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2015 Subaru Outback CVT in freezing weather

In below freezing temperatures the CVT transmission in my 2015 outback will not adjust to the normal ratio causing the engine to run 500-1000 rpm faster than normal for the 25-40 mph speed for the first five miles or so until it warms up. This didn’t occur when the car was new but has for the past 25-30,000 miles, it now has about 60,000 miles. Is this typical or something I need to be concerned about?

I would start by a transmission fluid service.

You’re a patient fellow. I would have taken the car to the dealer the first winter it occurred and hoped it was a warranty or goodwill warranty repair. I would still take it in immediately, it’s only 4 years old, they may fix it at their expense. We have an Outback one year newer than yours and Subaru has extended the warranty on our transmission to 100K miles.

Agree with the fluid change but take a look at the several discussions on fluid changes and CVTs, the jury is out but why take a chance? I will have to say that in very cold temps it was not unusual for my car to not shift into overdrive until it was sufficiently warmed up. I’m talking below zero. I don’t remember now but there was some type of temp sensor involved. Five miles is nothing in the cold. Sometimes it would be ten miles on the interstate to get everything up to proper temp.

My 2014 Legacy does the same thing and has done so since new. Actually 45 degrees F seems to be the dividing line. It’s like it has a different shift profile when the IAT is 45F or lower for about 5 miles or so. The it begins to follow the normal ratios.

Several posters to the forum and those for other makes report similar problems, most attributing it to long transmission fluid warm up times. But this doesn’t explain not having the problem when new - let’s hope that it’s just aged fluid but other components also might be an issue, so get it in to the dealer (to see if they have an TSB, or advisory, or an extended warranty on it, or other ideas) and, lacking any help there consult a good transmission shop (in Car Talk’s Mechanics Files).

There’s a TSB for CVT controls addressing rpm flare and cruise control operation. 16-99-16. Might want to take a look at that. Involves some CVT reprogramming I think. Appears to happen only in cruise control applications, but still might provide a clue.

Just in case you find it helpful when dealing with Subaru, your Outback’s CVT warranty has been extended for your vehicle. Up to 100K miles. You can find details of that here at our partner site. Just FYI, you also hit the “Jackpot” on the engine extended warranty program that covers excessive oil consumption/engine failure. You can read about that right here at CarTalk. These warranty extensions are helpful if you opt to trade or sell your car before 100K. And you’d be crazy not to.

I believe they do have it when it is new, they just don’t notice it. I think the most people, like me, are experiencing their first CVT. I bought mine around Christmas so I didn’t know what to expect RPM wise. In fact, compared to the previously owned vehicles I had, even with the “cold program” the engine ran at lower RPM’s. It wasn’t until I went through a summer and got used to the programmed ratios that I noticed the difference when the IAT was 45 degrees or lower.

My transmission was one of those that had the defective solenoid in the throttle body and the throttle body had to be replaced at around 58k miles. That got me a fresh ATF change and the transmission reprogrammed. Nothing changed, first time the IAT went below 45F, the ratio program changed.

Not to start any conspiracy theories or finger pointing, I think this is done to warm the engine up quicker to meet smog laws.

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