Best tire with the highest ply for Prius C?

I saw your other thread about fuel economy where you mentioned delivering mail but you didn't mention poor roads in that post. You should go back and state that for maybe better answers.

Sorry, I don't have an answer to your tire question.

 

OK, here's an answer if it were me: I'd go for higher profile (taller sidewall) to both better absorb bumps/thumps and raise the car; mileage be damned.

 

Snow tires will have better performance on dirt roads than touring tires. Consider

Michelin X-Ice Xi3

It is a low rolling resistance tire so should not impact MPG more than any new tire does.

 

I don't have a specific recommendation, but I've had good luck with kevlar-belted tires.

 

The IceXi3 has two steel belts.

this is a 'better' tire but as you look at the tread it is aimed at pavement. I showed the 'ice' tires for a tread that would not get stuck on dirt.

Yokohama AVID Ascend (T-Speed Rated)

It also has two steel belts

 

That's more of a truck/SUV thing.
I don't think they make anything except 2-ply belted in small car sizes anymore.

This might be a tough decision as one with low rolling resistance (best mileage) might NOT be the strongest one.

 

Snow tires are good if you drive in an area which gets cold even if you're not driving on snow. They may wear more quickly though. Rule of thumb is temperatures consistently below 40 degrees snows are good.

As far as taller sidewalls. If you go down in wheel diameter you can go up in sidewall height. I believe the Prius C3 has 15" wheels, so you can go down to a 14" wheel and get another ~inch of sidewall (1/2" per radius) out of the change. If you already have 14" wheels then you don't really have wiggle room for a smaller diameter wheel as smaller than that and you may start impacting the brakes/suspension parts.

You can probably still go a littler wider on your sidewall on your current wheels, however as the outer diameter of the wheel goes up it will start affecting the accuracy of the speedometer and mileage calculations. Those are calibrated to a specific wheel outer diameter.

Tirerack has 14x6 alloy wheels starting around $80/ea. Alternately you could drop to a steel wheel for $45/ea. On those a 175/70R14 would keep your outer diameter the same. You could also go to a 185/70R14 with only very minor changes in the outer diameter.... you might be off by 1-3 mph.

 

In recent years, I've concluded that the greatest safety factor in winter driving is traction on ice. Traction in snow is not hard to achieve with any reasonably open tread, but for ice, an optimum combination of tread-pattern and tire chemistry come together for an additional margin of safety when icy conditions appear, and they can appear virtually anywhere unexpectedly.

I was driving up the QE2 highway in the winter of 1987 (then called the No. 2) when I chanced to look across the median, and saw a Toyota pickup similar to mine on it's side, reflected in the moonlight. Before I could give it much thought, I looked ahead and saw that I wasn't pointed straight ahead anymore. Traveling at 70 mph at night and losing directional stability is very disquieting to say the least. Thankfully, the icy patch was very short, and it gradually faded out, just so that I could regain control as traction gradually returned. My theory is that it was a micro-burst of freezing rain that happened to hit a small patch of highway.

 

You'd really want to check brake clearance before embarking on a diameter reduction. I'd just go with an XL rated tire in stock size, if available, next time I needed new rubber, and other than that take my chances. Nothing's going to be impervious to punctures, ultimately.

 

The Yokohamas I showed features great treadwear, a 800 rating.

 

Kevlar is the 'bullet proof' part of bullet proof vests, Kevlar is a lightweight alternative to steel in tires.

Kevlar - Wikipedia, the free encyclopedia

Kevlar is used in large off road tires where more steel would weigh quite a lot.

Goodyear Wrangler All-Terrain Adventure with Kevlar

I can not find any passenger car tires with Kevlar, Kelly Tires used to use it.
The Kelly Springfield Tire Company - Wikipedia, the free encyclopedia

 

I would not recommend a winter tire for such use. During higher temperature days you will chew up the soft compound and ruin the tires rather quickly, defeating the entire purpose you are trying to achieve.

You don't have any XL rated options in your size so that's out. I would suggest finding an H-rated tire because it will li,ely be the most robust option with more or thicker cap plies to handle higher speeds. Then look for a tire with a high UTQG and tread wear warranty. This will usually mean it's as harder compound and less likely to be worn down on gravel roads quickly. Sharp gravel tends to dig into tire rubber easily and get wedged into tread gaps causing deeper wear.

You may be able to use a 185/65/15 as it is only .5" taller than your stock tire. It's the OE size for the Gen 2 Prius and there are a lot of tire options. I can't say for certain if it will clear everything but I'm sure someone has tried.