Just bought 2003 Viper with 17,000 miles. Tires are Michelin Pilot Sport ZR 345/19 on rear and 275/18 on front. I was told car came with run flats ZP tires. Am I lucky since these seem NOT to be run flats?? Are these a decent quality tire ??? John
Congrats on becoming Viper-ized. All 4 tires the same brand and model ???
Important:
"ZR" does not define a PS2. ZR is the speed rating of both RunFlats and of PS-2.
A RUN FLAT will have
both ZR and ZP on the sidewalls ,
and will have
direction-of-rotation arrows on them, like this >> or << Size on sidewalls: 275/35ZR18
and 345/30ZR19
PS-2 tires will
NOT have ZP, and will
NOT have Arrows, but will say "OUTSIDE" on the outer sidewall.
PS-2 are light-years better and safer than old, hard, Used Runflats.
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Trivia: There were some Pilot Sport PS tires, NOT ZP, and NOT PS2. Some called them PS-1, but there was no such nomenclature from Michelin. PS WILL have the DIRECTIONAL <<ARROWS>>, and are likley to be older / hard. Check 4 date codes on the 4 sidewalls.
It can be dangerous to mix Runflats with Non Runflat Tires
It can be dangerous to mix symmetrical with asymmetrical Tires
It can be dangerous to mix directional with non-directional tires.
PS2 mixed with PS would break all 3 rules !!!!!!
[Hint: Now IF you had NEW RunFlats, properly stored, never inflated, they would be perfectly fine for 5-6 years in storage! Still available, they were a great tire only when NEW, but they deteriorated quickly after heat cycles of 3 yrs of DRIVING = RunCraps] When new, the PS-ZP tire set the OE record for lateral skidpad Gs. Tremendous OEM grip when
new.
