The forbidden Transmission, at least it seems so.

[repairman54]

As a veteran of belt drive CVT's in rec. vehicles I can't imagine the amount of metal circulating in those steel belt trans. As least the belt CVT doesn't' kill the sheaves like a steel belt would.
As said sheaves would be worn badly and just getting all the shrapnel out of valve bodies and internal bearings new vs reman. a new is probably more cost effective not to mention being easier to give a decent warranty.

 

[martinq]

As a veteran of belt drive CVT's in rec. vehicles I can't imagine the amount of metal circulating in those steel belt trans. As least the belt CVT doesn't' kill the sheaves like a steel belt would.
As said sheaves would be worn badly and just getting all the shrapnel out of valve bodies and internal bearings new vs reman. a new is probably more cost effective not to mention being easier to give a decent warranty.

This is why it's so important to keep the magnets in the transmission (any transmission) clean. As the fluid and magnets load up on wear metal the magnets loose effectiveness and the rate of wear increases. The cleaner the fluid the less wear and shedding. Clean magnets are at their best. Extra magnets help.

Many of the transmissions have started off with one magnet in the pan, then were updated to two and then three. I know Fords 6R80 moved from two to three somewhere around 2016 and I've seen the same in JATCO CVTs. This is a telling clue.

 

[Exhaustgases]

As a veteran of belt drive CVT's in rec. vehicles I can't imagine the amount of metal circulating in those steel belt trans. As least the belt CVT doesn't' kill the sheaves like a steel belt would.
As said sheaves would be worn badly and just getting all the shrapnel out of valve bodies and internal bearings new vs reman. a new is probably more cost effective not to mention being easier to give a decent warranty.

I was very impressed with the 100K plus mile Jatco CVT that I rebuilt some years ago, as far as the push belt and the condition of the variator pulley surfaces, and the thing was running low on pressure, I did have to clean a small spot on one of the surfaces, even so the belt was good enough to reuse. And yes they make a lot of micro metal, and that really messes with the aluminum valves and valve body.
The cause of failure was the worn flow control valve,that is what they call it. Also the guide balls were not far from failing as well.
The pulleys, belt etc, are engineered ok in that unit, proper materials and heat treat etc. The fluid is part of the engineering as well on these, it has to allow grippage more than slippage. What is not good is aluminum valves (coated) and valve body.

With this transmission new one would not last any longer than the old one, at least there is a chance with the up dated flow control valve that is not made from aluminum. Oh and the pins rather than balls for the sliding variators.

 

[martinq]

I was very impressed with the 100K plus mile Jatco CVT that I rebuilt some years ago, as far as the push belt and the condition of the variator pulley surfaces, and the thing was running low on pressure, I did have to clean a small spot on one of the surfaces, even so the belt was good enough to reuse. And yes they make a lot of micro metal, and that really messes with the aluminum valves and valve body.
The cause of failure was the worn flow control valve,that is what they call it. Also the guide balls were not far from failing as well.
The pulleys, belt etc, are engineered ok in that unit, proper materials and heat treat etc. The fluid is part of the engineering as well on these, it has to allow grippage more than slippage. What is not good is aluminum valves (coated) and valve body.

With this transmission new one would not last any longer than the old one, at least there is a chance with the up dated flow control valve that is not made from aluminum. Oh and the pins rather than balls for the sliding variators.

Thanks for the reminder of the pin upgrade on the pulley. I'll need to get to that sometime if it hasn't already been done.

 

[supton]

This is why it's so important to keep the magnets in the transmission (any transmission) clean. As the fluid and magnets load up on wear metal the magnets loose effectiveness and the rate of wear increases. The cleaner the fluid the less wear and shedding. Clean magnets are at their best. Extra magnets help.

Too bad you have to drop the pan to clean/inspect. I've been putting this off. Just seems like a good way to create a leak when it didn't exist before (and there's no easy way to check fluid level, you know, like with a dipstick).

 

[martinq]

Too bad you have to drop the pan to clean/inspect. I've been putting this off. Just seems like a good way to create a leak when it didn't exist before (and there's no easy way to check fluid level, you know, like with a dipstick).

Our 2010 Cube (JATCO jf009e / Nissan RE0F08B) has a CVT dipstick but it has a locking clip which makes it very difficult to remove without tool(s). I've broken that clip twice on the first try (two different CVTs) but now it's easy enough to remove and check (very awkward location though).

I agree that the pan should not have to be removed to inspect / clean the magnets. There should be a removable plate or filter to allow access. I would clean the magnets at every engine oil change if they were easy to access.

I would not worry about the pan leaking, just order a gasket and be careful removing and cleaning. I have reused the OEM gasket with no issues but after 10-15 years I think it's worth installing a new one.

 

[IndyIan]

As a veteran of belt drive CVT's in rec. vehicles I can't imagine the amount of metal circulating in those steel belt trans. As least the belt CVT doesn't' kill the sheaves like a steel belt would.
As said sheaves would be worn badly and just getting all the shrapnel out of valve bodies and internal bearings new vs reman. a new is probably more cost effective not to mention being easier to give a decent warranty.

In theory, the steel belt or chain is always separated from the sheaves by a layer of oil, in boundary lubrication. But is still gripping enough to transfer some hp.
This is why I don't think generic CVT fluids are a great idea, but in practice they seem to work well enough, and better than dirty CVT fluid!