Snow driving - Traction Control over-aggressive!!

[afeudale]

Hey guys,

2020 M3 SR+ here. Love everything about the car so far, except:

Just had a pretty significant snowfall here in Toronto yesterday and I noticed the car pretty much disables acceleration entirely when starting from a stop.

I have proper winter/snow tires on the car, so traction should be decent.

Almost got into two accidents because of this - making a right turn from a side-street stop sign onto a main road with the oncoming car at least 3 blocks away. M3 made the turn soooooo excruciatingly slowly that the oncoming car was already on my tail.

This is *not* an exaggeration! Took probably 10-15 seconds to complete one single right-hand turn!

Turning on slip-start seemed to help a bit, but really, this is very concerning. Any ideas?

 

[holmgang]

Hey guys,

2020 M3 SR+ here. Love everything about the car so far, except:

Just had a pretty significant snowfall here in Toronto yesterday and I noticed the car pretty much disables acceleration entirely when starting from a stop.

I have proper winter/snow tires on the car, so traction should be decent.

Almost got into two accidents because of this - making a right turn from a side-street stop sign onto a main road with the oncoming car at least 3 blocks away. M3 made the turn soooooo excruciatingly slowly that the oncoming car was already on my tail.

This is *not* an exaggeration! Took probably 10-15 seconds to complete one single right-hand turn!

Turning on slip-start seemed to help a bit, but really, this is very concerning. Any ideas?

Possibly lower the pressures on the rear? Or add weight via sandbag or other in the hidden trunk compartment?

 

[alsetym]

Hey guys,

2020 M3 SR+ here. Love everything about the car so far, except:

Just had a pretty significant snowfall here in Toronto yesterday and I noticed the car pretty much disables acceleration entirely when starting from a stop.

I have proper winter/snow tires on the car, so traction should be decent.

Almost got into two accidents because of this - making a right turn from a side-street stop sign onto a main road with the oncoming car at least 3 blocks away. M3 made the turn soooooo excruciatingly slowly that the oncoming car was already on my tail.

This is *not* an exaggeration! Took probably 10-15 seconds to complete one single right-hand turn!

Turning on slip-start seemed to help a bit, but really, this is very concerning. Any ideas?

Was out and about in the hammer, I drag raced awd trucks, SUVs and a Subaru. Slowest races ever, but won every one of them with my rwd with snows. Did you see anyone accelerating faster? It was VERY sloppy yesterday mate. My experience is that Tesla's traction control is one of the best in the business in terms of finding something to grip. It just doesn't allow you to make rooster tails lol.

 

[thatgeekinit]

I took my M3 AWD out in the recent CO storm (really just trying to get home on I70 on Friday) and I was a bit disappointed in my new snow tires too. I was expecting it to be equal or better to my 2004 BMW 325xi given similar weight and size.

Switching to Acceleration = Chill and Regerenerative Braking = Low helped but I definitely had to hit the SlipStart (turns off traction control) a few times.

It might be that the tires were too new and also I found that the tireshop could have added a bit more pressure (39-41 cold). TireRack says that the cold tire pressure should actually be a 2-3PSI higher than the sticker in the car for snow tires so I pushed them up to 44.5 and hopefully that helps.

 

[afeudale]

Possibly lower the pressures on the rear? Or add weight via sandbag or other in the hidden trunk compartment?

That's a good idea, thanks! I think my pressures are a bit high from the tire shop. What do you recommend for fronts/rears? Standard aero wheels on it.

 

[afeudale]

Was out and about in the hammer, I drag raced awd trucks, SUVs and a Subaru. Slowest races ever, but won every one of them with my rwd with snows. Did you see anyone accelerating faster? It was VERY sloppy yesterday mate. My experience is that Tesla's traction control is one of the best in the business in terms of finding something to grip. It just doesn't allow you to make rooster tails lol.

Thanks! Yeah, everyone was accelerating faster. I'm also coming from a long lineage of RWD manual trans. cars over the last 20+ years (last one a BMW 6-series) and would definitely have been much faster than the M3 was doing!

 

[afeudale]

I took my M3 AWD out in the recent CO storm (really just trying to get home on I70 on Friday) and I was a bit disappointed in my new snow tires too. I was expecting it to be equal or better to my 2004 BMW 325xi given similar weight and size.

Switching to Acceleration = Chill and Regerenerative Braking = Low helped but I definitely had to hit the SlipStart (turns off traction control) a few times.

It might be that the tires were too new and also I found that the tireshop could have added a bit more pressure (39-41 cold). TireRack says that the cold tire pressure should actually be a 2-3PSI higher than the sticker in the car for snow tires so I pushed them up to 44.5 and hopefully that helps.

Thank you! Good ideas - I will change the acceleration and regen as well to see if that helps.

 

[GtiMart]

Same here. M3 AWD with snow tires in Quebec City, a lot of snow and ice. Traction control and stability are a bit aggressive in my opinion. My previous WRX was a little bit looser and more fun. The "traction mode" was great too, removed the traction system and made the stability more permissive. Was a great mode. I tried slip start and it's not as good.

Traction in the m3 is great on wet asphalt, that sort of thing but on very slippery surfaces like ice we need an "advanced driver" mode. Maybe not track mode but something that reduces the assistance. I would love for that to ve saved in the driver profile.

 

[GtiMart]

Ah, another comment after re reading some messages. On a straight line the traction system isn't bad. It's when you're turning at the same time that power cuts too aggressively. I think the car doesn't want to slip sideways at all. That makes it push (understeer) a lot. Letting the back slip a bit while turning would help a lot make the car more neutral on very slippery conditions and maybe make it merge a bit faster in traffic as OP mentions.

 

[Park2670]

Agreed on this. LR RWD on XIce tires. Came from driving many RWD BMWs. This one really takes away the fun and I have to give myself a LOT of room compared to what I am used to in my previous cars. Even with Slip Start on, it really does not like the car to get much rotation.

 

[dsgerbc]

I finally got to test my P3 in some snow on proper rubber. I agree that traction control leaves zero room for play, and I can see how it could be a problem in a RWD car. Track mode is pretty fun in the snow tho.

 

[dsgerbc]

Also, what are OP's winter tires exactly and how many miles on them?

 

[afeudale]

Ah, another comment after re reading some messages. On a straight line the traction system isn't bad. It's when you're turning at the same time that power cuts too aggressively. I think the car doesn't want to slip sideways at all. That makes it push (understeer) a lot. Letting the back slip a bit while turning would help a lot make the car more neutral on very slippery conditions and maybe make it merge a bit faster in traffic as OP mentions.

Yes, this is 100% the situation. On straight line it was ok. It was the turning that was ridiculous. It understeers like crazy and almost put me into the other lane. I was expecting a typical RWD which is to oversteer.

 

[Dangerous Fish]

The only answers for the moment are:
1. Better tyres to give you more grip and traction
2. Use slip start and/or track mode to allow more slip
3. If (2) doesn't give you enough slip, disconnect a wheel speed sensor to disable traction control
4. For RWD only, ask Mountain Pass Performance about their 'party box'

Oh, (3) is probably not a good idea, just in case you take it seriously.

 

[afeudale]

Also, what are OP's winter tires exactly and how many miles on them?

The tires are Kumho Wintercraft RP72. Only a few weeks old.

 

[afeudale]

The only answers for the moment are:
1. Better tyres to give you more grip and traction
2. Use slip start and/or track mode to allow more slip
3. If (2) doesn't give you enough slip, disconnect a wheel speed sensor to disable traction control
4. For RWD only, ask Mountain Pass Performance about their 'party box'

Thank you! Will try those suggestions as well!

 

[Icenks]

To the OP
Im in Markham, literally right beside toronto.

I got mine in dec, 2020 model and running on original tires at 45psi (the car shows 45)
I have no trouble accelerating from a stop. I used to drive a Subaru by the way, that thing drives really well on snow.

But turning on snow with all season understeers quite a bit.

 

[Dangerous Fish]

Thank you! Will try those suggestions as well!

Take my replies with a pinch of salt. The other way to prevent terminal understeer is just to back off the power and unwind the steering. Less fun but you'll get some grip back.

 

[Icenks]

Umm this car does behave differently.
My Subaru would oversteer right away if you gun it at a turn. Despite having only 175 hp.
But yeah. Agree that slow and steady gets the grip. Lol

 

[dsgerbc]

The tires are Kumho Wintercraft RP72. Only a few weeks old.

Bottom of the pile euro-winter tire. There are A/S tires that would have more grip on ice/snow.
That's your problem.

Understeering on low-grip isn't traction control issue. If you're plowing, having no TC will just let you swing the rear end around, but that won't stop your overall trajectory.