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when did the CVT fail?

  • less than 1,000 miles

    Votes: 2 0.5%
  • 1,000 to 5,000 miles

    Votes: 7 1.7%
  • 5,000 to 10,000 miles

    Votes: 11 2.7%
  • 10,000 to 20,000 miles

    Votes: 18 4.5%
  • 20,000 to 40,000 miles

    Votes: 28 7.0%
  • 40,000 to 60,000 miles

    Votes: 30 7.5%
  • 60,000 to 80,000 miles

    Votes: 35 8.7%
  • 80,000 to 100,000 miles

    Votes: 30 7.5%
  • 100,000 to 120,000 miles

    Votes: 200 49.9%
  • 120,000 to 150,000 miles

    Votes: 12 3.0%
  • 150,000 to 200,000 miles

    Votes: 13 3.2%
  • above 200,000 miles

    Votes: 15 3.7%
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Wow ! I spent some time off and on reading this whole thread. Some interesting story's here, and some misinformation from some non CVT experts. Since I know the insides of the older 2004 version of these transmissions fairly well now, and have posted many threads or posts on the topic I'll try to explain some of the failure modes that I see and have studied like a PHD would study for an exam.

I have done a rebuild/ overhaul of the Jatco REOFO9A / JFO10E also known as CVT3. The particular one I worked on did the usual slip deal according to my daughter, she took it in to a shop they got a few DTC's P0868 was the main one that I recall. Before even attempting the job I did alot of study work.

Here are the main failures these type of transmission can have not in order, 1. Worn flow control valve 2. Broken variator sliding key balls (my nomenclature) 3. Broken push belt 4. Leaking valves in valve body and other valving issues. 5. Problems with electrical control devices (stepper motor, solenoids, electrical connections etc.) 6. Worn or metal deposits on the variator pulleys. 7. Issues with the torque converter 8. Main mechanical failures.

All of the valves are a coated aluminum and the valve body is also aluminum no coating of course. My finding is the coating on the valve will wear out before the valve body bore, since the pump housing is the same type of aluminum as the valve body, that is what the flow control valve fits in. It is the flow control valve that gets worn badly and can leak or stick, and not so much the bore in the valve body.

Transgo makes an easy drop in no machine work needed flow control upgrade that works good in this transmission version, it is not aluminum. This valve can not be accessed without removing the transmission and the bellhousing part of the case to remove the pump housing that contains the valve. As far as the forward and reverse clutches go, they are similar to a normal step transmission and receive very little wear since they are just an on and off deal, they are not used for changes of gear ratio or part the the gear shifting process.

I would say that when the control pressure drops those clutches would be the least likely to slip, and any noticeable slippage will be the belt pulley interface. If the slippage continues too long and too many times the heat generated helps to deposit some of the belt material to the hardened face of the pulley, and yes it can be hand polished off, most shops that do rebuild these and have a lathe will do that in a lathe. Something special about the CVT belt and pulley system, there is tremendous pressure squeezing the tapered pulley faces against the metal belt, all the time the system is either variating or the action of the belt entering or exiting the pulleys is a friction point, since it is the goal of the system to grip and not slip. Problem is there is always slippage happening, this is why the manufactures special fluid is needed. It has to fight the slippage friction while at the same time helping the system to grip and not slip, two conflicting demands on the fluid.

These transmissions make a lot of micro steel particles, that can wear the aluminum valves, as well as seal rings, gears, roller element bearings etc. and is reason to change the fluid, unlike what some have said in this thread.

Some of the design of these transmissions is okay, I was impressed with the hardness of pulley faces, and lack of pulley and belt wear at around 130,000 miles, I do not know if there was any fluid changes done or not.

This transmission did have very little metal deposits on the pulleys. I did see many things that needed improvement, those improvements would add material and weight but would be very helpful during assembly, and could be a reason that some remanufactured transmissions don't last.

One of the main and simple improvements that certain rebuilders of these transmissions came up with is the use of dowel pins instead of the small steel balls for the variator sliding keys, those small balls are the main engine torque transmitting devices to and from the variator pulleys. A ball has very little surface area contact and does indent the grooves that they run in, if those dents are deep enough then the balls can catch in them like a tire in a hole, then the moving action can break down the hard surface of the ball causing it to chip away and fail some point in time. If the balls break and fail the transmission would have a weak slipping movement for awhile with limited variation from the abrasive grit of the balls in the space, or the outer sliding member would crack then no movement would happen, similar to a belt failure. Those dowels cure that problem, and Jatco should have done that in the first place. They may now exist on newer versions.

Where Nissan and the transmission manufacture messed up the most, is not letting out the proper overhaul manuals and parts for outfits and interested people to dig into these to figure out the problems, and then listen to or pay those entity's for the improvements. Maybe its a pride thing for them or? This goes for all automotive manufactures, there are a lot of good ideas they are missing out on to help improve their products. I guess its cheaper to do recalls and tons of warranty work. What it has done the most is turn people away from their product.

Getting some parts for these transmissions is impossible, some times its a make some other part fit type of deal. Yes shame on Nissan. How come you can order a rebuilt transmission from the dealer yet can't get some important parts? The parts the rebuilder will have to do the job.

I think the main cause of seal problems with the transfercase is installing the assembled stub shaft and CV shaft together, it is so easy to mess up with all that weight and would be close to impossible to guide that stub axle in on the right hand side and not possibly damage all the seals it has to go through, it has to be perfectly straight going in, every thing to do with that stub axle install and bearing is very critical, I bet not many Nissan techs can do it correctly.
 

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My Murano had been driving and acting fine until ~ 200 miles ago. At that time I noticed a turbo-like whine when the car was in gear and starting from a stop. It seemed to disappear at ~ 10-15 MPH although this may have been because of road noise.

I decided to take it in to the dealer. The noise was obvious to them when the car was in gear and not even moving.

Long story short.....a new transmission is being shipped in for replacement. May be the torque convertor I'm told, however, the whole tranny is being replaced.



Update:

Took about a week to get the transmission to the dealer and in the MO.

The service ticket showed a final tally of parts and labor of $5717.17:eek:

The good news is the new CVT seems to be working well, and quietly as before. And I didn't have to pay for any of it!!:D
Wow I think I need a new tranny as well, how many miles did yours have? Mine is 2013 with 166k started to fail a while ago.
And how did you not have to pay that?
 
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