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MNBoxster · 05-25-2007, 10:44 PM

Hi,

One thing to bear in mind is that on many Tires, wear is not linear. I have found this to be especially true of Dunlops, Pirellis, and BF Goodrich.

You may have used only 5/32s for 12k mi., but the Tires may be all in by 13 or 14k mi.

I had a set of Dunlops on my Esprit a few years ago (GREAT Tires btw), anyway, they showed only 3/32s wear in 10k mi., but were at the wear bars by 12k mi.

I don't know what the Tread Gauge cost you, but here's a way to gauge tread depth that costs you nothing:

Take a Penny and insert it into several tread grooves in the tire (Lincoln facing you and going into the tread head first). If any part of Lincoln's head is not exposed by the tread, you have more than 2/32" of tread depth remaining.

Now, take the same Penny, reverse it, and insert it into several tread grooves in the tire. If the top of the Lincoln Memorial is always covered by the tread, you have at least 6/32" of tread depth remaining.

Finally, take a Quarter, and place it, Washington facing you, head first, into several tread grooves in the tire. If any part of Washington's head is not exposed, you have more than 4/32" of tread depth remaining.

Now, you can also use the same methods and with a fine line Sharpie, mark the coins prior to an event and set them aside. After the event, using the same coins, test the tread depth again and place another mark on the coin. Check the distance between marks to determine your Tire usage for the event. Hope this helps...

Happy Motoring!... Jim'99

05-25-2007, 10:44 PM	#4
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	Hi, One thing to bear in mind is that on many Tires, wear is not linear. I have found this to be especially true of Dunlops, Pirellis, and BF Goodrich. You may have used only 5/32s for 12k mi., but the Tires may be all in by 13 or 14k mi. I had a set of Dunlops on my Esprit a few years ago (GREAT Tires btw), anyway, they showed only 3/32s wear in 10k mi., but were at the wear bars by 12k mi. I don't know what the Tread Gauge cost you, but here's a way to gauge tread depth that costs you nothing: Take a Penny and insert it into several tread grooves in the tire (Lincoln facing you and going into the tread head first). If any part of Lincoln's head is not exposed by the tread, you have more than 2/32" of tread depth remaining. Now, take the same Penny, reverse it, and insert it into several tread grooves in the tire. If the top of the Lincoln Memorial is always covered by the tread, you have at least 6/32" of tread depth remaining. Finally, take a Quarter, and place it, Washington facing you, head first, into several tread grooves in the tire. If any part of Washington's head is not exposed, you have more than 4/32" of tread depth remaining. Now, you can also use the same methods and with a fine line Sharpie, mark the coins prior to an event and set them aside. After the event, using the same coins, test the tread depth again and place another mark on the coin. Check the distance between marks to determine your Tire usage for the event. Hope this helps... Happy Motoring!... Jim'99 Last edited by MNBoxster; 05-26-2007 at 12:48 AM.