7AT maintenance question
 

I did a search but wanted an answer from someone that might have already been through this issue....

I've always heard two sides on this issue with the 7AT.
if it ain't broke don't worry about it. i am talking about servicing the transmission. i'm at 37,000 and just looking for some advice. it shifts perfect
no problems and it's a DD. Thanks for any comments.

I'm a believer in if it ain't broke, don't fix it....just my 2 cents.

I believe in manufacturer recommendations and the service manual is plain: no service or fluid change. My dealer won't service because of this.

I would refer to your Service and Maintenance guide for clarification but the schedule listed is to replace the fluid at 30K.

http://www.nissanusa.com/content/dam...2010_N_SMG.pdf

I would have your trusted mechanic inspect the fluid just to be safe but I have been told to go until 40K normally

Yikes, change it. All they do is overheat and blow up.

wilsonp says manual says no service needed.
others say 40,000 I'm confused?

I'd leave it as is, as per page 10 of the maintenance manual.

If you look more carefully at the SMG, the 30k change does not apply:

5 Automatic transmission fluid except for 370Z.

Thanks for the clarification guys.

There you go OP, and I have learned something as well :tup:

So when do you service the 7AT ? And which tranny fluid do you guys recommend?
Red Line as good for Tranny's as it is for engine?

huh i thought these 7AT trannies were pretty strong. Do you have any links for more info on the 7AT blowing up and overheating? Damn really don't want to spend 400 on a GTM tranny cooler. Could someone recommend a different solution? I'm guessing I have to piece together my own kit.

No other option. You either spend 600 to make it run correctly or 7k for a new one. I haven't seen a stock tranny went out yet only forced induction

7AT are sealed units because no basic servicing is needed.

Now if you wanted it serviced anyway? You would have to bring it in to the dealer.

There's specific procedure and special equipment thats used when draining and refilling of transmission

Thats why nissan made it non serviceable for the basic mechanic.

I hope that made sense.

I change my fluid every 20,000 km, its a pain to get it filled .

Can you give any details about special tools need, procedures & what not?

Thanks :tiphat:

USE OEM ONLY!!!!!

The nissan tranny's are supersensative to aftermarket oils. These tranny's are specially engineered and any discrepency in the formula may cause adverse reaction to the tranny operation. As stated before the transmissions have a sealed design to keep most non-certified mechanics out. Our tranny oil can run 200k miles but nissan will change it for posterity and insurance, between 100k-120k miles. Higher performance tranny oil upgrades should be discussed with the GT-R specialist at your dealership. I think nissan does make the higher grade oil at a premium. But if you aren't running turbo's? You really don't need it.

PS Redline is recommended on MANUAL TRANS ONLY or as Engine oil for either car

^ wow thats pretty crazy it can last that long.

let the dealer change your fluid.

Thanks for advice.

Repped for an informative post! :tup:

approx how much does a tranny flush cost at the dealer?

Old and probably bought the thread back but.... my transmission blew and i think its because i overheated it... plus it was overfilled... so yes a stock tranny can overheat and blow also because of overfilling! I did not overfill it i meerly watched as he overfilled it because he thought it was ok...

While I understand the tranny is a sealed unit common sense still applies. Transmission fluid is a lubricant and like all lubricants wear out over time. I had mine replaced at 45000 miles at my local Nissan dealer and have never regretted doing so.

Did my own at 71k when I bought the car 2nd hand. Shifted much better afterward.

I change mine at 20k mile intervals. Just did my first change a few months back with 20k on the odometer. The fluid was dark and the 2 magnets were full of metal. It may be true that it has a lifetime fill... If you want it to have a finite life of about 100k miles before shifting issues arise. I drive 25k+ per year so I want it to last.


Alldatadiy.com has the procedure and I have found it online as well. I took the pan off to clean the magnets and pan of debris. While it was off I drilled the pan and Mig welded 2 bungs into the pan. One I have a temperature sensor threaded in to that goes to a tranny fluid temp gauge - part of the fill procedure is having the transmission at 104 degrees fluid temperature. The other I use to fill the pan. The catch is during the final fill when setting the fluid level, the car must be idling in park as you pump fluid in and then let it drain out of the overfill plug. There's a standpipe in the pan and when the fluid is at 104 degrees it is at the correct level when idling in park and no more fluid drains out. The first time I did it I drained the overfill plug at temperature with engine off and I was low on fluid and had some shifting issues until I corrected the level.

So drilling the pan and adding bungs isn't necessary but it's what I wanted for keeping and servicing my car long term. The overfill plug hole is pretty small and you would need to fabricate a special adapter(it is impossible to get one anywhere. I tried, even from overseas) or stick a small hose up past the standpipe to pump fluid in. And the car must be perfectly level while you perform service. As far as reading the temperature I used a trans temp gauge in one of the bungs as well as a harbor freight temperature gun with laser and the two were within a few degrees of each other when taking temp on the bottom of the pan. Also be sure to only use Nissan matic S fluid for servicing.

I am a firm believer in changing automatic transmission fluid. It gets dirty with use. All an automatic transmission is is a bunch of wet clutches and valves. Valves get sticky from metal and clutch debris in the oil and then you have shifting issues. And the Z appears to get very dirty very fast. One other note is that it doesn't have a filter typical of most American cars. It uses a steel mesh screen bolted to the valve body with quite a few bolts

So without plagiarizing the maintenance manual here is a basic rundown of how to service

Engine off, Drain fluid from pan using rearmost plug on the pan and then replace the plug.

Remove the plug towards the front of the pan and pump fluid into the pan keeping in mind there is a standpipe that is about an inch tall.

Once fluid overflows from the pan or after adding about 3 1/8 quart, reinstall the overfill plug. Run the engine until trans reaches 104 degrees fluid temperature. Also shift into drive and reverse with foot on brake to circulate fluid.

Here you can either drain and service again to flush the fluid or do the final servicing.

For final service ensure you have filled 3 1/8 quart of fluid or until fluid spills from overfill port. With engine RUNNING and fluid temp at 104 degrees remove the overfill plug. When fluid stops dripping it is at the correct level in park. Basically just like servicing any automatic in park, engine running , the difference being you are draining off excess fluid while running instead of using a dipstick.

Also be sure to only use Nissan Matic S fluid. Nothing else

Make sure whatever method you choose to fill the transmission through the overfill port actually works before draining your fluid. Otherwise you will be stuck lol. I have not tried a small piece of hose. My other idea was to purchase a spare overfill plug from Nissan or a bolt with correct thread and crush washer and drill out the middle and then weld some type of fitting to it that you could hook a hose on to. This procedure is probably not a great place to start for the novice mechanic but for a decent mechanic with some ingenuity it can be done fairly easily

A small 1/4 in clear nylon hose fits perfect and is stiff enough that it can be shoved in and hold a tight seal.

V8,

I didn't pull the pan when doing mine. How do you reseal? Is there a gasket? If so do you have a part number? Is there a filter once the pan is off that can be replaced? If so do you have a part number?

Thanks :tiphat:

Check with "Whatever it takes transmission parts" . They have a website and are great to work with with good quality and low prices. You can look up the transmission and gasket on their site or call. The gasket that came to the local store was great quality. Nice thick and robust unlike the factory paper style gasket. I think it was like $6
As for filter you would have to check with them. The z doesn't have a filter like American cars. Just a steel mesh screen bolted to the valve body with a number of bolts. I didn't change mine but it looked fine. I think it's definitely worth cleaning out the pan there was a lot of sludge and debris.