This is going to be hard to explain... I was on long stretch of open road and decided to turn my wheel quick left, then quick right "like race cars that are warming up tires" and I noticed that rear end felt a little delayed. Almost like it was starting to oversteer and break the traction loose but it wasnt. Speed was around 35-40 MPH, Alignment is -1.6 up front, -1 rear and 0 toe. Tread is Potenza RE970AS, 40 PSI all the way around. When I had the stock alignment I never noticed it...I do the "tire warming" quite a bit. Just curious if anyone else has noticed this on their cars, or am I just weird?...lol. Thanks in advance for the input!

 

No need to warm up the tires.

When did you get your alignment last?

 

IMO. Could be a number of things.

Rear tire pressures (You noted 40 psi. Seems very high as a cold setting. Imagine what the hot readings are?), road conditions, Rear arm bushings, stock rear shocks going bad. You didnt mention having an aftermarket rear sway bar

 

Just an fyi when you see race cars scrubbing their tires, it's to get debris off and not to warm them up

 

Couple months ago. I will post my results when I get off work.

 

Stock sway bar. I inflate my tires to conserve fuel, not good I guess huh? I also hate the feel of soft tires, feels like I'm driving through sludge. Road surface is smooth, it's just a quick jerk either way and feels as if the car is not moving as one...the rear just feels delayed to straighten up.

 

Your tire pressure is too high assuming that is the cold PSI. Even if it was the warm PSI I really wouldn't go over 38PSI. Also given your tires are AS I'd imagine the sidewalls are too stiff so the sway simply could be from the sidewall flexing a little.

 

I dont think tire pressure is his issue (assuming they are all above 20psi at least)

I would pull off your rear wheels and check that all bolts are right and its not something ready to fall off. If everything visually looks good, I'd take the car back in and have the alignment checked.

 

Here is my Alignment. What do you think?

 

Well, I think it could be the pressure. Too much pressure and the contact patch get narrow, especially on the rear where less weight.

 

I will try lowering tire pressure. I just assumed that high PSI would be ok since it is recommended for auto x. I know DD is not the same but why wouldnt it be ok right?

 

Typically you will run a little higher PSI during an auto x vs the road in order to help the sidewall resist flex. But running it too high is also a bad thing. Be careful setting your tire pressure because as your tires heat up the pressure will also go up. My cold pressure of 32 went up to 39 after a run during an auto x. If you are starting at 40 imagine how high it may get after driving.

If you wanna run high pressure all the time my advice would be to have your tires filled with nitrogen. The pressure remains so much more consistent. With nitrogen in my tires I only see my pressure rising ~2psi after getting them real nice and hot.

 

Thanks for the replies. I lowered the pressure and that sway feeling disappeared.