can anybody tell me what´s the best tires for xterra 2002 4x4 for offroad? Gracias!

There is no such thing....every tire is a compromise, and they are all better or worse in some way.

For example, what makes a tire work great off road, tends to make it work less well ON road;

A racing slick might be best on a smooth dry road, as more rubber will be in contact with the ground, etc);

A racing slick will SUCK in mud...it will have no paddle wheels for traction in the gook.

A mud tire with deep lugged paddles to churn through the goo will SUCK on the road, as the big squirrelly tread blocks will squirm and roll over on pavement, and the large voids between the tread blocks will reduce the rubber in contact with the road, etc.

Off road, an aggressive mud tire as above might dig in, and keep bogging down in sand, but do great in the mud.

A good mud tire mud not have strong enough sidewalls to protect against rips from sharp rocks, or might have TOO stiff a sidewall, and be unable to allow the tire to wrap around a rock for traction.

Ans so forth.

We need to choose between awsome offroad vs terrible on road, or, OK on and off, or Better on sand because its beaches or dunes that you live for, etc.

So - To know what's best for YOU...you need to say what you want the tire to DO for you, and, how much ON road performance you are willing to SACRIFICE to get good off road performance in WHAT TERRAIN.

So - Where are you going to be off roading, and, what are you priorities for performance?