Transmission fluid flush..... yes or no?

N

neva4self

Member
Car
2009 FX50
I just hit 35,000 miles on my FX and I was considering flushing my transmission fluid. Everyone I speak with tells me that if I am going to do it, that I should do it asap meaning, better to do it while the mileage is lower as apposed to later on. What is a good mileage to do it at? The FX50 is still somewhat choppy driving, IMO Infinti hasn't worked out all the issues with the FX50's TCM/ECM updates. It's hard to tell whether or not I feel like it needs to be done because any shift issues I feel like I experience while I'm driving I automatically chalk it up to the TCM/ECM issues, it's not like I have a lot of shift issues.

Just wanted to get some feedback on whether or not I should do it at least once. I hear it's a costly process at the dealer so I don't want to do it unnecessarily.
 
Considering the same at my 30,000 mile service on my 11 FX35.
 
35k sounds a bit early in my mind. I did a drain and fill at 60k on my first gen. Opinions on this service varies greatly though.
 
There's no official time to do it since technically you run "lifetime" fluid. So either do it now, or don't do it at all and roll the dice. Just like any other car, experiences vary. Some people do it at 30K and the fluid is burnt and black, others do it at 100K and the fluid still looks brand new.
 
Not sure on the 50's, but the 1st gens are recommended to get a drain-and-fill; not a flush. The pressurized flush is what can break away particles on the aged seals and later attribute to leaks. And this is also why flushes are not recommended if not done in a while.
I would not flush. I like clean fresh fluids. I would drain and fill.
 
I did a flush at 30K miles and it was a waste of money. I paid like $350 dollars with tax. It takes 16 quarts of matic S fluid.

Really on the 2nd gen its not really necessary because our 7 speed transmissions are sealed units and is said to last the lifetime of the car even though we all know any fluid breaks down after a while.

Where its a drain or fill or a flush, the dealer still needs to use the machine to pump the fluid back into the transmission because its sealed and there is no dipstick on our 2nd gens.

The longest I would go on the fluid is 100K miles. In the end its up to you. Flushing the fluid now this early at 35K miles won't hurt anything. But honestly when I had it done I saw no benefit nor did the car drive any differently than before the flush. The only difference was that my wallet was $350 less than it had before lol. Also it helps keep a piece of mind considering if these transmissions crap out they can cost upwards of $8k to replace out of warranty.


Also remember if the dealer says a flush is like $180-$250 they are trying to use aftermarket BG fluid which is NOT recommended for use in our cars. A full Matic s fluid flush will always be $300+
 
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Ok so now I'm even more conflicted about whether I should do it or not. Looking at my odometer today I realized I'm almost at 36,500 not 35,000. I think the dealer suggested this service at 50k or 60k I can't remember. I'm still up in the air about it though I just don't want to waste money unnecessarily. Like Aaron said there is nothing cheap about this service on a 2nd Gen and there is no option to do this myself. I think I'm going to do it just for the peace of mind on having fresh fluid from this mileage point onward. Hopefully I have a good experience with it. Thanks for the feedback fellas.

---------- Post added at 07:53 PM ---------- Previous post was at 07:52 PM ----------
jdTrader said:
wait for 100k. Follow the manual and don't over do it is my advice. Aaron nailed the answer.
Click to expand...

I didn't even check the manual JD. Is 100k what the manual recommends? If so, I'm definitely going to wait, no brainier.
 
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No the manual doesn't state 100k miles but that is usually what anyone recommends for lifetime fluid swap in a sealed transmission. Although at 100K miles I would never do a flush, only a drain a fill.

The dealer is going to suggest for you to do it now not because they care about your FX's transmission, but because they are going to take a big chunk of change from your wallet.

The factory service manual lists it under periodic maintenance but the do not specify a certain interval or mileage. It only specifies to replace it if your servicing the transmission like doing a repair or something of that nature.
 
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Manual says nothing about it. It excepts the lifetime transmission fluid from the service intervals. 100K is just what the general consensus is. So officially, the answer is you never have to. But in reality, you probably would want to do it at some point.
 
And like I said its all up to you. If it will make you sleep better knowing you have fresh fluid go for it.

If I hadn't done the flush at 30K miles like I did before I probably would of had it done around 60K miles.
 
From manual:
Transmission Fluid – Automatic orManual, Differential Oil, Transfer Case OilVisually inspect for signs of leakage atspecifiedintervals. Iftowingatrailer,usinga camper or car–top carrier, or driving onrough or muddy roads, replace the trans-mission fluid/oil at every 30,000 miles or24 months (except models with 7-speedautomatic transmission and the M35/EX35with 5-speed automatic transmission).





and every place it says to replace automatic trans oil it has a * next to it and it says:

  1. Except models with 7-speed automatic transmission and theM35/EX35 with 5-speed automatic transmission.





There is no reference that I can find of ever changing the 7 speed trans our cars have. So the dealer is correct in stating that it is lifetime.

If the japenese are telling us don't mess with it. Why mess with it? It's like a parent that knows better that says don't touch and the kid touches the pan and hurts himself.
 
But if you pull up the factory service manual though not the regular manual that comes with the car, it is listed under periodic maintenance without a specified interval.
 
I don't know where I got that 100k...possibly from someone else.

By the way, my dealer HIGHLY URGED me not to touch the transmission oil at 60k when I came in for a 60k service. For some reason in my head I was wanting to do something better but sometimes less is more.

---------- Post added at 08:21 PM ---------- Previous post was at 08:20 PM ----------
Fire0nic3FX said:
But if you pull up the factory service manual though not the regular manual that comes with the car, it is listed under periodic maintenance without a specified interval.
Click to expand...

he's not getting his trans serviced.
 
I heard the 100K thing on BMW and other forums where they have sealed units too.

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It is still okay to change it though Its not going to hurt.

Same goes for power steering fluid or brake fluid. The service manuals never state to change it but you still can its not going to hurt anything. A waste of money yes but nothing that will do harm.
 
And by the way....cleaner is also not necessary better. I have a friend that works as an engineer on transmissions here at the GM plant in Michigan. They have machines that put transmissions through 1,000,000 miles in no time. I would assume Nissan does as well. Who knows maybe when the trans gets older with the oil, the oil getting dirtier over time is actually what those engineers want to work best with a transmission that has parts that get wear in time as well. You could actually be doing much worse by putting clean trans oil (drain and fill - I'm not even talking about flush) because the engineers designed the parts of the trans to work at 100k, 200k, etc with aging trans oils not you changing them going against what the manual says for you to not touch the trans oil.

I had one friend with a malibu that changed his trans fluid at the dealership 20k ahead of schedule. 2k miles later his trans completely broke down literally every part inside grinded against each other and he needed a whole trans. Car was done. He was thinking he was doing something good "piece of mind" so to speak and see what happened. Nobody knows if that was the cause but listen if the engineers are telling us one things why are we fucking with them. They know better than use.
 
Guess I'll make a decision at about 60k then. From all the feedback it seems like most agree 30k is too soon, 50k-60k sounds more reasonable if it's going to be done at all, and maybe don't do it all if the situation doesn't call for it. I guess at 60k I will revisit my feeling on whether or not to do it and if I decide not to do it then I probably won't still have the car by the time it needs to be done. I will probably have moved on to a newer model FX :good:.
 
We have had a few FX guys mention the last few months about significant trans problems....I wonder if they had their 7speed trans fluids changed going against what the Nissan engineers tell us to do. One dealership says DO NOT DO IT and another says DO IT because they don't give a rats ass. So now I'm starting to wonder if over time the trans that had trans oil changes will actually have a higher risk of having trans issues since the cleaner new oil was not engineered to work with a trans with more worn parts....and using this logic, the later you change the trans oil, the worse of an impact you have especially if these trans were designed to run 1 million miles with the same oil.

Next time we see a trans failure I'll make sure to ask the member if they ever had their trans oil changed (if they have the 7speed) and if they didn't (did they buy it used because the previous people could have). It will be interesting to see the results over time.
 
Jonas I was just thinking like you with the fluid thing that it might harm it in the long run but I spent an hour arguing with the service manager about thia and found out of they flush fluid out on many transmissions a month for years already without no complaints. They told me as long as I service it there they got me covered for my transmission with a guarantee although I may not even keep it long enough to find out. I have since put 23K miles on this fluid without issues. She still drives the same. Im at 53K miles Noe and had it done at 30K.

I don't know about GM Jonas bu the REAL reason thy sealed the transmissions on our is not because they want the fluid to get dirty but was to prevent outside shops from putting the wrong fluid in it and screwing up the transmmision. I was told by people at Infiniti that they constantly get warranty claims on transmission fluid that was tampered with by outside shops. If they make the difficult to service the outside shops wont touch the fluid.


Jonas look up under the hood you see labels that say uses matic s only or look the the FSM they always boldy highlight to use matic s only. Manufacturers are tired of outside shops messing with the Transmissions.

---------- Post added at 08:50 PM ---------- Previous post was at 08:46 PM ----------

Jonas I had severe transmission isssue way before my fluid change. On our rides its always been a software issue. That's why after the recent software update I have no issues. All these transmission problems everyone has is not fluid related but software related because all these 7 speed issues are the same exact problems not just on the FX but almost every Infiniti owner that has the 7 Speed ex: ex, M, qx, G

---------- Post added at 08:56 PM ---------- Previous post was at 08:50 PM ----------

I know this argument is all in good fun though :P. They argue about this sam exact topic on the G forums.

The real answer it always leads to is that there is no right or wrong to this. Some say service others say don't touch it. In the end its your decision and your money.

The only real way to find out if its okay is to send the oil in for an oil analysis report. They also check trans fluid.
 
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