Auto-pilot horrible ping pong, something seems wrong?

[jboy210]

UPDATE:

So I took the car back to the SC, and they re-calibrated the cameras and did another alignment, but still the car oscillated on the highway.

Then they decided to change the front tires.

They said they had some new front 20” rim/tires in the warehouse, So they installed them and went for another test drive.

The result, problem solved. The SC called me, and told me that I’d have to buy 2 new front tires on the car, even though my tires had some life left on them. I agreed because I was just desperate to solve the issue.

A day later, I picked up my car and got the service invoice. Their was not a charge for the alignment, and also no charge for the 2 new tires. I was shocked. The service line said, GOOD WILL SERVICE, no charge, so that was really nice and unexpected. So immediately I drove the car on the highway and it drove perfectly, just as it did prior to me changing out the rear tires.

So my assessment is, when I changed the rear tires, but didn’t change the front tires, I inadvertently caused the ping pong issue. Which kind of goes along with some of the other owners reports of changing their rears, then having an issue.

The only remaining issue that I have is the fact that when they did the alignment, they did not set the steering wheel perfectly straight, so when I’m driving in a straight line, the wheel is turned a bit to the right. We’re talking maybe 5 degrees or so.
So I’m not sure if I should be a nag and bring it back for another alignment or not. Any opinion on that?

Thanks for the update. In most 4 wheel drive systems you want to change all 4 tires at once. But, this is because the front and drive trains are interconnected. And you don't want the front tires rotating at one speed and the rears at another speed and the differential caught in the middle. (see diagram on rotation in Should You Replace All Four Tires on Your AWD Vehicle? - Les Schwab)

But with a Tesla front and rear motors are independent. Or, perhaps they are not as far as the electronic systems for stability and speed control in AP and other systems are concerned?

 

[BullishPip]

Wow. Great post! Glad to hear you found the root cause (needed to replace the front tires).

I'd personal wait like a month or so then schedule another appointment and mention the alignment seems to be off on the highway.

GTK (replace all tires at the same time to avoid ping-pong issue)!

 

[mswlogo]

It’s a good idea to replace all tires at once for when the traction control or ABS kicks in all tires have similar behavior. But for cruising straight on a dry highway this should not happen.

Very strange problem.

Thanks for posting though.