I've just begun uncharted in its hardest difficulty, and well, it's f***in hard! I'd like to know who beat the game in this difficulty, if they have any "anecdote", ... I personnaly think that it's one of the most difficult trophy to get. So?

I found it tricky on normal.... you sir, are a brave man!! (though I might try it on hard, but never crushing)

Crushing is ridiculous. It will make you cry. Have fun!

Hard is ... well hard but I got through in, just have to learn when to stay down....and having already played through it onc on normal having weapon select helps. :P

Never tried it on Crushing though...

Shotgun ftw ;)
Been there, done it, got the trophy

Start to learn to shoot without aiming and it won't be so hard ( your characted can shoot from cover without showing much of himself if you don't hit the aim button to shoot, if you use shotgun with that you can kill guys coming at you while staying relatively safe). It works well with the gun too, just takes a lot of shots and harder to aim..

Crushing is not that hard, sure you will die a lot at the end. For me it seems crushing became even harder after the patch, i guess it's just me.

 ^this is the best advice.  Crushing was the best.

Always try to carry the shotgun or the Wes.  There are a couple of levels where you will die a lot.  Learn to throw your controller at a couch or bed.  Once you enter the level you can usually fall back a little and let the enemies spawn and approach you.  As long as you can shoot these guys without aiming you will be fine.  I view it as them bringing me more amo.  Usually the guys that approach you have the high powered weapons.

Learn to use your weapons without aiming while being stuck to cover.  I almost never aim with the shotgun.  Just run towards the enemy and shoot or position your body while stuck to cover.  Also, some times it is better to hide behind an object but not actually stick to cover.  In some situations it will allow you a better aim. 

Learn where the enemies spawn in a level and the order in which they spawn.  It is not random.  A lot of people have a problem with the Cistern level in Chapter 5.  It is a pretty easy level once you understand the spawn order.

Whoa guys thanks for all the advice but I'm fine lol ^^ I'm just after the spot where the plane has crashed and I managed to do it

In fact, it's the first time that I play a game in crushing mode, and I have to say I kinda like it!

I never found crushing to be all that hard and I never used grenades or shotguns. Remember that good cover and the pistol are your best friends.

This was the only reason I kept my sanity: 

When you get to the water area, run back out into the sunlight and the guys will spawn... then just pick them off from above!