Yet another tire thread - Cougar X-Lite 26SAB

Dayle1 wrote:

bpounds wrote:


I don't buy any of that.

The E rated tire has a stronger carcass and additional belts, which makes it resist damage from road hazards, bruises, and twisting. The same construction that makes it able to resist higher internal force (air pressure), makes it able to resist external forces.

I always run my ST tires at, or just below, max rated pressure. There isn't any reason not too. They will run cooler, pull easier, and handling is not an issue with a trailer.

Since there is no such thing as a free lunch, everything you say about the stiffer tire and IT'S ability to resist road issues does mean more force is transmitted to the fiver suspension, frame and body. There is a reason why tires are not solid and having a tire stiffer than needed comes at a price.

No desire to argue over it, just for discussion, what you say is logical. Stiffer tires will obviously transmit more vibrations to the trailer. I tend to think that, in a 225/70-15, the difference between a D and an E felt in the trailer, cannot be enough to make any difference.

And since we know that ST tires don't have a good success rate when run right at their load limit, I would not run them without a generous safety margin. That safety margin is what bumping up to an LR-E gets you.

Continuing the logic, if we consider 16" tires, what you say about stiffer tires transmitting more vibration has to be true as well. We all know how much more a like sized LT weighs compared to an ST, and how much stiffer the sidewalls are. The guys pulling heavy trailers know that the stiffer LT is worth it, regardless of cost or vibration.

There is a lot of conflicting information out there regarding running an ST at full pressure, or per a weight/pressure chart. I come down on the full pressure side, although I usually go about 5psi below sidewall max, just because it feels good to stay away from hard limits.