Traction Control Behavior Changes

Traction Control Behavior Changes

I've commuted on a 4 lane mountain road for 2.5 years. Hundreds of trips. It's about a 10 mile ride.

It's a blast in the Model 3. Several hair-pin turns, how fast can I take them?

Pretty fast until about a month ago. On a couple of turns for reasons I cannot figure out, traction control started kicking in. The yellow icon flashes, the brakes pulse rapidly on 1 or more wheels, the car slows a bit. Might last up to 1 second.

Today, it was really bad. The car swerved a bit and slowed by 10 mph. I was concerned that the guy behind me would be startled and react (didn't, fortunately).

I have 2 hypotheses:
- I recently changed out the rear tires, though it's the front that get the traction control action.
- I recently had a software update that in theory could have included a change in the traction control behavior.

Any ideas? Is anyone else seeing this?


FISHEV | September 19, 2019

Only thing that makes sense is the new rear tires are pushing the old front tires and the front tires lose traction.

WantMY | September 19, 2019

AWD is very finicky with tires and wear. I avoid AWD for this very reason, when possible. FISEV offered a pretty good guess.

Tronguy | September 19, 2019

Watch it- Fish and Want are both known astroturfers.

jrweiss98020 | September 20, 2019

Traditional AWD may be "finicky" with tires with unequal wear, because the center differential has to continuously contend with the disparate rolling circumferences of the new vs old tires. Since the front and rear axles are independent on the Tesla, that should not be a factor.

OTOH, the new tires may have WAY different traction than the old ones. Brand-new tires may actually have LESS traction than half-worn tires on dry roads. It's possible that the rear tires are actually breaking loose first. I don't know how the TC is programmed, but possibly it's braking the tires with most traction in order to slow the car. Braking the rears would more likely induce a skid if they are already slipping.

You might try swapping the new tires to the front...

cdiamond | September 25, 2019

Always put the new tires on the front.

texxx | September 25, 2019

@cdiamond - Not according to Discount Tire

wayne | September 25, 2019

I’d replace the other two tires with new ones. Why go halfway?