Over Donnor Summit, CA with M3 AWD during a chain control

[DonTom]

When there is a chain control over Donnor Summit (CA I-80, 7,240' elevation) when they say it requires "chains or 4WD with snow tires" as they do right now, will my 2018 Tesla M3 dual motor with the stock tires be allowed to go over without chains?

-Don- Auburn, CA

 

[Misterbee]

No, because the stock tires are not snow tires. Also, it would be a very bad idea.

 

[DonTom]

No, because the stock tires are not snow tires. Also, it would be a very bad idea.

"All Terrian" tires (but not the "all-weather tires" ) count as snow tires over the summit, such as the ones on my 4WD Jeep (which is now not here with me). Are there all-terrain tires available for the Tesla M3?

 

[Earl]

"All Terrian" tires (but not the "all-weather tires" ) count as snow tires over the summit, such as the ones on my 4WD Jeep (which is now not here with me). Are there all-terrain tires available for the Tesla M3?

That kind of shows the subjectiveness of the requirements since many All Terrain tires are terrible in the snow. Only those that are "all-weather" or "snow" rated are generally the exception.
I've known of plenty of Model S AWD folks who have been waived through on I-80 with stock all-weather tires but that doesn't mean everyone will.

 

[vlee]

There was a break in the snow yesterday so I drove east from Sac to Reno last night. The road was dry (no snow or water), so the stock all-weather tires were mostly fine. There was no chain control at that time. However, there was a 100ft patch of black ice which my tires slipped on. Luckily, I wasn't turning or braking at that time, so nothing bad happened. However, it appeared to have caused a truck to slide off into the side guardrail. Later in the evening around 9pm, it looked like two more trucks had spun out and blocked the road (based on Caltrans QuickMaps).
If you live in Auburn, getting an additional set of wheels with snow tires would be a great investment. You could swap them out with your regular tires easily in your garage with a jack.

 

[ucmndd]

For the purpose of California chain controls any all season tire marked with “M+S” (mud + snow) or the 3PMS symbol are considered “snow tires”.

Most all-season tires meet this threshold. I can’t say for certain that all OEM tires for Model 3 do, but the Michelin MXM4 definitely does.

3PMS symbol:

 

[STS-134]

When there is a chain control over Donnor Summit (CA I-80, 7,240' elevation) when they say it requires "chains or 4WD with snow tires" as they do right now, will my 2018 Tesla M3 dual motor with the stock tires be allowed to go over without chains?

-Don- Auburn, CA

The official chain control requirements are here: Chain Controls / Chain Installation | Caltrans

Snow-tread Tires: The California Vehicle Code, Section 558 defines a snow-tread tire as follows, "A 'Snow-tread tire' is a tire which has a relatively deep and aggressive tread pattern compared with conventional passenger tread pattern". Snow-tread tires can be identified by examining the sidewall of the tire where the letters MS, M/S, M+S or the words MUD AND SNOW have been stamped into the sidewall.

M+S tires are commonly referred to as "all-season" tires. They are not dedicated winter/snow tires. The stock tires (assuming it's a non performance model) have M+S stamped into the sidewall, so they meet the requirements of a "snow-tread tire" under the CVC, provided that they have at least 6/32" of tread on them.

The 3 levels of chain requirements:

• Requirement 1 (R-1): Chains are required on all vehicles except passenger vehicles and light-duty trucks under 6,000 pounds gross weight and equipped with snow tires on at least two drive wheels. Chains must be carried by vehicles using snow tires. All vehicles towing trailers must have chains on one drive axle. Trailers with brakes must have chains on at least one axle.
• Requirement 2 (R2): Chains or traction devices are required on all vehicles except four-wheel/all-wheel drive vehicles with snow-tread tires on all four wheels. NOTE: (Four-wheel/all-wheel drive vehicles must carry traction devices in chain control areas.)
• Requirement 3 (R3): Chains or traction devices are required on all vehicles, no exceptions.

So yes, if there are R-2 chain requirements in effect (what you have described), a Model 3 AWD with the stock tires or any all-season tire with M+S on the sidewall will be allowed to proceed without chains. It will also be allowed over the summit under R-1 chain controls. Note that there is an R-3 chain requirement on the books though, and if that gets imposed, everyone has to chain up. Also note that whenever any sort of chain requirement is in effect, the speed limit is 30 mph and you must carry chains even if you aren't using them. This is so if you get stuck, you can get out of the ice by chaining up, because M+S tires or even 3PMSF or dedicated winter tires aren't going to give you the same traction as chains digging into the ice.

 

[AMPd]

That kind of shows the subjectiveness of the requirements since many All Terrain tires are terrible in the snow. Only those that are "all-weather" or "snow" rated are generally the exception.
I've known of plenty of Model S AWD folks who have been waived through on I-80 with stock all-weather tires but that doesn't mean everyone will.

Yeah those dudes up there aren’t really checking, I was waived through in my P90D with 21in summer tires.

 

[scurtis]

I have michelin alpins on my m3p. Works like a dream. If I lived in a very icy place, nokian makes a good studded winter tire too.

 

[Watts_Up]

The 3 levels of chain requirements:

• Requirement 1 (R-1): Chains are required on all vehicles except passenger vehicles and light-duty trucks under 6,000 pounds gross weight and equipped with snow tires on at least two drive wheels. Chains must be carried by vehicles using snow tires. All vehicles towing trailers must have chains on one drive axle. Trailers with brakes must have chains on at least one axle.
• Requirement 2 (R2): Chains or traction devices are required on all vehicles except four-wheel/all-wheel drive vehicles with snow-tread tires on all four wheels. NOTE: (Four-wheel/all-wheel drive vehicles must carry traction devices in chain control areas.)
• Requirement 3 (R3): Chains or traction devices are required on all vehicles, no exceptions.

Would chain still be required if you have studded winter tires ?

 

[scurtis]

Would chain still be required if you have studded winter tires ?

I'm not from cali, but I've heard that if r3 is on, basically road is closed. If it's r1/r2 sounds like you still need to carry chains. Seems kinda redundant to me. I think they treat studded tires as snow tires.

 

[STS-134]

Would chain still be required if you have studded winter tires ?

Studded winter tires count as snow tread tires. Requirements are the same as with 3PMS and M+S tires: If the chain control level is R1, chains are not required. If the chain control level is R2, and you have 4WD/AWD, chains are not required, but if you do not have 4WD/AWD, chains are required. If the chain control level is R3, there are no exceptions, and you must chain up.

I'm not from cali, but I've heard that if r3 is on, basically road is closed.

I've seen R3 imposed once. Road was open, but even 4WD/AWD vehicles with snow tread tires had to chain up.

If it's r1/r2 sounds like you still need to carry chains. Seems kinda redundant to me. I think they treat studded tires as snow tires.

It's not redundant. If you get stuck, you'd better have chains with you so you can put them on and get unstuck.