cvt paddle downshift to aid stop?
I'm coming from a manual 6-spd for 8 years and a 5-spd for 4 years before that just fyi. I like how the cvt can be shifted with the paddles even in drive mode and then just returns to normal auto drive on its own. Seems very useful for a highway pass; downshift for some more power, make the pass and be on your way without fiddling around. But I'm also finding myself wanting to shift down a click or two when stopping as I'm used to having that gearing help in addition to the brakes. Just wondered if anyone else does this, or if I should stop this habit in case I'm better off just wearing out brakes and avoiding any type of transmission issues this could cause (if any?). Anyone know for sure if this could be damaging? My thinking is the electronics aren't going to let it go too low and I'm not talking about racing into every stop and letting the gearing whine...but I do notice less braking force required even with conservative speed into a stop. Thoughts?
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I use them all the time...especially when towing my teardrop
I also use them for early upshifts to save fuel. I don't need to peg 3000 rpm every time I accelerate.
Soon2b, that trailer is rad.
Soon2b, that trailer is rad.
2013 Satin White 2.5 Limited w SAP, Puddle Lights, Rear Seat Back Protector
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They are great for downshifting coming up to a light. As long as you don't put your foot back on the gas, it will not go back into "D". I, quite frequently, down shift through several "gears" as I'm coming up to lights.
The other neat thing is that the car will us engine braking to attempt to hold the speed the cruise control is set to on steep downhills.
The other neat thing is that the car will us engine braking to attempt to hold the speed the cruise control is set to on steep downhills.
I'm not a mechanic so I can't address if it's bad for the CVT but as was pointed out, if Subaru didn't want you to do that then why provide the capability. I use the downshift on a descending hills to save on the brakes. It's a great feature of the CVT.
I use 'em for going down grades. Not so much for general stopping. Brake pads have got to be cheaper than the wear items inside the trannie. Plus, you can just lift off the gas sooner, save gas, as well as brake pads. But that is just me.......
Brake pads are cheaper than a transmission.
That is the correct way to use the tranny. This has been discussed before in great length. Anyone who downshifts all the time to slow the vehicle (Auto or Stick) is a fool. Going down long grades is another story. Brakes are cheap, clutches and trannys are not.
I'd like to see some of the researchers tackle CVTs as well. These are built to shift a bit more often than your normal geared transmission, lack a clutch in many cases, and in general wear differently than a geared transmission. While I agree that any shift will provide wear, I don't think we can blindly apply geared transmission logic to belted/disc transmissions.
For example: I can't tell someone to not do this because it will burn out the clutch, since in the case of the Subaru CVT, it uses a torque convertor which is going to see the same wear regardless of what the transmission is doing (in the general case, anyways).
Unlike a geared transmission, the CVT is constantly adjusting up and down anyway so maybe it doesn't make a difference.
I know this has been discussed here previously.
Let's see if we can find out more about this on the web.
Good discussion.
I know this has been discussed here previously.
Let's see if we can find out more about this on the web.
Good discussion.
A CVT transmission is constantly "shifting" anyway.
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Down hill speed check down shift is actually a good idea especially with the CVT given its pretty slippery and the car will just rocket down hill unchecked.
Driving around town and down shifting as you approach stoplights? Brakes are a better idea cost less to service than a CVT and even the MT folks say down shifting past 3rd for regular use around town stuff is just shocking the running gear hard and adding wear to the transmission - and drive lines which really isn't worth the value add going below 3rd.
Driving around town and down shifting as you approach stoplights? Brakes are a better idea cost less to service than a CVT and even the MT folks say down shifting past 3rd for regular use around town stuff is just shocking the running gear hard and adding wear to the transmission - and drive lines which really isn't worth the value add going below 3rd.
Exactly. FWIW, Most people don't keep their cars for the long haul anymore so they typically do not care.
All transmissions are designed to deliver power in one direction.......Slowing the vehicle is a secondary provision. With the CVT, it may not make a lot of difference which way the strain is going. But it very well could be that it is much more rugged in the power on direction.
Also, torque convertors are directional as well. Many auto trannie failures actually start as torque convertor failures. (When bits start to break loose, they go all through the transmission. In general, any major work on a trannie includes a torque convertor replacement.) Driving the motor with the car is not what they are designed to do. Just sayin'.
Again, brake pads are relatively cheap, and easily replaced. If you want to save your brakes, plan ahead, just take your foot off the gas sooner. Try it. You will be suprized how little you will need your brakes.
I did not put brake pads/shoes on my 4runner until it had 180k on it. Manual trannie, but I don't downshift it to slow, either.
Don't get me wrong, I don't actually do a lot of engine braking, just on long hills, and I'm pretty gentle on the brakes when I can be (traffic sometimes decides otherwise). I'm just wary of applying "common wisdom" on a fundamentally different transmission design without some data to back it up. I'd agree that in the absence of such data, that caution is probably due, but that's different from assuming the same rules apply, and using that as the reason for doing it that way.
Torque being applied in the "wrong direction" leading to additional wear makes some sense, depending on the design of the components. While it only needs to work in one direction, that doesn't mean that the design will wear out faster in the other, but it could. But the downshift itself shouldn't be the reason for the additional wear in a CVT design, not when the torque convertor should still be locked up through the whole engine braking maneuver.
Again, this is why I'd wish there was better data on it to research.
Anytime you drive your car there is wear and fatigue occurring in the drivetrain. It is hard to dispute that downshifting will increase that wear and fatigue. The question is weather it will cause a problem in your ownership period. Maybe, maybe not. It is still not a good practice unless necessary.
Many trucks with a tow haul mode use the motor to slow down by design. Subaru built some characteristics into the CVT to do this as well. I think engine breaking on grades to hold speed is fine myself. I don't think I'll be doing it to stop lights however.
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