Some tires have softer sidewalls than others........which may be part of the issue.

 

Load rating may be softer.

Your tires also have more squishy tread.

It'll feel a bit softer.

 

What kind of tires are they?

 

I got some new tires about a month ago and ever since then the car has felt a little floaty on the highway. It tracks fine, but if I turn kind of suddenly left or right it feels like the front turns and the rear is slow to catch up, or that it kind of floats out a little.

Have you tried increasing the pressure in the rears by 2 pounds? You'd be surprised how it helps the rear keep up (or at least feel like it does).

 

Skurvy - the roads around here are shocking with the studded tire groves. I have noticed different tire/wheel and car combos have responded to these ruts differently. Generally my r has been pretty good though. Are you noticing this on any new road surfaces? A lot of the freeway ramps/interchages north of PDX on the 205 are brand spanking new - maybe see if it handles the same there?

 

The old ones were Sunny SN3630 and were 95W XL rated, I currently have Toyo Proxes 4's. I am pretty sure they are rated exactly the same but I will double check when I get home. The difference is pretty big though and it almost feels unsafe. It almost feels like tires do when they are under inflated, but it is just the rears, and I have tried various tire pressures from 35-40.



I seem to notice it anywhere when I am going 50+. I am going to be driving up to Seattle this weekend though so I will test on some new pavement at some point.

 

Wow, I love it when you guys 'talk technical'. "Floaty, squishy"!

Regards

 

It's probably your sidewalls. If they're soft it can feel that way. But also worn tires "grab" or respond better to turning. So if you went from some worn ones to softer treaded tires you'll notice a difference. Also have you driven on them for 500 miles? That's the normal break in period for a lot if tires. All the chemicals they use in the molding process are usually off by then.

 

+1

The sidewall rigidity is a very big contributor to the handling feel.

 

Almost certainly softer sidewalls. My winter tires on 17" wheels feel like this when compared to my summer tires on 18" wheels.

 

Part of that is the taller sidewall on the 17's.

 

Have you gotten an alignment lately?

 

try all the tires at 38 psi and see how it feels

 

http://forums.swedespeed.com/showthread.php?141932-Side-Hop-and-other-tracking-issues-FIXED

Read that and tell me if that's what you're feeling, I never had violent side-hop, but I did have that "rear is steering me" feeling, and the car felt less confident, and yes, "floaty". I remember putting on BETTER tires (Kumho Ecstas from BFG GeForce all seasons) made it much worse.

 

Yup. I had performance tires on for 3 days and I felt like I had no control of the car. Some comfy DWS changed that.

 

The Toyo Proxes 4 are directional tires. Are you sure that you have them on the right way?

 

I got some new tires about a month ago and ever since then the car has felt a little floaty on the highway. It tracks fine, but if I turn kind of suddenly left or right it feels like the front turns and the rear is slow to catch up, or that it kind of floats out a little.

Ok so my car is fine and stiff in Advanced until ~70mph. Then I get the same symptoms as you. Takes the rear end just a millisecond to catch up. It feels as if I'm towing something heavy and once the rear does catch up, the rear swings just a little to the other side and then straightens out. I'm still thinking the tire sidewalls but what can I check to make sure? I pressed down on each corner of the car and the struts/shocks are fine. I'm sort of starting to worry.

 

Could be the 4C too. Anyone near you that you could switch rear wheels with for a little driving test?

 

It's not the usual rubbing noise you're hearing?