In the last week I have responded to two posts here, relaying a message regarding "maintenance free" automatic transmissions. Like so many different makes and models produced over the last fifteen years or so, "maintenance free" automatic transmissions have become the norm. Although they have been designed with higher reliability, to last longer without ever having to change the ATF within the warranty period, these sealed system transmissions will self destruct not long after the powertrain warranty has expired. The ATF used in these transmissions is not all that special. Although there will be a specific fluid grade to use, there is nothing but degradation that happens to the ATF from the day the vehicle is first driven. After 50K miles, the original ATF is unrecognizable as an adequate lubricant and hydraulic fluid. After 100K miles, the ATF is almost worthless for its intended purpose and the transmission it's used in has begun to experience premature wear. If it makes it to 150K miles without catastrophic failure, some irreparable damage and noticeable slippage will be evident. There is no expectation the transmission will last 200K miles unless you ignore the absurdity of the manufacturer's claim that the transmission is supposedly "maintenance free" and change the ATF at least every 50K miles from the beginning. There is no real benefit of being "maintenance free" except to dealerships' new car sales and automotive repair shop's services. Nothing's free. If you have a Armada, QX56, QX80, or any other make and model vehicle with a "maintenance free" transmission and have never had the ATF changed because you thought it was not necessary, ever, think again.

Agreed.
New fluid every 50,000 miles for me.

Well said!

The problem with the QX56 (and other Infiniti/Nissan models) is that even if you proactively replace your ATF on a more normal frequency (for me, at least every 50K miles or sooner), the transmissions still fail prematurely. My 04' QX56 has 140,800 miles on it and I'm on my 3rd transmission. My original failed at 70K miles (I had replaced the ATF and F/R diffs and transfer case fluids at 45K miles or so). Sourced a rebuilt unit from Santa Monica Infiniti at that time. That one lasted until about 135K miles, at which point that one failed. I had that unit rebuilt by a local and reputable transmission shop and so far so good now. The shop that did this latest work recommends annual ATF changes and they are covering the first 3 under what I paid them for the rebuild. Nissan transmissions are not designed for long-term reliability ...to anyone who has a product from this company, if you haven't had tranny issues yet, your day is coming. And FWIW, I do not haul anything routinely with this truck. On occasion, I will rent a trailer to haul some mulch or plants, or trailer my motorcycle to the shop when I have to but otherwise, I do not haul anything with this vehicle.

I've said it before, CVT's are the only trannies that can live forever. Conventional A/T's all have a maximum possible lifetime limited by the sacrificial band and clutch material. No matter how frequently you change the fluid or how much you "baby" the drivetrain, you can only postpone failure, not prevent it. Death, taxes, and A/T rebuilds are all inevitable.

VStar650CL wrote: ↑

Mon Jan 11, 2021 12:28 pm

I've said it before, CVT's are the only trannies that can live forever. Conventional A/T's all have a maximum possible lifetime limited by the sacrificial band and clutch material. No matter how frequently you change the fluid or how much you "baby" the drivetrain, you can only postpone failure, not prevent it. Death, taxes, and A/T rebuilds are all inevitable.

Sorry, what is meant by a CVT? I'm not familiar with that. All I know is people who have Toyotas and Hondas and many other brands are getting hundreds of thousands of miles out of the original tranny. To have one go out every 60-70K miles is absolutely unacceptable.

CVT is "Continuously Variable Transmission", they have a metal belt and a pair of pulleys that let them work at any arbitrary transfer ratio. Because they have no "sacrificial" material to wear out, their lifespan is potentially infinite if they're given frequent fluid changes.

Socaldiablo wrote: ↑

Wed Jan 13, 2021 3:16 pm

Sorry, what is meant by a CVT? I'm not familiar with that. All I know is people who have Toyotas and Hondas and many other brands are getting hundreds of thousands of miles out of the original tranny. To have one go out every 60-70K miles is absolutely unacceptable.

Nissan CVT (Continuously Variable Transmission)


How A CVT Works by TEAM Industries

Nice vids, very explanatory!