[TeleRisk18]

Cold start; Frist 1 or 2 stops short distance from where I started; downshifts are noticeable. After that you can barely feel any downshift. The way it is?

 

[yticolev]

The clutch is a dry clutch, similar to most manual transmission cars. I don't remember any differences over the years between cold start clutching and after the engine has warmed up. While the Niro has a dry clutch, the mechanism is shifted with a hydraulic system. This could be sensitive to cold causing either slower than normal shifts, or more of a bang into gear. In my brand new Niro, all my shifts so far, cold or warm, are very smooth.

Most motorcycles on the other hand have wet clutches, usually a shared engine oil arrangement. This is true whether manual transmissions or DCT (not sure about other transmissions). Their action would be temperature dependent. Some cars may have a wet DCT as well. I believe the Honda Fit Hybrid (not sold in NA) has one.

 

[TeleRisk18]

Thought I would bring this up again.....2018 Kia Niro EX.

I still continue to experience abrupt downshifts after vehicle sits unused for 2 to 3 days during my stops in my 1st 1/4 of travel. If I drive car daily, no issues. Its like, fluid pressure escapes (if in fact shifts are Hydraulic driven). Transmission is full per the reservoir. You wouldn't associate an issue like this from a bad part....it would happen if it where a part daily.

 

[yticolev]

The engine clutch is indeed hydraulic actuated. Requires fluid change at 22,500 miles. Very small capacity, so a small amount of contamination could cause lurching with inconsistent clutch application. Not sure why they didn't design it with a reservoir. If you look under the hood, you will find the fill tube.

 

[TeleRisk18]

Contacted the Service Mgr at the Kia Dealer to inquire if he had any knowledge of the Cold Downshift issue. He had not, he did mention the Shutter issue many owners of this model have reported, but not the Abrupt cold downshift issue I have been experiencing. He reviewed all Factory Bulletins, and just so happened the Kia Factory Agent was in the shop....and he hadn't heard anything either. The Service Mgr was prompted from Shp Forman....and had worked on Niro's. Speaking out loud he said, can't be Fluid (I thought the Canister you see was also the Fluid level for Transmission, its only for the Hybryd system)..and no way to visibly see Transmission Fluid level...without opening Transmission...but he said, if that were the cause, the Downshift would continue even after a few stops... He mentioned a Solenoid that I think he said controls Gears 1 and 3 shifts...but no explanation if that were so why after 2 or 3 Cold Downshifts, or, using the car everyday...the Cold downshift issue was not present. Again, if the car sits unused 2 to 3 days or more, the Cold Downshift, the last downshift before coming to a stop is very abrupt (Serviced Mgr said that was shift from 2 to 1). The Solenoid is Internal and means a Teardown... not sure I would opt for that...rather I would either make sure I drive car everyday, even if just around the Block, or just put up with the issue. I have not had good luck getting issues with cars resolved when a Major teardown...was required to fix an issue....even to the extent of making the issue worse, or, causing new issues. Other than this cold downshift issue, I really like the Niro...I average 48 MPG, its nice ride, well built vehicle. I just feel like this is the saying, let new technology have a few years to get out all the bugs before buying. I do Plan to trade in 3 yrs....so holding off any Major teardown.... I have 2 yrs to go.

 

[yticolev]

Jerky downshift when cold? My Niro does it too, and so do lots of other cars. Don't worry about it, not a defect.

 

[FlNiro]

Jerky downshift when cold? My Niro does it too, and so do lots of other cars. Don't worry about it, not a defect.

Yes, it's just the way it is. I'm used to it now. Goes away very fast.

 

[TeleRisk18]

When I start out cold from my garage, I have fairly short distances for my first few stops....so maybe 3 stops in 1/4 mile....than the shift is fine. Hearing that others are now experiencing this abrupt Downshift for few stops starting off cold....I wonder why Kia hasn't heard of this issue even to just say it is just the way it is. The Trany needs tweaking thats for sure; my other Hybryd links the engine with a CVT Trany...its as smooth as butter. So the plus is on the Dual Clutch; no Torque Convertor which will keep MPG down....or the Dual Clutch that has some strange shifts. Sometimes I feel like my Niro is looking for a shift and needs me to apply a little more speed to accomplish that shift.....the idea on Dual Clutch certainly is a Plus to increase Gas Mileage, but it needs to work and refinements. If I get any thing new from the Dealer I'll report back....not that it makes it better, but its always a little relief when you find out your not aslone, others are experiencing the same issue....

 

[TeleRisk18]

Posting it is not a defect; because others have reported here, or, told so by a Kia Niro Service Tech?

 

[jmurphEV]

Posting it is not a defect; because others have reported here, or, told so by a Kia Niro Service Tech?

More likely because it's a not unexpected behavior. Hard shifting when cold is common for basically every type of transmission, manual, conventional automatic, dual clutch autos, you name it. In fact, I would expect DCTs would be particularly susceptible to this sort of thing since they are conventionally clutched (no torque converter to soak up shocks) and hydraulically operated making them strongly dependent on fluid temperature.

 

[yticolev]

The Niro DCT is electrically switched, no hydraulics. Nor is it a wet clutch which might also reduce the impact of a cold downshift. The engine clutch is hydraulic.

 

[jmurphEV]

The Niro DCT is electrically switched, no hydraulics. Nor is it a wet clutch which might also reduce the impact of a cold downshift. The engine clutch is hydraulic.

Fair, but my point remains, a conventionally clutched transmission lacks the shock absorbing ability of a torque converter. In addition, geared trannies in passenger vehicles almost always use synchronizers to match shaft speeds when shifting, regardless of how the shift is actuated. Syncros are operate via friction and so are strongly dependent on the properties of the lubricant which is a function of temperature.

I stand by my contention that basically every transmission type is affected by temperature so it's not surprising that the DCT in the Niro might shift hard in the cold.

 

[TeleRisk18]

Right or wrong, Good or bad....I just do not like the feel of those first few cold Downshifts; especially the last one which to me is abrupt...I think the dealer referred to it as 2nd to 1st gear. So for the past week I have experimented as I am coming to a stop at about the point of the start of downshifts, I put the car in Neutral and when I come to a complete Stop, shift it back into Drive. After a few stops, I leave it in drive and downshifts are normal.....

This is an area Kia needs to tweat as well as the shifting points which sometimes the shift into a lower more economical Gear could be sooner. But averaging 48 MPG....that's the goal of driving a Hybryd.

 

[yticolev]

In addition, geared trannies in passenger vehicles almost always use synchronizers to match shaft speeds when shifting, regardless of how the shift is actuated. Syncros are operate via friction and so are strongly dependent on the properties of the lubricant which is a function of temperature.

Well, there certainly is oil in the transmission. So perhaps synchro function is the key to cold downshift issues. Thanks for that, I've have been trying to figure out how that happens. I kept going back to a now irrelevant question of why the dry DCT clutches would operate differently when cold.

 

[jmurphEV]

I kept going back to a now irrelevant question of why the dry DCT clutches would operate differently when cold.

Yeah, when you start to think about it, these things are devilishly complicated and it's surprising they work as well as they do.