I recently put on a set of Falken Torque 5's with Toyo Proxes 4 tires. Since then my limited slip has come on mostly on the highway. I'm not going any faster than 70 and most of the time it's on a straight away. My slip keeps coming on and causing a lot of problems. I'm trying to avoid the $90 diagnostic fee at the dealership at all possible. The car won't accelerate and is going to get me rear-ended if it keeps up. Anybody got an idea what the problem might be? I did just recently add some higher performance break pads to cut down on break dust. The car only has 28k miles on it and I've owned it for 3 and 1/2 years.

 

What are your front and rear tire sizes?

 

235 35 19w. I actually took them off during the winter and it didn't start until I put them back on.

 

You've got 235/35/19 on all four wheels? If so, that likely your problem. The OEM tires sizes are staggered, the rear tires are taller than the fronts. On some cars, when you have no stagger, the VDC or TCS system will kick in and that illuminates the Slip light for a second or two as it cuts engine power.

If you've driven on this configuration before and not had any problems until now - two other possibilities are 1) you damaged a wheel speed sensor when changing the brake pads or 2) you damaged a wheel speed sensor when mounting the wheels back on the car.

 

What do you suggest I do to fix this. I want to keep the wheels on. No, they're not staggered. Before when I had them on, they handled much better than the factory ones.

 

Additional Information
Location:
Richmond, VA

It would be helpful if I knew what you drove? Do you have VDC?

 

04 350z Enthusiast. It's automatic. Yeah Yeah Yeah. I know. I should have gotten manual.

 

You have a difficult problem to solve. 90-percent of members with TCS have no problems with the same size tires all around.
I assume that you put the new tires on the rear axle?
What happens when you take a ride with TCS OFF?

 

Just for grins, try swapping the front and rear wheels.

 

They are all the original tires from when I had the wheels on last year. Nothing crazy happens when I take the slip off. Unless I try a hair-pin turn going 60. I haven't got up the guts to see what would happen on the highway on the same situations when it comes on and I turn it off.

 

this happened to me a while back, but that was cuz i was running 35's in the front and 30s in the rear, I don't think that's the problem here, so I don't really know the solution to your problem ...

 

If you're getting into limp mode, then it's something more than just a missmatch of tire size.

 

i notice this too on same sized tires but i always turn tcs off at the track and rarely drive the Z hard on the hwy. btw, where is the wheel speed sensor?

 

Follow the electrical cable going to each wheel knuckle.