US 2001-2003 OEM Prius tire: Bridgestone Potenza RE92 XL (Extra Load) P175/65 R14
84S Treadwear 160 Temperature A Traction A
50psi max. cold pressure
US/Canada 2004-? OEM Prius tire: Goodyear Integrity (Standard Load) P185/65 R15
86S Treadwear 460 Traction A Temperature B
44psi max. cold pressure
note the low 160 treadwear rating on the 2001-2003 "Classic" Prius tires. Although Bridgestone warrantees them for 40,000 miles, most owners seem to get about 20,000 miles out of them, some up to 40,000 miles, some as low as 5,000 miles. So, your 20,000 miles on a set is about average.
First thing to remember is to keep an eye on tire pressure. Toyota recommends 35psi front, 33psi rear. However, many Classic owners have experienced rapid edge wear, leading them to up their tire pressure. Anything up to the max cold pressure on the sidewall is fine, but the common choice seems to be around 42/40 or 40/38 or thereabouts.
Remember to keep the +2psi bias on the front tires. I tried going to
40psi all around once on my 2001 Prius - any time I had to do a panic stop (my commute had lots of Dunkin Donuts shops on the way - uncaffinated people suddenly stopping for coffee without signaling and such - grr!) and any time I panic stopped the car felt like it wanted to fishtail (back come around the front). I changed to 40psi rear,
38psi front, and the car just stuck and held in place when doing the same stop. personally, I like a +2.5 to +3psi bias in the front for stopping characteristics.
Also, what type of roads are you driving on?
Do you often turn your tires when your car is not moving (scrubbing the tires on the pavement)?
How quickly to you take turns? (I find myself taking turns far too quickly in my Prius, as I don't really notice the speed...)
Have you had your alignment checked? If you're getting the average
20,000 miles on the OEM tires, then it's probably OK, but if you're getting far less than that it's usually the alignment...
All can lead to higher tire wear.
There are alternate tires out there that you can investigate, which have a higher treadwear rating (longer life). Your Toyota dealer will only tell you about the OEM tires, but as long as you keep the same load rating or better than the OEM tires, you should be fine. For some suggestions, see:
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BTW: you'll find far more Prius owners over at:
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for the 2004+ Prius:
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