My Wife bought a 2019 Subaru Ascent in Sept. It has 16000 miles on it. In the last few months she is getting odd noised from it. I have only heard it once, hard to reproduce.
I experience this yesterday as a passenger.
A squealing sound. Sounds like a traditional belt squeal that you would get from older cars. Sound coming from under center console.
RPMs jumping about 500 RPM very quickly. Up and down. I was watching the tach.
Car ‘lurches’ as this is happening. We where going about 50mph.
Oddly (info from my wife) this happens on flat ground uphill and downhill.
My Wife has taken it to the Subaru dealership, but since they could not reproduce it, they sent her on her way. It’s time for me to get a bit more involved.
I believe that the belt on the CVT is sometimes slipping. Perhaps the belt is defective or the pressure regulator for the conical pullies needs to be adjusted (if possible, haven’t a clue)
I’ll be calling the dealership tomorrow. The dealership is 100 miles away, so it’s a bit of an issue going there and just having them shrug their shoulders.
I would like to test to see if you lock it in a particular ratio when this happens if it clears it up. I think that would be a good test. But again, it’s very hard to reproduce. We just went on a 1400 mile road trip, and it didn’t happen at all.
All I can offer is a data point for comparison. We have both a Legacy and a Forester, both from 2014 and both with CVT. Never had the slightest problem with the transmissions. Very happy with how they drive. What you described is definitely not normal.
How about temperature? When this happened was it after a long ride or a short ride? Was outside cold or hot? Stop and go traffic and highway?
All those will affect the temp of the engine and transmission. I don’t know the material for the belt, but possibly when started from cold the belt will be “tighter” and if you are in traffic where the belt is sliding up and down the cones, it’s getting hot therefore expanding a slight bit and slipping.
I’d also note at what speed this happens. Any speed, a particular speed (like 65mph) or just random.
I’m thinking towards temp though. Highway speed probably won’t do it as you have good airflow and the belt will more or less bein one spot.
What I’ve heard about some CVT’s is when the belt slips it cuts a grove in those cones, which makes it far easier to slip again. The first time could be a high torque situation but it will continue much less stressful situations. CVT’s are not perfected technology.
The new Subie CVTs are trash, sorry, full of plastic parts and notoriously difficult/expensive to fix. Any of the owner boards will bear that out. But this is a warranty repair, the sweetest words in English Tell the dealer what’s going on and let them figure it out. Chances are you’ll get a new transmission. Don’t leave without a loaner, and don’t own an out-of warranty CVT.
Well your car has plenty of warranty left to figure this out. See if you can reproduce the conditions that make the problem apparent to the casual observer. Maybe it’s in only certain gears or speed that it occurs.
Once you nail that down ask the dealer if they can keep the car for a day or a couple of days and give you a loaner so they can drive it around and hopefully see what you are talking about. I know it’s a pain since the dealership is far away but I have a Subaru and they did that for me when my car had a problem that only occurred sporadically and eventually they were able to reproduce the problem and repair it.
The new CVT is why I opted to not buy another Subaru Forester after having one for 10 years and 170K miles (my wife’s lasted 250k on the original manual transmission). Not only are the CVTs inconsistent (just google it), I was really turned off by Subaru’s reaction to instances of stalling at highway speeds. Instead of issuing a recall and proactively fixing the transmissions before issues start, they took the wait and see approach, and just extended the warranty. This “kick the can down the road” attitude really annoyed me. Also, for such a renowned brand, they took too much time before dipping into the electric world. I expected a hybrid Forester 5 years ago, but instead they (finally) put it in the more expensive Crosstrek. The Forester is still gasoline-only. Really bad marketing decisions here.
We are wondering about temp too. But it did not have any problems at all when driving on a 1200 mile road trip to Arizona. One day is was 100 degrees. Where it does happen is at our house in the Colorado Mountains which is decidedly colder. We are still getting snow.
We don’t drive in traffic. All of this is 40 plus mph.
Wife says it doesn’t matter if it going up hill or down hill. So it does not seem to be over stressed. A VERY odd consideration is that this only seems too happen at altitude. Over 9000 feet.
I think there must be something wonky with what ever regulates the pressure of the conical disks that makes up the pulleys.