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The shudder is the ECM telling the CVT to automatically change into a higher gear for the speed being done, thus enhancing fuel savings for the engine running at it's lowest RPM range for that given speed. This automatic high gear gives the shudder because it's really high for the speed. This high gear can not be selected in manual mode, (for sport models).

Think of it like this...like driving a manual....You go from 1st, 2nd 3rd, and up..depending on road speed. But what happens when you go from 3rd to 6th when your doing 30 mph? You will get that same shudder.

My test: 30mph 3 mile flat stretch of road. In manual mode I can only change my gearing up to 4th for the highest. But once in automatic mode I feel the CVT shudder (still at a constant 30mph) move the gear selector to manual and check the dash.... I am now in 5th gear!!..

Drop down to 4th gear in manual and 5th gear is not even able to be selected...move the shifter to automatic..shudder...I'm now in 5th.

It's software...it's taking over.
The fact that it is software is understood. But that also means it is correctable. Hoping to find the solution here among you posters to this board. Any thoughts?
 

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If (big if) it isn't solid SOA has put a ten year extended warranty on the CVT so I wouldn't worry about it.
What I worry about is that SOA is extending the warranty on the transmission. When they should be extending the warranty on the engine. Engine that are asked to labor—start from stop in too high a gear—wear more quickly. The engine's laboring does not cause the transmission to wear prematurely.
 

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Hey guys, glad I found this thread. At first I thought that I'm hallucinating, but now I'm convinced that the car jerks/kicks back during slow driving or decelerating around 10-20mph. I have a brand new Subaru Impreza 2018 5door Premium trim. I had installed a hitch and I know that kind of voids the warranty and hate to take it off to bring it to the dealer and then install it back (so I'm just dealing with the issue and hoping it will go away after the break-in period), but I'm not pulling any trailers, just a bike rack. Car was jerking even before I have installed a hitch. I have about 800mi on odometer now.
Thanks
The 'hitch' should have absolutely nothing to do with the issue being discussed in this thread. The TCM has torque sensors. The CVT should just choose lower gearing to address the added weight. As long as you don't over do the trailer thing. Maybe you are just carrying bicycles in your receiver hitch.
 

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If you install a hitch for the purpose of a BIKE RACK, this is a non-issue. People with Subaru's do it every day without issue. Just another case of an idiot dealer...they really need to crack down on their dealer network!
Agreed! Problem is that the Dealer / Manufacturer relationship is Federally protected, in favor of the Dealer. Thanks to Henry Ford and his shenanigans.
 

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The shuddering goes away as time goes on. I believe it is just from breaking in the transmission.
There should never be any shuddering. The boxer engine is naturally harmonically balanced. The only reason there is shuddering is that the transmission is causing the engine to work at too low RPM. This shuddering is likely more pronounced in engines have a manufactured harmonic balancers that are coupled to CVTs.
 
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