Tread depth
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From: Tempe AZ
Tread depth
The old timer advice was when you stuck a penny in the thread and could see all of Abe's head it was time to replace the tires. Is this still accurate for GY Run Flats or how far down is safe? 
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Technically, replacement is recommended when the wear bars are even with the threads. Realistically, the closer you get to bald, the more dangerous driving is in the rain. If you never drive in the rain, you can wear them down to a "Hey, your tires are bald, mister" depth before trashing them for new ones. I got rid of my runflats at 16,000 miles, went to non-runflat GSD3s and never looked back. The difference is amazing.
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Originally Posted by az57chevy
The old timer advice was when you stuck a penny in the thread and could see all of Abe's head it was time to replace the tires. Is this still accurate for GY Run Flats or how far down is safe?
Whats that in inches?
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They say to replace tires when the tread depth is down to 2/32nds - but, when you get down to around 4/32nds things can get pretty slippery. When I had my original EMTs on the car, traction was a problem at the 4/32nds level. Not sure where that placed it on the penny scale.
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You can pick up a tread depth guage at any pepboys for about 3 bucks. Most tires should be taken off at about 2/32nds. The EMT's are pretty well shot at 10/32nds. 
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Originally Posted by girl-ina-box
omg it's dirty! This is the right rear....didn't know which tread to insert it in.
When I got rid of my runflats, there was plenty of tread on one side, and the cord was showing on the other side. Badly misaligned ... I should have checked more often!
The only thing dirty on that car is the tire tread ... can't keep that clean unless you never drive it at all.
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Originally Posted by girl-ina-box
omg it's dirty! This is the right rear....didn't know which tread to insert it in.
Great photo, "GIB". Depending upon the brand, model, and, application, most "street" tires start life with 9/32 to 11/32 of tread depth, brand new. Now, if you look closely at this specific photo of yours, you will see a raised embossed Triangle Tire Emblem. In the tire industry, these triangular tire emblems are molded onto the outside shoulder edge of a tire, and, help to allow any consumer to locate the raised, rounded horizontal rubber bars called Tread Wear Indicators. These Tread Wear Indicators are located throughout the surface of the tire, directly across from the triangular emblems, and, are generally at a height of 2/32 of tread depth. In general, you NEVER want to allow your tire to be worn so far down that you actually begin to wear down these Tread Wear Indicators. 
Last edited by edensknight; Mar 24, 2006 at 06:38 PM.
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Hi Gary 
EK---I learned something new today!!!!
Never knew what that triangle was for....to be honest, never even knew it was there!! Thank you for sharing that!!
Great forum this is!!!
Lori
EK---I learned something new today!!!!
Never knew what that triangle was for....to be honest, never even knew it was there!! Thank you for sharing that!!
Great forum this is!!!
Lori
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From: Columbia MO
Originally Posted by edensknight
Great photo, "GIB". Depending upon the brand, model, and, application, most "street" tires start life with 9/32 to 11/32 of tread depth, brand new. Now, if you look closely at this specific photo of yours, you will see a raised embossed Triangle Tire Emblem. In the tire industry, these triangular tire emblems are molded onto the outside shoulder edge of a tire, and, help to allow any consumer to locate the raised, rounded horizontal rubber bars called Tread Wear Indicators. These Tread Wear Indicators are located throuhout the surface of the tire, directly across from the triangular emblems, and, are generally at a height of 2/32 of tread depth. In general, you NEVER want to allow your tire to be worn so far down that you actually begin to wear down these Tread Wear Indicators. 
Nicely stated EK.
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From: SoCal
Originally Posted by Evil-Twin
2/32 in. or 1/16 in. or 4/64 in. or .0625 inch. which ever comes first
Uhhhhh..That would be 1/16 right ??????
............. it has a "1" in it for first.......right???????
BUMMER......my NittoR2 tires only havef 5/32 to start with
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From: Tempe AZ
Originally Posted by Evil-Twin
2/32 in. or 1/16 in. or 4/64 in. or .0625 inch. which ever comes first
Thanks All I figured the bars were there somewhere now I know where to look
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The original question was about the penny (I always heard it was a nickel but the distance may be the same on both coins). The distance from the edge of the coin to the head is 2/32 of an inch and is the same measurement as the wear bars on the tire. You put the coin in the deepest part of the tread to make the measurement. Although since the wear bars are on all tires there isn't much need to use a penny or a nickel anymore.
Bill
Bill
