max59

I have noticed lately that my GT4 is moving a bit side to side when going slow over road bumps and water puddles. This is a bit unsettling as I have never experienced this kind of movement on a car before, especially over puddles. I have around 20K km on the car and original Cup 2 tires that do not show any sign of excessive wear.
Is this movement a function of the suspension, is it supposed to be like this as I assume that GT4 suspension is a bit more advanced than other cars that I had before (M3, STI), is it a sign of a suspension component wear or is it something else?

Viperguy324

Very surprised that you got 20k Kms out of cup2s ....I bet you are sliding everywhere... lol

Seriously, I don't see any GT4 being a violent as a properly setup STi ...The DCCD I have on my N12 is pretty rough on the ribs with slicks.

paradocs98

I think I experience something similar. When going over bumps in the road at speeds of 10-20 mph, especially if there's any steering input at all, the back end seems to move around and act "nervous." Maybe it's a function of rear toe setting on the suspension? I did have an alignment just recently, though, and set the rear for slight toe-in. I would think that toe-in in the rear would increase stability and stop this nervous/wiggling feeling in the rear, but maybe over bumps the suspension geometry changes and it actually becomes more unsettled than a zero toe setting.

HenryPcar

Bump steer is normally attributed to worn suspension parts or something is loose. Check that all the tie rods and fasteners are torqued correctly.

evil panda

my bet is worn PSC2's...mine are worn to about 5/32" and during a sudden downpour i felt like i was driving a cigarette boat. needless to say, i'm not driving them in the rain again until i get replacements.

did you actually measure the tread depths, or did you just do a visual inspection? like another person said, i'm surprised you got 20k out of a set.

max59

I have about 5 mm left, so, a bit more than 5/32". I am not sure this is due to tire wear, I had tires with way less tread and never experienced anything like this.

James88

I've had this issue in heavy rain on slightly bumpy roads.
Had too much front toe, its now at factory spec, seems to be a lot better but haven't been back to those roads yet.

max59

I haven't changed anything from factory settings.

max59

I checked the tire pressure today, it was 26 psi front and 29 psi rear, that's a bit lower than what the manual recommends, could this be the problem?