- Joined
- Jun 26, 2017
- Messages
- 35
Hi all,
I'm running a 2011 Subaru Outback, 2.5i with CVT. The car's great, and I've been running RomRaider to pull the ATF temperature for the last week or two.
That being said, I'm finding that in my commute, about 10 miles each way to/from work which is 5 highway (65 mph) and 5 city (stop and go, posted speed limit 35 mph) - my CVTF is heating up from whatever the ambient is to around 110-120 F by the time I get home. I work shift work, so I have the benefit of driving to work at 4:30-5:00 AM when nobody's on the road but me, but I also have the "drive home" portion with moderate traffic. It takes about 25-30 minutes to get home on that 10 mile trip.
I know that temperatures above 210-220 F will start to leave varnish and lead to failure when done regularly.
So, I was surprised that the fluid never reaches a normalized level where the cooling mechanisms find a symbiosis with the temperature.
Now, here's where I'm confused. Normally, I'd say, "That's great! Heat is the number one killer of transmission fluid." And now, the curveball.
Subaru advertises their CVTF as lifetime fluid, unless you're towing. Obviously, towing must put a tremendous amount of stress on the fluid's lubricating and cooling properties.
However, Subaru Canada says that the CVTF must be changed about every 100,000 kilometers - or just over 60,000 miles. That falls in line with the major maintenance including spark plugs and other things for the boxer engines in their fleet.
I reached out to Subaru Canada about the interval. They say that because of the cold, the CVTF falls into a severe change schedule therefore requires a drain and fill every 100,000 kilometers. However, my Subaru USA booklet says it's only "severe" if you're towing for the purposes of CVTF.
So, that's where I'm confused. I would think that me being in a slightly more southern climate (NJ) is warmer (temperatures can exceed 100 F in the summer, and most of the time are 90 F or higher for June-July-August), and also get pretty cold in the winter (below freezing is expected for January-February)...
I don't tow, so that's good, but it got me thinking about the cold thermal properties of the CVTF. I've never had any type of irregular functioning of my CVT, but I'm still curious nonetheless.
My 2011 uses a "C-30" CVT from the factory fill. It takes about 12 quarts of fluid, but much of it is kept in the valve body and torque converter; as a result, if you do a drain-and-fill you're looking at somewhere around 6-7 quarts actually replaced. So, if you did a D&F at 60k miles, you've really got 50% of the fluid with 0 miles and 50% of the fluid with 60k miles still. Likewise if you did it again at 120k: 33% with 0, 33% with 60k, and 33% with 120k miles.
Modern Subaru CVT's now use CVTF-II fluid, which is green in color. It is backwards-compatible with the C-30 (blue in color). They also use a High-Torque CVT Fluid variant for their 3.6R (6-cylinder Boxer engine) and their XT (4-cylinder Turbo coupled with the FA DIT series engines). The high torque fluid is not compatible with the C-30 nor CVTF-II. There are several instances of people on the Subaru forums citing transmission failure and problems when using blends of the fluid when having the D&F done at non-Subaru shops. Doh!
I suppose the additive packages included with the proprietary CVTF are replenished which is usually a good thing, but at some point, it becomes a bad thing to replace old fluid because the fresh fluid can act like a solvent and disrupt some of the gunk otherwise encapsulated in the CVT and lead to valve body or solenoid failures, right?
I'm in the stages of buying a Subaru 3.6R next winter/spring, so I wanted to have a plan in place going forward for maintenance. I want this next car to last me a very long time. To me, these things aren't as disposable as people make them out to be. It's more than just an appliance or a thing, it becomes an extension of my very being, which is why I take great pride in doing my own maintenance and doing it properly. Not to digress from the purpose of this thread, I plan on running an OEM Subaru oil filter with Pennzoil Ultra Platinum 5w30 in it exclusively from the start.
So, does my CVTF never getting nearly up to "ideal" or "symbiotic" temperature cause problems?
Thanks, all. I appreciate your feedback.
I'm running a 2011 Subaru Outback, 2.5i with CVT. The car's great, and I've been running RomRaider to pull the ATF temperature for the last week or two.
That being said, I'm finding that in my commute, about 10 miles each way to/from work which is 5 highway (65 mph) and 5 city (stop and go, posted speed limit 35 mph) - my CVTF is heating up from whatever the ambient is to around 110-120 F by the time I get home. I work shift work, so I have the benefit of driving to work at 4:30-5:00 AM when nobody's on the road but me, but I also have the "drive home" portion with moderate traffic. It takes about 25-30 minutes to get home on that 10 mile trip.
I know that temperatures above 210-220 F will start to leave varnish and lead to failure when done regularly.
So, I was surprised that the fluid never reaches a normalized level where the cooling mechanisms find a symbiosis with the temperature.
Now, here's where I'm confused. Normally, I'd say, "That's great! Heat is the number one killer of transmission fluid." And now, the curveball.
Subaru advertises their CVTF as lifetime fluid, unless you're towing. Obviously, towing must put a tremendous amount of stress on the fluid's lubricating and cooling properties.
However, Subaru Canada says that the CVTF must be changed about every 100,000 kilometers - or just over 60,000 miles. That falls in line with the major maintenance including spark plugs and other things for the boxer engines in their fleet.
I reached out to Subaru Canada about the interval. They say that because of the cold, the CVTF falls into a severe change schedule therefore requires a drain and fill every 100,000 kilometers. However, my Subaru USA booklet says it's only "severe" if you're towing for the purposes of CVTF.
So, that's where I'm confused. I would think that me being in a slightly more southern climate (NJ) is warmer (temperatures can exceed 100 F in the summer, and most of the time are 90 F or higher for June-July-August), and also get pretty cold in the winter (below freezing is expected for January-February)...
I don't tow, so that's good, but it got me thinking about the cold thermal properties of the CVTF. I've never had any type of irregular functioning of my CVT, but I'm still curious nonetheless.
My 2011 uses a "C-30" CVT from the factory fill. It takes about 12 quarts of fluid, but much of it is kept in the valve body and torque converter; as a result, if you do a drain-and-fill you're looking at somewhere around 6-7 quarts actually replaced. So, if you did a D&F at 60k miles, you've really got 50% of the fluid with 0 miles and 50% of the fluid with 60k miles still. Likewise if you did it again at 120k: 33% with 0, 33% with 60k, and 33% with 120k miles.
Modern Subaru CVT's now use CVTF-II fluid, which is green in color. It is backwards-compatible with the C-30 (blue in color). They also use a High-Torque CVT Fluid variant for their 3.6R (6-cylinder Boxer engine) and their XT (4-cylinder Turbo coupled with the FA DIT series engines). The high torque fluid is not compatible with the C-30 nor CVTF-II. There are several instances of people on the Subaru forums citing transmission failure and problems when using blends of the fluid when having the D&F done at non-Subaru shops. Doh!
I suppose the additive packages included with the proprietary CVTF are replenished which is usually a good thing, but at some point, it becomes a bad thing to replace old fluid because the fresh fluid can act like a solvent and disrupt some of the gunk otherwise encapsulated in the CVT and lead to valve body or solenoid failures, right?
I'm in the stages of buying a Subaru 3.6R next winter/spring, so I wanted to have a plan in place going forward for maintenance. I want this next car to last me a very long time. To me, these things aren't as disposable as people make them out to be. It's more than just an appliance or a thing, it becomes an extension of my very being, which is why I take great pride in doing my own maintenance and doing it properly. Not to digress from the purpose of this thread, I plan on running an OEM Subaru oil filter with Pennzoil Ultra Platinum 5w30 in it exclusively from the start.
So, does my CVTF never getting nearly up to "ideal" or "symbiotic" temperature cause problems?
Thanks, all. I appreciate your feedback.
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