04 g35 coupe A5, factory base brake package. Okay so when I got my car it had tein 2" drop springs. I live in curvy hilly east TN. I never really experienced any rubbing until going down a back road one day and took a hard turn, while riding the brakes, but not stomping the brakes. The car's front outside tire experiencing all of the load from weight transfer acted like the abs was initiating on that single wheel, or it was rubbing HARD on the frame or something? The slip light came on. There was NO rubbing evidence, so I don't think that's it. I replaced the springs with stock ones, it still does it with VDC on or off. Maybe it's just me, but the problem seems to need more speed and load and harder braking when VDC is off. It scares me when it does it. it jerks you to the outside of the curve. and bucks pretty hard. almost like the wheel locks up. The only other thing I know that may be related is that the brake pedal gains stiffness and even pushes back after first starting and backing out of garage, and rolling downhill in the driveway. I'm riding the brakes lightly, and it makes a kind of rumble in the pedal with a noise as well and the pedal pushes back. Only time it ever does it. Pedal feels fine otherwise, and this car breaks HARD when going straight. Lol anybody know what causes this for sure? Or how to fix it?

 

Take a look at the inside edge of your tires... Our cars have an aggressive camber setup that causes the tires to wear like 3x faster on the inner edges of the tires than the outer edges, so when you look at the tire from the side of the car, the tread looks fine. When you look closer though across the whole tire, you often realize that the inside edge is almost completely bald.

I've had a situation similar to what you described happen to me before in the rain while cornering on feathered tires... so it's possible that your tires are just slipping because they are worn or cracked on the inner edges.

 

Tires may be slipping... But that's kind of unexpectedly disappointing if that's what it is, and car slips that hard under that little g force. But tires are almost new z rated and no camber wear. I'm not one of those no wheel gap camber to the max guys. I like my cars to perform as good as they look.

 

Doesn't matter if you are or aren't a camber-crazy car guy..... the '03 and '04 G Coupes don't have adjustable camber on the stock control arms. You have to get aftermarket ones if you want to be able to adjust that. They are statically set from the factory in an aggressive fashion (not as visibly aggressive as those crazy DUB cars or anything though).

I know you said they were newer... but exactly how old and how many miles are on your front tires? Most people blow through a set of fronts on these cars really quickly due to the aforementioned camber issue.

It's also possible that one of your front brake calipers is partially stuck or frozen, so when you brake hard, all the braking power goes to the other side and locks up that one wheel while the other side doesn't get much braking power at all actually applied to the wheel.

 

5000 miles? Had the drop spring on and felt the need to address the chamber issues of front and rear, so widened the holes to slots, with spot welds on each end and offset washers locked on each side. Front is now fully adjustable like the rear. Additionally rear parameters were extended to achieve correct chamber with drop. (Which is not dropped any longer)

 

I've tested, and car acts the same no matter which side receives load. So I doubt it's caliper failure unless both fronts are shot. But as stated above it brakes beautifully in a straight line.

 

Do you have factory rims and factory sized tires on them?

Switching to non-factory sized tires can throw off the traction control system while cornering since it can incorrectly detect wheelspin or slippage when in fact there is none. This should only affect things related to tires rotating and not related to the VDC system reacting to things based on the yaw sensor.

 

If wheel lock up is occurring under 10 MPH Check your ABS sensor.

 

Factory wheels and tires. And it's quite a. Bit faster than 10 mph... Lol