My 2 cents worth...  What shop did you take the car to?  Did you see
the strut leaking before you took it to the shop?  One of the oldest
scams in the book is to quirt a bit of oil on the strut, get the
customer, tell them their struts are leaking and then recommend
replacement of all 4.  If the car is only 3 years old, is it under
warranty?  If it were me, I'd clean the strut, drive for a week or so
and then look to see if there's any new oil visible.  If you don't
notice any bouncing or uneven tire wear, I'd be really suspicious.

HTH

That is 'awful' early for a strut to blow out.

I would be checking the warranty status.

Does the oil look fresh or is there a built up layer of dirt and grunge
all over the top of the strut where the shaft goes in?

If fresh, be 'very' suspicious of being scammed and dry it off, then
drive for a while and check it again.

If it is indeed blown, I think replacing them in pairs is the best to
keep the side to side spring/shock rate the same.

My $0.02,

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
Canadian Off Road Trips Photos:  Non members can still view!
Jan/06 http://www.imagestation.com/album/pictures.html?id=2115147590
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Any reason why they said to change all four?  I could understand
recommending that they be changed in pairs, but why all four?

Also I'd second the advice to look at it yourself.  Or better yet,
first bounce test the vehicle.  Does the damping feel good and even at
all four corners?  Once you get a corner bouncing up and down, let
go.  it should settle to a stop very quickly, and not keep bouncing at
all.  (My Ford pickup with new shocks does oscillate once and then
stop when I do this.  I'm not nuts about it but I will have to accept
that that's what it's supposed to do.)  If it passes that test I would
wipe any evident oil off the strut and keep driving, if it doesn't
reappear I would have to say that either the shop made a mistake or
they're trying to scam you.  I hate to accuse a shop without any
knowledge but a Usenet post, but the advice to replace all four does
not sit right with me.

nate

nate

More info needed.
How many miles?
What kind of roads?
If your vehicle has 75,000+ miles or driven over very rough
roads then I would say replace all 4.
If you vehicle only has 5,000 miles and driven only on
smooth streets then I would say replace the one strut only.

How many miles on the car?  Probably not too many (<50k), so it sounds like
you've been scammed but didn't fall for it.  Clean the "bad" one up with a
rag and watch it for a few weeks.

If the leak doesn't return, it's fine. And, don't go back to that shop.

Bad struts are obvious and dangerous. As you go over a washboard in the
road, the car will dance into the other lane, or at least mine did, but by
that time it had close to 100k on the original struts.