Question about tire plies
 

I am trying to buy tires for my 1984 300SD. I noticed cheap tires have 1 tread ply and 1 sidewall ply (not counting steel belts). The more plies the better. Which tires have 3 tread plies and 3 sidewall plies? Is there such a thing as 3 plies?

Your correct about cheaper tires having less plies. If you are wanting to economize on tires, I wouldn't get too hung up on that unless you are putting tires on a vehicle that will haul a heavy load.

Pay more attention to the specified load rating, treadwear rating and tire construction.

Load rating should be self explanatory, don't use a tire with a marginal load rating. It will probably not cause safety concerns as long as it is adequate, even barely, but the tire will be shorter lived.

The Treadwear number is stamped on all tires, and if you are economizing, it will be false economy if you pay very little for the tire but it has a low treadwear number. Since it won't last long, your cost per mile will increase.

Lastly, you should seek out a tire, regardless of price, that is made in a radially sectioned mold. To determine this, look at the mold marks. They are indicated by the rubber flashing, sort of like what oozes out of a waffle iron if you pour in too much batter. If these lines go radially toward the axis and across the tread this is what you want. This is the Michelin method and is now used by other tire manufacturers, even some that produce less expensive tires. If the flashing goes around the center circumference of the tire, it was made in an old fashioned clamshell mold in which the belt cannot be consistently placed in proper position.

Hope this helps,

There are plies, and then there are plies
 

Some radial tires have only the sidewall and the belt, the latter of which is nowadays most often two plies of steel, although four plies of rayon and even of some variety of fiberglass have been tried (and failed often in the latter case!). The sidewall will be one or two plies of rayon or some other synthetic -- it's difficult to count whether you've actually got one or two plies there in a true radial.

But there are several more important things to worry about:

If you want a real handling tire, nowadays you may find it in one which has an additional nylon or synthetic "cap ply" over the belt, running entirely circumferentially, whereas the belt consists of crossed plies. This really adds some quick steering response in many cars, although some of them show the old-fashioned nylon bias ply tire trait of thumping a bit until they warm up. On the other hand, on some of the super cheap or smooth ride oriented tires, usually SR or totally un-speed rated, the belts themselves are very narrow and don't even cover the whole tread contact patch width. Leave these to the blue hairs in the Lincoln Town Cars (alas, nowadays many of them are younger than I am!), although when one is behind me, I wish they had something better, too.

Furthermore, a factor which can add a lot to the handling performance of a good tire is the circumferential reinforcement of the sidewall just above the bead area. Some smooth ride tires have almost none, but on my Michelin 225/60 HR tires, almost half the sidewall is stiff as can be, only about two inches are truly radial. This, of course, reduces smoothness a bit, too. When you get to the really low-profile tires, they don't need this, because the rim is doing the same job in the same place.

My decision:
 

I have bought Yokohama Avid Tourings from Tirerack today. They seem to have a good load rating as well as the cap ply. Thanks for the help.