[kindofblue]

Hi all,
At 30k mi., the tread depth on our OEM Goodyear Assurance tires is 5-6mm. The treat depth on the same tire new is 10mm. With the anticipated El Nino rains here in CA, I'm wondering whether I should get a new pair of tires for the front wheels. I already have a new oem tire on a spare wheel that we carry in case of a flat while traveling so I'm wondering if it's worth it to get a 2nd new tire for this upcoming rainy season. Your thoughts?

 

[trm2]

The tires will be legally bald at just over 1.5mm. You should have plenty of tread to make it safely through rain, but it you are experiencing trouble or would just feel better with new tires, buy them.

 

[llninja]

This is an older video, but still valid.

http://www.tirerack.com/videos/index.jsp?video=5&tab=Tires

The stopping distance on water is so dramatic that I don't mess around and buy new tires far in advance of them wearing out. Anyone who holds out to try to squeeze a few months more of driving on old tires are just taking too much risk in my book. A new set of tires is about $500 installed. Trying to get that last $100 worth of miles out of your tires just isn't worth it compared to compromising the safety of family. Although I've been called the ultimate cheapskate in the past, tires isn't one place where I cheap out.w

 

[trm2]

This is an older video, but still valid.

http://www.tirerack.com/videos/index.jsp?video=5&tab=Tires

The stopping distance on water is so dramatic that I don't mess around and buy new tires far in advance of them wearing out. Anyone who holds out to try to squeeze a few months more of driving on old tires are just taking too much risk in my book. A new set of tires is about $500 installed. Trying to get that last $100 worth of miles out of your tires just isn't worth it compared to compromising the safety of family. Although I've been called the ultimate cheapskate in the past, tires isn't one place where I cheap out.w

Thanks for linking to that video, eye opening! So TireRack recommends replacing at 4/32 inch (3.2mm). OP seems good to go.

PS am I the only one who is bothered by tire tread being measured like it is? I mean 4/32 should just be written as 1/8!

 

[llninja]

Thanks for linking to that video, eye opening! So TireRack recommends replacing at 4/32 inch (3.2mm). OP seems good to go.

PS am I the only one who is bothered by tire tread being measured like it is? I mean 4/32 should just be written as 1/4!

But if you watch the video, the car at 4mm stops about 100 ft further than new tires. And the heavier truck stops hundreds of feet turn her on wet pavement. So my conclusion is the heavier volt should get new tires far in advance of the wear bars, so depending upon your aversion to risk, maybe 5-6mm is the time to get new tires. It's all up to you.

Tire tread is always measured in 32nds of an inch. If you always simplified then you force people to do math in their heads when comparing 3/32 to 1/8 (not 1/4 as you wrote) to 5/32 to 3/16.

 

[trm2]

But if you watch the video, the car at 4mm stops about 100 ft further than new tires. And the heavier truck stops hundreds of feet turn her on wet pavement. So my conclusion is the heavier volt should get new tires far in advance of the wear bars, so depending oupn your aversion to risk, maybe 5-6mm is the time to get new tires. It's all up to you.

Tire tread is always measured in 32nds of an inch. If you always simplified then you force people to do math in their heads when comparing 3/32 to 1/8 (not 1/4 as you wrote) to 5/32 to 3/16.

Oops, shouldn't have posted before coffee. Corrected my fraction.

 

[kindofblue]

Hi all,
First, thanks for your comments and perspectives. I've contacted Discount Tire about getting a 2nd new tire (1st is on my spare tire/wheel) and in the automatic ordering process they recommend the new 2 tires go on the rear. I was thinking the front as the Volt's a front wheel drive and the added depth up front would be more useful in the snow. What say you?

 

[canehdian]

Hi all,
First, thanks for your comments and perspectives. I've contacted Discount Tire about getting a 2nd new tire (1st is on my spare tire/wheel) and in the automatic ordering process they recommend the new 2 tires go on the rear. I was thinking the front as the Volt's a front wheel drive and the added depth up front would be more useful in the snow. What say you?

You should replace all 4, if any.
If you really only want two, those with the best tread should go on the rear.
Your goal is improving stopping, not wheel traction to accelerate.
Having the better tread on the back ensures stability when braking.
If the rear slips before the front, you'll start a spin.

Always have the better set on the back.

 

[Barry]

While it is good advice to put the better tread on the rear, I can tell you that will not give you the protection from hydroplaning that you are after.

Personally I would drive on the current tires longer and then replace all 4 at once. Possibly buying 3 and using the spare if you like the brand/model of the spare. But I would not use it if it is an OEM Goodyear. There are much better choices.

I agree with the above statement about not being frugal on tires. If you can afford to buy a Volt, you can afford a matching set of tires.

 

[bentbiker]

Reid,
How are you measuring tread depth? You are giving numbers in millimeters when tread depths are normally reported in 32nds of an inch. You say the tread depth on a new OEM tire is 10mm (12.6/32 "); actually, TireRack reports that the tread depth when new is only 9/32". If you use 5.5mm (midpoint of the range you give) that is almost 7/32", and very close to new. If you want to buy new tires, you can certainly do so, but there's nothing wrong with your current tires.