I noticed that in actual photographs of M706 armored cars, some of them indicate a groove in the center of the tread while others do not. What is the story?

Molded by different companies?

KL

Unfortunately, this isn't going to be a quick answer...

I did a bit of research on this subject and could not find any info on there being different M706 "Commando Special" tire variations. There only appears to have been one type of the "Commando Special" tire (see below). Obviously there are other tire types used on the M706/V100/V150 series, but the question in this thread doesn't refer to those other tire types.

But still, there are many photos out there that show pics of "Commando Special" tires with and without the center "groove". So what gives????

MY conclusion and MY opinion is that the tires are exactly the same when manufactured; the groove is initially molded into all of them. However, once the tires are used and get some wear and tear on them, the center groove disappears.

First,I base my conclusion on the fact that pics showing "grooved" tires invariably look like newer tires and pics showing "non-grooved" tires look to be older tires.

A second factor pointing me to this conclusion is that the center groove looks to be fairly shallow and its location is on the part of the tires directly contacting the road the most; making it very possible for them wearing down quickly.

Now of course I could be wrong about this info and conclusion. But this is my ed-u-ma-cated guess as I've not found anything else to explain the groove/no-groove question; specifically info showing the presence of multiple types of the "Commando Special" tire.

If anyone has any other info on this matter, one way or the other, please let us know.