If you're finding the 18-135 is blurry, I believe it is definitely you, not the lens. This lens is discontinued but it was the optical basis of the newer 18-105 VR in use today.
The 18-135 might be the sharpest kit lens Nikon has every created. It's as if Nikon told the engineers, design a lens for around $300 where you spend the effort on sharpness at the expense of any other attribute like distortion or CAs.
My gal would not let me replace hers for any other lens bar none. It's sharp, has punch and very contrasty. I've tried to upgrade her several times.
I think you must have a technique issue. You might be using a shutter speed too slow. Try to stay around 250th of a second or faster when it is set at telephoto.
You also need to make sure you're holding your camera correctly to oppose blur. The right hand should be on the right side with your finder on the shutter. The left hand goes under the lens to cup the lens. The heal of that left hand can rest on the bottom of the camera body with your fingers cupping the lens. You work the zoom with that hand underneath.
Tuck both elbows into your body snugly. Press your eye somewhat firmly against the eyepiece. You eye/neck and two arms with elbows form a complete tripod. You can also lean against a pole or wall. This technique can work as effectively as VR if you learn it well and get into the habit of not holding the camera with your arms poking out. Look at my avatar here on the forum. I was taught this in 1959 by a real pro. I was only eight.
Pay attention to good hand holding technique and shutter speeds so you will see your keepers go well up with this and all your other lenses. Your 18-135 might become your favorite lens.
As an added benefit, notice how close your 18-135 focuses. It almost feels like a macro lens. It's not but it does focus surprisingly close. You might never need a macro lens. As sharp as it is and as close focusing, this baby is a winner.
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Cheers, Craig
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