Traction - or the lack of it

[opals]

I have a Long Range Dual Motor Model 3, and therefore both axles are driven. Not sure whether this makes it 4WD or not, but find that I loose traction when driving slowly up my driveway when it is covered with leaves. But unlike previous cars with "Traction Control", it never seems to bite / kick in etc.

Am I missing something, or is this just "normal" for a Tesla?

TIA

 

[Dangerous Fish]

Are you saying one or more wheels are just spinning and you're not moving forward?
Try and describe what's happening in a bit more detail if you can.
Do youknow about 'slip start' and have you tried it?

 

[opals]

On two different (steep) drives, I consistently hear tyre(s) slipping for a short period, during which speed slows. After this short period the noise stops and traction & low speed return to normal. It is a) surprising that the wheels skid at all, and b) it is very different from my previous cars (RR Sport, new Mini, E Class coupe) where you sort of heard a noise more akin to ABS breaking (but in reverse so to speak). With the Model 3 it is either gripping or spinning, with no "grabbing".

All of this is during low speed moving, and is not when I initially pull away. But will go away and read up on Slip Start ...

 

[MrBadger]

Are you still on the original summer tyres?

 

[LukeUK]

With 2WD, or 4WD with an open diff, you've got no choice but to use brake modulation to generate torque at the non-slipping wheel.

Tesla dual motor vehicles can drop the torque on a slipping axle and rely on the torque at the other axle to still move the car forward, so it's just motor control, not brake control.

In a cross-axled situation, a Tesla would probably have to use brake modulation as well.

Does anyone know if the Tesla diffs are open, limited slip/torque biasing, etc?

 

[apehest]

Open on all teslas, front and back.

 

[AndrewGR]

I’ve seen posts suggesting dual motor Teslas perform well in snow even on standard tyres. This suggests that however they do it Tesla traction control works pretty well!

 

[Dangerous Fish]

With 2WD, or 4WD with an open diff, you've got no choice but to use brake modulation to generate torque at the non-slipping wheel.

Tesla dual motor vehicles can drop the torque on a slipping axle and rely on the torque at the other axle to still move the car forward, so it's just motor control, not brake control.

In a cross-axled situation, a Tesla would probably have to use brake modulation as well.

Does anyone know if the Tesla diffs are open, limited slip/torque biasing, etc?

Not quite sure what you're trying to say here. The Model 3 Dual Motor uses torque vectoring so brakes are applied on individual wheels to control slip. As said the diffs are open. In normal circumstances, with the wheels straight and accelerating, power is fed to the front and rear motors approx. 35/65 but that will vary depending on various conditions.

In very low grip situations, all sorts of things are going on with the torque vectoring and power delivery and it can sound a bit odd at times. I have had a situation where accellerating from a standstill on a skid pan one or more of the wheels seemed to spin up and I hardly got any traction, but I put that down to a momentary software glitch, as it corrected itself shortly afterwards.

I think the main thing to bear in mind is that a Tesla or any EV may react slightly differently to a conventional car in in some situations so as long as you retain control and are moving forward, leave it to the electronics and you should be OK.

I think the OP will find slip start maybe in conjunction with chill mode and a light right foot will help the car move away without that initial loss of traction.

 

[Joelly]

I’ve found traction control pretty good, but yes it is quite a change from what you’re expecting if youre wanting to put your foot down.

 

[Rustybkts]

I have found the traction control to be amazingly good on my SR+. I can boot the car in any conditions and the power is feathered to suit grip.

My old E46 BMW M3 used to kangaroo when pulling away on slippy surfaces.

The very close control that electronics and electric motors have with regen to damp rotational speed allows for exceptional grip on slippy surfaces until the need to stop!

 

[Puma2020]

Not sure whether this makes it 4WD or not

Saw a good video on the difference between AWD and 4WD

The owner's manual, page 72, describes Traction Control.
In the Controls menu -> Driving, there is a Slip Start option. I have not needed to use it yet.

However, driving on wet leaves is something that I have experience with and that can be... challenging.
I concur with the previous posts that a lighter touch might help and also maybe try Chill mode.
I have found the traction control to do well in the snow/slush but it's still early in the season.

 

[Dangerous Fish]

Earlier this year I had the chance to compare traction between my Model 3 Performance, a BMW M240i, a tuned Alfa Gulia Quadrifoglio and a Jaguar F-Type on a skid pan. We launched from a standing start as hard as we could with traction control etc. turned on to see how each car coped with simulated snowy/icey road conditions. All cars were fitted with the tyres they came from the factory on ('summers').

It was a slightly uphill start and we timed ourselves from the start to a cone we placed about 20 meters away. The BMW and Jaguar couldn't get anywhere near the M3P times and with a lot of the attempts they were obviously struggling to get off the line. The Alfa did surprisingly well and was quite close to the M3P times even though it's RWD. AFAIK it's the only other car in our group which uses torque vectoring and it has a clever e-diff whereas I think the Jag and BMW have more conventional diffs and TC systems.

With the Model 3 there was definitely an initial surge of acceleration and then it held back as it tried to maintain traction.
I tried it in sport, chill, slip start and also in track mode so I could play with the TC and balance settings. There's not much difference when doing a hard launch, because the car generally behaves the same in that situation, but if you want to move off gently with minimal wheel spin I'd say slip start does make a small difference.

 

[NeilG40]

This might sound a bit obvious but couldn't you just sweep up the leaves?

 

[Jason71]

This might sound a bit obvious but couldn't you just sweep up the leaves?

Ooh which screen is that option on?

 

[Adopado]

Ooh which screen is that option on?

You need the bespoke frunk mounted leaf blower which feeds air to ducts in front of each wheel.

 

[Adopado]

I have found the traction control to be amazingly good on my SR+. I can boot the car in any conditions and the power is feathered to suit grip.

My old E46 BMW M3 used to kangaroo when pulling away on slippy surfaces.

The very close control that electronics and electric motors have with regen to damp rotational speed allows for exceptional grip on slippy surfaces until the need to stop!

Ditto ... it's one of the most surprising and reassuring aspects of the SR+! I had completely expected it to be a bit of a handful only having RWD but it has a feeling of being propelled forward with so little fuss that you would think it was AWD. Also today I took a heavy trailer load on a steep smooth damp slippery tarmac drive thinking that I might have to be wary of letting it get out of hand whilst still on summer tyres ... not a bit of it! Even with a cold battery level of regen it was sufficient to make a controlled descent without even needing to touch the brakes. Going up had the benefit of being unloaded, but no hint of slippage.

Mind you if you are an owner of a Model 3 Performance with 0-60 in the 3 second realm I don't think it is a massive shock that you might lose a little traction here and there!