Tire Tread Depth

[HowAboutThis]

Just got oil and drive belt replaced at dealer. The multipoint inspection showed 6/32 and 7/32 on tires. Which was odd, because I have a manual depth gauge and was getting 8-8.5/32nds last week and when rotated at Discount Tire last week they told me 8/32nds. They use those weird digital laser things, but it seemed to match my cheap, manual one. Anyway, I brought it up to the service advisor and he took this small, digital gauge and said that's that they used and it showed 7 and 6 on it.

I'm wondering if theirs was set to millimeters instead of inches? What else could be going on?

Just found it interesting.

 

[DougR]

It appears they reported thread depth at a wear bar. Wear bars are about 2/32 inches. I suspect they measured the depth the same way you did and then subtracted 2/32 inches to arrive at a depth when tire replacement is recommended.

 

[HowAboutThis]

It appears they reported thread depth at a wear bar. Wear bars are about 2/32 inches. I suspect they measured the depth the same way you did and then subtracted 2/32 inches to arrive at a depth when tire replacement is recommended.

I doubt they did math. He showed me on the tire when I questioned it. It was off. He said they recently got the gauges as a dealer and used to use the manual ones. I'm thinking they're all in millimeters instead of inches. Regardless, I'll continue checking my own tread depth

 

[bullwinkle]

Dealer="tread" carefully...