Thanks, @Bullwinkle, for this interesting information!
I think that is right. Too much may be especially bad. Makes sense that in conserve mode, the fronts do the work.
I don't understand why so many refuse to do this. It's by far the best way to understand how your vehicle will react to different situations, especially snow/ice. I've done this any time I'm driving though inclement conditions.
I started the thread when my 23 RS1 started sliding last week. My winter tires were not on, but it was disconcerting to have regen start a slide. I was going slow and could not tell if there was antilock action.
It's surprising at the difference between full traction control and reduced, as far as acceleration is concerned. It's almost difficult to get the car sideways on ice with it fully on. My K02s on the R1T were actually a bit better than the 21s on the R1S.
As a driver of several manual cars on the hilly VT winter roads I learned on growing up, I’ll have to respectfully disagree—sure, you can induce traction loss by downshifting if you quickly engage the clutch without rev matching/double clutching to match your transmission and engine to wheel speed. This can even be an intentional drift technique to intentionally induce oversteer and initiate a slide (alternative method to the Scandinavian flick or e-brake application).
Engine braking in low traction is definitely a skill, but in my experience, unless you’re really in the wrong gear (too low), it’s mostly the moment you downshift (and how smoothly you do so) where traction loss can occur as the engine speed equalizes with the wheel speed through the transmission (when RPMs are lower than wheel speeds at a new gear ratio, a decelerating force is applied to the wheels through the driveline as the engine is forced to catch up to the faster RPMs). If you’ve accurately rev matched and double clutched your downshift (so you aren’t relying on the synchros to equalize engine/transmission with wheel speed), then the engine is spinning at the right RPM for wheel speed in the lower gear when the clutch is re-engaged, resulting in much abrupt or sudden deceleration of the wheels, which is what can induce a slide. But I digress… and the skills and techniques involved with driving a manual transmission well in winter conditions are definitely increasingly niche (or irrelevant) ones (especially on an EV forum ?), though I feel fortunate to have at least learned these things towards the very end of the era where manuals were at all common (but well after they were “standard” even though I still sometimes call them that).
Great post, fun read--the call to action for Rivian is this and they should do it! I'd settle for 20% increments ;-)
This is a profound recommendation for most folks reading this that encounter icy roads. The only way to learn how to get a specific vehicle back in control when it has lost traction is to get it a bit out of control a bunch of times in a safe place. Muscle memory is real.
