Tires: Very poor tread life

Question
Hello Barry, I have a 1999 Toyota Solara and due to poor tread life I've replaced full sets of tires
4/2011 97000 miles
4/2012 107000 miles
8/2013 120800 miles
and now at 130000 I'm told my tread is 3/32nds and all 4 need replacing. I've replaced brakes routinely, new tie rods installed on 3/14 and my mech looked at the tires 3/14 and said they were fine, they are rotated every 6,000 miles.  I get full alignment every year.  I don't understand why this started occuring. I previously replaced tires in 2007 with Firestone.  Note:  2011-14 all with Discount Tire Michelin products.   Can you advise me?

Answer
Sandi,

Your problem is not the tires.  It's either your alignment or the kind of driving you are doing - or both.  

Based on what you've sent me, you aren't driving a lot of miles on a year.  That probably means you take fairly short trips with lots of turns - I call it "City Driving".  Most tire wear occurs in the cornering mode - and the more corners you make, and the more severely you corner, the faster the tires will wear.

There's nothing you can do about the routes you take and how many turns you make in those routes, but gentle cornering will pay dividends.

Then there is alignment.  Are the tires wearing evenly?  Are all 4 wearing out at the same time?  If not, then there is likely a problem that needs to be addressed.

First, my experience says that the published alignment specs are too wide.  Not the target value - the allowable range.  Many alignment tech think that if the alignment is in the green range it's good to goo.  Not true.  And in the case of your car, the camber can be too much and cause one sided wear and still be "in Spec".

So you need to find an alignment tech who will align the car to the target values - and especially make sure the camber is below 1 degree.

Hope this helps.