C4S Tire Question - Different front and rear
#1
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Hi there,
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
#2
Burning Brakes
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Yes, it is important to keep the same tread pattern on all 4 for proper performance. I have read this many times on many forums and by car manufacturers like Goodyear and Michelin. I can't comment on the C4S mechanical issues but it makes sense.
#3
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The reason why you ideally want to keep the tread pattern from one model of tires is that the front and rears were designed to work together, which arguably is a bigger issue with Porsches than "normal" cars given the weight distribution and nuances of 911 handling. There is no hard rule that you can't use different tire brands or makes but you need to be aware that it is not optimal. A few people have done this and report that there were negative effects. If you don't drive too aggressively then it SHOULD be OK but just remember that it wasn't designed that way.
#4
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Hi there,
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
have fun
#5
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FWIW - I have had diff Michellin Pilot Sport tire tread patterns front/rear for two years now and have had no issues whatsoever. This includes drivng in the rain in a spirited manner..
#6
Drifting
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Hi there,
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
I recently had to change my rear tires as they were gone. They used to be the Bridgestone S-03 front and rear, but the S-03s are no longer available. The shop replaced the rears with S-02s, which was fine, but then they called and indicated that they needed to replace the fronts as well since the front/rear had to have the same tread pattern. It turns out that the S-02 and S-03 had different tread patterns.
The shop indicated that this had to be done only because this was a C4 due to the viscous coupling link between front and rear. Anyone heard of this before?
Thanks
Nick
The requirement of similar (<5% IIRC) F/R rolling radius for C4 & C4S is real. But if you're using the original sized tires you should be OK.
I know this topic has been beaten to death before, so some searching here can net you more inputs quickly.
#7
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Yes, the <5% IIRC F/R rolling radius for C4 & C4S is real.. The tire vendor should have the specs to ensure you will be OK. For the Michelins PS tires I have with diff tread pattern, they are within tolerance.. You can tell if they are not because if > ~ 5% IIRC F/R rolling radius the ABS will not funtion.
Easy to check in a wet parking lot at slow speed by hiting the brakes hard ... I "accidentally" checked mine last year when someone didn't look while backing out of a parking space (after a rain) and I had to jam my brakes on to stop from hitting them.
Easy to check in a wet parking lot at slow speed by hiting the brakes hard ... I "accidentally" checked mine last year when someone didn't look while backing out of a parking space (after a rain) and I had to jam my brakes on to stop from hitting them.
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