Mustang210

Hi Everyone,
I was looking for help with my 2015 mustang GT My car has less than 7k miles I bought it with 6k miles on it. The issue is after my car has been sitting a few days in the garage. When I drive it out and turn out of the driveway onto the street, The front passenger tire feels like it is flat. It thumps thump thump and slips almost like I hit some black Ice. This happens for just a few feet during the turn Then it goes away. I can drive it the rest of the day with stops and starts and it will not do it again. Just the first turn of the day out of the driveway. I have tried turning sharply both left and right and at different speeds while driving but it will not do it again and feels solid. I took it in to Les Schwab for a tire rotation hopping this might fix it, and asked them to look for any issues after I explained what was going on. They did not see anything and of Corse driving it down to them it "warmed" up and it will not do it again to show them. The car would have to sit in their parking lot for a day or two in order to show them. Even after the rotation the car still will do this. Any ideas? This is very frustrating. Someone said it might be an air bubble in the power steering? They suggested to remove the power steering cap and slowly turn the wheels all the way left and right a few times to try and work out any bubbles. ? ? ?
Thanks in advance for any suggestions.

SpectreH

It isn't bubbles in the power steering since the Mustang has an electronic unit, not hydraulic like they once had.

Mustang210

OK. Thanks. I did not think so... any other ideas?

SpectreH

None at this time. If was stored for months, I'd say tires flat-spotted from being parked so long. Doesn't make sense that it happens in a couple of days.

Bert

hmmmm . . . . just some SWAG's . . .

is it cold where you are now (about 45 degrees or less) and do you have summer-only tires? if so, it might be a flat spot on the tire, that quickly goes away as you drive a little and the tire warms up a little

check for any play in the from suspension (control arms, ball joints, ...) -- the usual jack-and-shake test should be good enough, like they do in annual safety inspection here in Massachusetts

Mustang210

I believe they checked that at Les Schwab. But I will do it myself this weekend. thanks for the tip. I do have summer tires on. and it is cold here. but I do keep it in an attached garage so it stays fairly warm...
I have not done anything to the suspension. No lowing kits and no accidents or curb hits etc. Also, there is no steering wheel shake or pulling of the alignment. Once it stops thumping.( about 3 to 4 wheel rotations. it feels like new again...

shaneyusa

I would suspect an issue with the tires as well. If the car is sitting very long and they are cold summer tires it can make a flat spot. I store mine so I have not noticed it, but I also put extra air in (2-3) lbs to help keep a flat spot from forming while stored over the winter.

What brand and size of tires are you running?

Mustang210

They are Pirelli 265/35/Z20 I believe they are original 2015. Les Schwab said he di see some small cracking in the tread. He said it was not bad, but would probably change them soon.