Does anyone know what it can actually be?
car is >100 000 miles.
I asked couple of people and everybody told me that it's almost impossible for the strut to go ban on this car.

if not strut then what is it?
(When car hits the pothole I can hear the clunk sound)
When I heard the same sound on my maxima (a year ago, I had to change both front struts)

If it is struts, does anyone have any instructions on how to change them?

Struts do wear out. Anything made by man can wear out. Push the front corners down, one at a time, observe for rebound. If present, struts are shot. However, clunking noises are more characteristic of ball joints or bad wheel bearings.

------------------
Jeff L
1987 300e
1989 300e
1987 BMW 325

I'm sorry if I described the sound wrong,
it sounds like the strut sound.
Can somebody add any more details how to change the strut in this model?

You'll need a spring compressor. Raise front of car. Put it on stands, have a method of jacking the front suspension after the car is up. Remove wheel, partially compress front suspension. Compress the spring, remove retainer nut and shroud from the top of the piston (under the hood). Unbolt the bottom of the strut from the wheel hub carrier. Remove the strut, pretty much reverse of removal to reinstall.

------------------
Jeff L
1987 300e
1989 300e
1987 BMW 325