIY METHOD)

 Bring your engine up to normal operating temperatures by driving for 5-10+ minutes. Then let your engine idle for 5-10 minutes. ...At this point your tranny temp should be at 165-169F. ...Then before checking the dipstick, shift through the gears, stopping for 3 seconds at each position. …Then quickly check your dipstick and fill with ATF up to the UPPER point on the hash marks. (See graph above.) …Then add 1/2 qt more ATF and call it good!
:dblthumb:

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PalmerWMD
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Car: 2004 350Z

Re: 2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby PalmerWMD » Wed Jan 05, 2022 10:30 pm

Great Post.
Deserving of being promoted to Sticky! :yesnod

imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

Re: 2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby imnprsd » Thu Jan 06, 2022 10:12 pm

Thanks!

The Infiniti dipstick chart is very confusing, but ultimately makes sense. Here's a simpler way of measuring the correct level on your dipstick for us DIY owners who do not own a scan tool that measures transmission temperature.

NOTE: After flushing out all the old ATF as described above, my car now "rockets" and is very responsive. I highly recommend you flush your tranny fluid this way and do not let your mechanic use a flush machine or go about diluting your old transmission fluid with new transmission fluid by just emptying the pan, because the pan only holds 4 quarts and the system uses ~10.75 qts. (I do not recommend you use Lucas Transmission Fix in a properly working Infiniti/Nissan transmission.)
Attachments
Dipstick with etch mark.jpg

imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

Re: 2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby imnprsd » Sat Jan 08, 2022 12:45 pm

OP Update: The above link to locate the .pdf file was not working. Sorry about that. Please to to this Infiniti Forum website to download the .pdf for more details about this transmission flush and refill procedure:

https://www.infinitifx.org/threads/2004 ... ure.37574/

NOTES:

* The FX35 (V6) transmission cooler return line is on the DRIVER'S side. Consequently, this means the FX35 ATF flows through the transmission cooler in the opposite of the FX45 (V8).

* The FX45 has the transmission return line coming out of the PASSENGER side port.

* So depending on your Infiniti model (and other models for that matter) you should verify which line is the correct line to remove for draining the ATF out -- or you can remove both lines and drain them both in the bucket. However, you will find that only one line will expel fluid when you start the engine.

imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

DON'T OWN A SCAN TOOL THAT CAN READ ATF TEMPERATURE?

Postby imnprsd » Sun Jan 09, 2022 3:02 pm

Here's the DIY owner's approach I decided to follow when re-filling the ATF to the proper level on the Infiniti FX dipstick.

* First you need to know what the dipstick fill tube feels like "to the touch" when you reach normal operating temperature (~169F as shown on the charts above).

* To know what I'm taking about, just drive around as normal, for as long as you like, and then touch your dipstick tube.

At this point, your engine water temp will be ~182F to 185F, depending on the OAT, and your tranny fluid temperature will be ~169F. ...and the dipstick tube will be quite hot to the touch. ...And now you know what normal operating temperature feels like! However, I also need to point out, this is NOT the temperature you want to use when measuring your ATF level on the dipstick.

...But please, feel free to check you dipstick at this normal operating temperature so you know how much higher you will find it registering on the stick. Just know, that level could reach into the "first bend" on the stick and maybe higher, which is telling you this is an unreliable region to measure your ATF level. I.e., Infiniti dipsticks are read differently than any other car I have every owned. So don't assume your tranny fluid level should register within the hash marks at normal operating temperatures! (Tell your mechanic too, because they will probably make this mistake!)

* So don't be fooled! Read this post thoroughly and get familiar with the right way to fill your transmission fluid; and the right way to read your dipstick. ...One more thing, your mechanic will probably not want to take the time to use a scan tool. So you may need to convince him to do so. So, that's just one more reason to DIY if you ask me. Plus the entire process I have outlined is easy and think much better than using a traditional transmission ATF exchange pump!

* Don't want to get under your car? ...No problem. But buy a 12V, $18, transfer pump on Amazon to remove the first 4 qts of fluid out of your transmission pan; and then you only need to remove the bottom engine skid cover to reach your transmission cooler lines located next to your radiator to expel your old ATF fluid inside the torque converter, etc. (EASY PEASY!)

12V Transfer pump: Amazon.com: HYDDNice 12V 60W Oil Change Pump Extractor Oil Change Pump Transfer Pump Diesel Fluid Pump Extractor Scavenge Suction Pump for Truck Rv Boat ATV : Automotive

* FYI, I found the difference between the low-hash mark point on the dipsick vs. the high-hash mark on the dipstick is only ~3/8 qts, and this is when the fluid temperature is in the low-warm range (or about 122F).

HOW THE AVERAGE DYI OWNER CAN READ A DIPSTICK WITHOUT A SCAN TOOL

1) In the morning, when the fluid is cold... start the engine as usual. Let the engine run for 1 minute or so, as normal, and then drive the car for 1-3 city blocks, as normal, and shift through the gears.

2) Find a flat spot on the street or gas station to pull over and then do these things:

* Put put your hand on the dipstick tube (rear passenger side of the engine on my FX45) and note how warm it feels. When it feels warm to the touch, this will indicate your ATF is ~122F. (See charts above for where your ATF should register on the dipstick. ...It should be between the 2 lower notches at this point.

==> Now add 3/8 quart more of ATF and let the engine warm up more.

3) Now drive 5-7 blocks normally. Pull over and touch the dipstick tube again. This time it should feel much warmer, but not too hot to touch. ...This is the 149F point, and as you can see by the charts, your fluid level should rise and will register at the mid or higher-end region within the hash marks.

With the engine running, you will likely spend 5 minutes checking the dipstick several times, and at this point your ATF will continue to heat up, but not that much. When you feel the tube getting a hotter, but not too hot to hold on to, this is the ~149F point.

...And now you want to add ATF (1/8 qt of ATF at a time) ...but only to the top of the hash marks and no higher! ...And you are done!

Note: Your tranny dipstick is extremely sensitive. ...And each time you check the dipstick you should first shift through the gears while pausing for 3 seconds between shifts. ...Then wait 1 minute before you check the fluid level on the stick.

REMEMBER: Reading the dipstick at normal operating temperature (169F+) is not very accurate.

Tip: Use a file to etch a shinny mark on your dipstick to help you see the level and catch fluid.

imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

Re: 2004 INFINITI FX45/35 (GEN-1) TRANSMISSION ATF FLUSH PROCEEDURE

Postby imnprsd » Sun Jan 30, 2022 12:46 am

OP update: I may not have said this before, but the reason I wanted ALL THE OLD FLUID OUT of the transmission is because I tried adding my "old stand by" Lucas Transmission Fix fluid to my tranny and immediately after that I felt like the tranny started shifting smoother, but she did not "rocket" like before.

This really caused me to lose sleep and I decided to FULLY FLUSH my tranny as stated above; and I decided to use Valvoline's Max Life ATF (which plainly states it is compatible with Nissan "Matic-J and S." ...And everything turned out great.

100+ miles later and my FX45 "rockets" like before and shifts fantasic.

So I am 100% in support of never using Lucas in your Infiniti FX transmission; and 100% in support of using Valvoline Max Life ATF instead of Nissan's Matic-S fluid, because is is 1/4 the price; and when you FULLY FLUSH your tranny fluid as described above, you will really notice th power and hopefully the MPG. (...But I can't gurarantee the MPG, because these V8 are pigs!)

imnprsd
Posts: 76
Joined: Mon Nov 15, 2021 1:48 am
Car: 2004 Infiniti FX45

NO SCAN TOOL HELP - FIND THE 149F ATF POINT SO YOU CAN USE YOUR DIPSTICK

Postby imnprsd » Sun Feb 06, 2022 1:24 am

SO YOU DON'T HAVE A SCAN TOOL TO MEASURE ATF TEMPERATURE?

Solution: Here's another way to find the 149F ATF temperature point so you can use your dipstick to identify the upper hash mark ATF fill level.

1) Before the first engine start of the day... reach over the passenger side of the fender and touch the ATF fill tube with your hands... and note how it feels to the touch. This is the "feel" of the Outside Air Temperature (OAT)... what ever that is. (Use a 10mm socket to remove the bolt that locks the dipstick in place.)

2) After driving your car for the day... touch the ATF fill tube with your hands again (lightly) and now you know what it feels like when your engine is at normal operating temperature.

NOTE: It will feel pretty hot so only touch the fill tube lightly!

Now you know you know you are looking from some "feel-point" that is about -20F lower than 169F or normal operating ATF temperature.. which is the 149F point we want to find so we can use the dipstick and reach the upper level of the hash marks on the dipstick at this 149F point.

A BETTER WAY TO FIND THE 149F POINT

Swipe a digital meat thermometer out of the kitchen or buy a cheap on on Amazon for $10. Then do this:

1) After you start your car in the morning, drive it normally for about 4-5 miles.

2) Find a flat spot in the road or better still you can pull into a gas station.

3) Then stick the digital thermometer into the ATF fill tube (with the dipsick inserted) and see if you are at 155F after about 2-3 minutes. And if your not at this point... just drive your FX another couple miles more to warm up your ATF to ~155F and recheck the dipstick level.

IMPORTANT: Be sure you shift though the gears... and wait 2 minutes after that... before reading the dipstick.

WHY 155F? I am recommending your elevate the temperature of the ATF fill tube to 155F on the digital thermometer, because the ATF fill tube is metal... and there is radiant heat coming off the engine to consider. That said, the ATF fluid in the pan should be cooler than what the thermometer reads; and I estimate this will be about -5F lower than what the thermometer says.

Again, the goal is to find the 149F point, because that's how Infiniti calibrated the dipstick at the upper fill line of the hash marks.

OTHER CONSIDERATIONS

* That notch on the dipstick is the 120F level, which means the ATF fill tube should feel warm to the touch at this point... and at this temperature you should be able to grab it and old on to it for about 10 seconds without discomfort. Still, this is not a good measuring point.

* Apparently, the design of the transmission pan does not lend it self to checking the fluid level at normal operating temperature of ~169F. So, this is another reason why we need to find the 149F temperature point, because that is what your dipstick is calibrated too.

* When you add ATF you should do so at 1/8 to 1/4 qt increments or you may overfill your system. I also estimate there is only a 3/8-1/2 qt difference between the lower hash marks on the dipstick and the upper limit on the dipstick (149F).

* Remember, too much fluid causes foaming at higher, working temperatures and that's not good for your transmission ATF.
Attachments
Digital Thermometer In ATF Fill Tube.jpg
20220106_160530.jpg


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