I'm getting nervous

[burrpenick]

Why? Because my 2015 Rogue is at 84k miles and the shop that 'changed' the CVT Fluid told me it is inevitable that it will fail, usually between 90-125K miles. He claims a new trans and install is around a $5-6k job when completed. This issue is also well documented in Consumer Reports and other publications.
SO, my question is this, what percentage of failures is documented before a vehicle reaches 200k miles? Does the group share my concern? I am retired and treat the vehicle w/LOVE and changed the fluid around 55K. Thanks, George in NC

[VStar650CL]

Change it every 30K and add a cooler to it. We've seen a bunch of them pass 200K trouble-free, but they all have one thing in common, religious service. They do all fail at 90~125K if the fluid is ignored, that's a fact.

[V6er]

1) did they change strainer and fine filter? if not - no wonder that all "their" transmissions die...
2) depends on your usage - if you have mostly "highwayish" miles - it is ok. if you have hot weather and major city traffics with start-stops...
3) cooler gets suggested a lot, but rarely it is suggested with company - thermostat and monitoring options... in my opinion - that is important. may be your temperatures are low anyways.

p.s. for statistics - our MY2014 has 186kmiles. partial fluid change @ dealership at 60kmiles, at 120kmiles I did partial fluid change, fine filter, strainer, transfer and rear diff; at 140-150 I did another partial fluid change and fine filter, transfer and rear diff. want to gather all my patience and do it again soon (before winter
original transmission. though car has been used mostly NE, mostly outside major cities - so... I guess that is pretty light usage.

[D1dad]

My 2018 is at 90k, I have a cooler but haven’t installed it yet and see no signs of cvt failure on the horizon. But, I have also changed the fluid at least 10 times. It’s as easy as an oil change and just as cheap when you use eneos or idemitsu fluid. This 2018 is one of the best vehicles I’ve ever owned, next to my 03 Altima that was killed by a deer at a hair under 200k. My wife’s 07 Murano was right there as well, and ran a college kid from Ohio to Louisville and back approaching 300k. The 07 had an early model cvt and still lived on.

[D1dad]

The 18 is still running on the factory alignment and I get it checked often and still drives just as nice with no rattles or noises. I must have gotten one that had QC on the line the day it came off. Uses not a drop of oil.

[burrpenick]

Does the CVT not have a factory cooler incorporated w/the radiator? D1dad says changing the fluid yourself is not that bad. I was thinking it is not something I should not tackle. Can that filter and/or screen be changed by simply removing the trans pan? No dipstick so I guess one needs to carefully measure what drains out....

[KoiMaxx]

The CVT has a fluid warmer/cooler built-in (refer to TM-28). Changing the fluid really isn't too hard to do, you can choose the cold_drain-measure-fill_equal_amount method, or the modified FSM procedure here. With the second method, would be best to have an OBD adapter that can read the temps off the CVT.

[burrpenick]

But what about the filter and or screen? I originlly thought it was not prudent- that the trans had to be out to change that, but evidently this is not so. Just drop the pan and both filters are there and easy to change? I can do the drain and fill- assume the fill has to be done w/a pump....where?

[KoiMaxx]

From what's been discussed in that thread I forwarded you, you'd only ever need to drop the pan and change that filter once for the lifetime of the transmission, and even then it might not really be necessary. The fill can be done from the top, you'd just need to remove the transmission fill cap -- note it requires a bit of finagling if you don't have a special tool to lift the latch. But I found using short flat screwdriver with a narrow handle can do the trick, then I just put the cap back offset so it doesn't latch anymore.

[VStar650CL]

The paper filter is under a cover at the bottom front of the transmission. Looks easy but one of the fasteners is actually a complete PITA. See the lower left box in this parts diagram:
https://www.nissanpartsdeal.com/parts-l ... _case.html

The screen is easily accessed if you drop the pan, and there's zero point in changing it. It's a screen, not a filter. Blow it clean or hit it with some spray solvent:
https://www.nissanpartsdeal.com/parts-l ... e_atm.html

I do recommend dropping the pan at least once after the transmission has some miles on it, because you'll get a layer of black break-in gunk from the forward/reverse and torque converter clutches. It falls out of suspension to the bottom of the pan and doesn't really hurt anything, but it's frankly yucky. Other than that, the best process for DIYers is to spill-and-fill cold, replacing exactly what you take out. You'll never go wrong that way.

[burrpenick]

Thanks on that info...I would think from your original tip that the filter s/b replaced, maybe not every 30k, but....if that one bolt on the filter cover is hard for you, would you guess a DIY could get it off and on?

[VStar650CL]

Getting up in there usually takes a short swivel socket and you need to get on it blind. It's a lot easier with the right tool. Once is fine for that filter, it's really there just to catch break-in crap. Nissan doesn't recommend ever changing it.

The CVT has a fluid warmer/cooler built-in (refer to TM-28).

For the record, the beehive is a warmer, period. Nissan calls it a cooler, but that's a flagrant misnomer. It's fed by coolant straight out of the cylinder head at around 200F, so the only time it will cool anything is if your transmission is already at a very unhealthy temperature. That's why the '10A trannies had to be retrofitted with radiating coolers, because they were blowing up from hyperactive beehives in summer heat. Nissan compensated by adding heat exchangers to the late '10A's and all the '10D's, but that's still a somewhat flawed approach. A good aftermarket cooler with a 140~160F bypass valve is the biggest favor you can do your CVT.

[D1dad]

Without a gauge to read cvt temps just start the rogue and let it idle for a few. Drain the old and measure it, a couple of gallon jugs from the dollar store works just fine. Put in what you took out. Without having a gauge you are playing roulette on the cvt temp. To hot and your fluids low, to cold and you’ve got to much, which is really bad. It’s as easy as an oil change.

[D1dad]

And I did a pan drop on the warranty trans on my 09 @75k. Total waste of time honestly. There was next to nothing. I also changed the total Pita cartridge filter on the rogue at 80k. Same thing. While the filter was darker than a new one (obviously) there wasn’t but a spec or two of in the media when I dissected it. Plus the upper bolt takes an hour to remove and install and without a lift is dam near impossible unless you’re a contortionist. Think of the cabin filter but worse. The screen in the pan is worthless from a filtering standpoint.

[V6er]

I dropped pan both times I did partial fluid replacements - both times there was "dust" on magnets.
I replaced fine filters also both times - first time it was total darkness@120kmiles, second time it wasn't that bad, but, imo, still needs replacement.

p.s. that fine filter cover - exclusive tonight:
https://prnt.sc/gm3unblxNYvN

[V6er]

The screen is easily accessed if you drop the pan, and there's zero point in changing it. It's a screen, not a filter. Blow it clean or hit it with some spray solvent:
https://www.nissanpartsdeal.com/parts-l ... e_atm.html

it's been a while since I saw it - but recently I saw pictures somewhere else and that strainer had like fleece thingie inside (it might have been something aftermarket of course).

[KoiMaxx]

For the record, the beehive is a warmer, period. Nissan calls it a cooler, but that's a flagrant misnomer.

Thanks for clarifying . I was aware that the fluid at least ran through part of he radiator, but I guess it only helped marginally. It seldom gets particularly hot in my neck of the woods, and I've only ever gotten the fluid hit 90C (~194F) on mine maybe once in the seven years I've had it.

[VStar650CL]

Yah, instead of exerting positive control over the heat flow, they're pumping heat in with the beehive and then counteracting it with the heat exchanger. That works fine most of the time, but a long pull up a mountain on a hot day will overwhelm it because the radiator tank temperature will rise with the engine load to where it can't cool. That's why adding a radiating cooler in series with the exchanger is the hot -- er, cool -- ticket.

[KoiMaxx]

Speaking of temps, what is the number that one should actually get worried about deterioration?

[V6er]

Yah, instead of exerting positive control over the heat flow, they're pumping heat in with the beehive and then counteracting it with the heat exchanger. That works fine most of the time, but a long pull up a mountain on a hot day will overwhelm it because the radiator tank temperature will rise with the engine load to where it can't cool. That's why adding a radiating cooler in series with the exchanger is the hot -- er, cool -- ticket.

so - your suggestion would be route cvt fluid coolant to its own radiator (avoiding heat exchanger and oem radiator)?

[V6er]

Speaking of temps, what is the number that one should actually get worried about deterioration?

I would go with 100+Celsius (long term).
short term (like VStar suggest hill or something) up to 110.
(now it would be interesting to hear VStars opinion

[VStar650CL]

so - your suggestion would be route cvt fluid coolant to its own radiator (avoiding heat exchanger and oem radiator)?

No, put the cooler in series with the exchanger. The exchanger aids in warming the transmission up quickly, which is important too. Cold parts wear a lot quicker than warm ones. You just want to keep it at warm, not hot.

[VStar650CL]

Speaking of temps, what is the number that one should actually get worried about deterioration?

I would go with 100+Celsius (long term).
short term (like VStar suggest hill or something) up to 110.
(now it would be interesting to hear VStars opinion

Deterioration numbers from the TCM are worthless, they only account heat and not shear breakdown. Ideal temps are between 165~175F, and anything 200F or above is definitely taking a toll on the fluid.

[phmichel]

Speaking of temps, what is the number that one should actually get worried about deterioration?

I would go with 100+Celsius (long term).
short term (like VStar suggest hill or something) up to 110.
(now it would be interesting to hear VStars opinion

I installed Hayden by-pass coolers on both our 2013 Rogue (cooler installed at 80k, now at 170k miles) and 2017 Quest (cooler installed at 90k, now at 130k miles). They are literally life savers for the CVT's.

As far as temps go the way I read the manuals and the heat points in CVTz50 is:
68°F (20C) - min (considered "cold").
122°F (50C) - min operating temp.
163°F (73C) - ideal operating temp.
194°F (90C) - max operating temp. This is the redline for the CVTz50 app. Deterioration starts to accumulate as the CVT spends time above 194F. The higher the temps, the greater the increase in the deterioration calculation. I don't know where the Nissan and Jatco Engineers came up with the deterioration formula but I agree with VStar that it's pretty much useless.

I've never had our Rogue go into limp mode but before I installed the cooler it could hit 210F+ climbing our Oregon mountains in the summer. Now it never exceeds 170F even when climbing 10-15 miles of a 7-10% grade in a 90F+ ambient temp. It cruises at 165F and below on the flats no matter how hot it is outside.

Our Quest is the same story, although it did go into limp mode in heavy summer traffic once right before I installed the cooler. It hit 224F (107C). Did two D&F's back to back right after that.

These are just my observations. I can tell you that the coolers in our vehicles make a huge difference and I hope to get at least 250k+ out of these cars now that the CVT heat issue is resolved.

VStar: What are your thoughts?

[VStar650CL]

VStar: What are your thoughts?

You're on the right track. I recommend coolers to everybody who will listen.

[phmichel]

VStar: What are your thoughts?

You're on the right track. I recommend coolers to everybody who will listen.

[V6er]

so - your suggestion would be route cvt fluid coolant to its own radiator (avoiding heat exchanger and oem radiator)?

No, put the cooler in series with the exchanger. The exchanger aids in warming the transmission up quickly, which is important too. Cold parts wear a lot quicker than warm ones. You just want to keep it at warm, not hot.

btw - any experience with exchanger cleanliness? does it collect dirt inside it...?

[VStar650CL]

The exchangers are generally a problem only if the transmission is making metal chips. The passages are incredibly tiny (under a millimeter) and they do clog easily if there's anything to clog them. There generally isn't in a healthy transmission. Full belt CVT's have only two clutches (F/R and Torque Converter) and neither makes much debris, the F/R clutch works only when changing directions and the TC Lockup works only when the car is cruising and thus sees very little engagement torque. So you never see "ATF soup" like you see in an old A/T, and there's really nothing to clog the exchanger. We only worry much about them when replacing a transmission, because often the failed unit was making chocolate chips before it died. Always back flush them, forward flushing does no good. Here's why, check out the miniscule size of the cross tubes:

Heat Exchanger Tubes.jpg (64.16 KiB) Viewed 2137 times

[burrpenick]

what cooler do you like? I see 4 and 6 row conventional type. And is the Valvalene fluid OK?
https://tinyurl.com/2fzdufks
or
https://tinyurl.com/4ue6jfb6

[VStar650CL]

I have a Hayden 697 in the wife's car and I'm frankly impressed with it. It has a patented reed valve setup which makes it non-directional, and the embedded H-valve cracks at 160F, a very usable temperature for CVT's.

Valvoline fluid is okay but it's noisy just like NS3. I get NS3 at a huge discount (sometimes free leftovers) because I work at a dealership, but based on my customers' experiences, if I had to buy it at market prices, I'd get Eneos. That's based on living in Arkansas, if I lived in Wisconsin or Canada I'd opt for AMSoil because of its superior cold performance.