Hope someone can shed some light on this issue.
I recently replaced my rear tires with toyo proxes 4 (size: 245/45ZR18) and kept the front tires the same (BFGoodrich g-Force T/A) (size:225/45ZR18). The fronts still have a few thousand miles to go. The wheels are Stock Rays that came with the Track model.
But, now the car is acting up at high speeds. Kind of hard to explain but it's hard to control on the freeway and it's very sensitive moving side to side. Another issue is that while turning the SLIP light comes on (sometimes) and the VDC starts applying breaks.
The new tires were balanced and the tire pressure is correct. Also, checked the lugs and they were on tight. Only thing I noticed was that one tire was made in Japan and the other in the U.S. But, both are the same model and size. The tire people said that shouldn't cuz any problems though. I wonder if I have a defective tire or something.
Thanks for your help in advance.

 

Tire size is not the problem. Its perfect for VDC.

 

thats a strange problem, have you been able to try on a different set of rear wheels from someone elses car to see if its the toyos giving you the problem?

 

No, I haven't tried that. I had other set of tires on there previously and they never gave me any issues. But, they were the same brand as the fronts.
Heck, even with the spare on the rear I wasn't getting any traction problems.

 

BTW, the VDC does not apply the brakes. Does it do the same thing when you turn the VDC off?

 

I haven't tried turning it off. The SLIP light only came on twice so far both when I was turning on an off/on ramp to the freeway. I just dropped the car off at the tire place. They're going to test drive it and call toyo for directions. I doubt they could duplicate the traction issue though =(
I have a feeling they want me to replace the fronts with the same brand tires (which I don't want to do). He was saying I am getting more traction in the rears since they're new tires. I didn't think that made sense.

 

you have to sets of tires with very different levels of grip. Clearly that is your problem. I guarantee if you put matching tires up front that the VDC issue will go away

 

that's what I was afraid of ..

 

did you drive the new tires for a couple hundred miles before re-evaluating them? need to break in the tires and allow the mold release chemicals to evaporate off.

 

No, I only had them on for a week. The car just doesn't feel right. I am all over the place. Things started to get scary around 100mph.

 

i have toyo proxes 4 and have no traction with those tires. If i were you, replace those tires and get something else. Another friend of mine who has a honda s2000 with the same tires and he complains about the traction issues.

 

Great .. wish I knew that before. They wanna put Proxes 4's on the fronts now. He said he talk to everyone (toyo tech rep. and other ppl) and everyone recommended doing so. They keep pushing those tires one me. I am out another $350 now.

 

I don't think they Proxy 4 is a good tire either. I think Toyos street tire line sucks, although I like their RA1 and R888s. Guess I'm spoiled by PS2s.

What is going on at 100mph? What is the air pressure in the rear? Something else isn't right if the car can't go straight without an issue. Lousy grip in the rear in a turn would cause oversteer, and kick the VDC, so that I get. But going straight you have an issue?

 

Well, not sure how to explain it but the car is pulling from side to side going straight and just not stable at high speeds and getting bad traction.

I ended up telling them to take the Proxes 4s off based on the replies here. The problem is that they only had a couple of other choices. Apparently, my current fronts BFG g-Force are supposedly discontinued (only T/A KDW 2 are available but not in stock). That leaves me with Coopers which I am not familiar with and Goodyear Eagle GTs. I wanted the GT's but they wanted almost $200 each for them and wouldn't price match Tirerack ($143). I hate getting ripped off more so I opted for the cheaper Coopers on the rears for now. We'll see what happens.

 

have the Toyo T1R's on my stock 06 wheels and love them and haven't had any problems with them...then again I have all 4 same tires. try get some proxy 4's for the front and that should solve the problem.

 

Haha wow i just had the same problem i was going over 100 the other day and if started acting up idk i guess i wont go over 100 anymore lol till i get new tires i have alot of thread life left blahhhhhhh!!!!

 

good to know I am not the only one
I had them put the Coopers on rears. It didn't totally fix the problem but def. not as bad on the freeway. The slip light still comes on when turning fast. problem should go away w/ two more crappy coopers on fronts haha.
Thanks for all there replies.