Clonking from left front wheel / suspension
 

My '97 Box has developed a bit of a nasty clonk from the left front wheel / suspension, sort of one clonk per rotation of the wheel, clunk, clunk, clunk etc. Currently it only manifests itself when the steering is on full or very, very nearly full lock (and I think only when the steering is turned to the right).

No apparent symptoms when not on full lock, seems fine at low or high speeds. However, the clonk is very nasty when, say, parking the car and using full lock. You can feel it through the steering wheel, hear it, possibly even makes the car jump up a bit, almost like you were driving over something with the left front wheel only.

If it was a FWD car, I would have said CV joint for sure, but obviously there's no drive to the front wheel, so I assume no CV joints up front on the Box. Any thoughts?

Pull the front wheel and see if there's an impact area shown by new wear.
The wheel could have a slight flat spot and it's rubbing the strut tower at a certain turn point.

I have/had a similar issue with my 08 Cayman. When backing out of a parking space at full lock, the car will sometimes make a loud POP or clunk in the front end or even a couple of them. The first time this happened, I thought I had run over a soda can. According to the folks on PPBB, this is fairly common, especially in cold weather. As it was explained to me, it has to do with the alignment and angle of the front wheels, which lift slightly so they aren't totally flat to the ground, then you back up and it causes them to be pulled across the ground in a jerk rather than rolling smoothly. This is worse in cold weather because the tires are less pliable. My mechanic told me the same thing and said it was nothing to worry about. I avoid the problem by trying to avoid turning or backing at full lock in cold weather. So far, nothing has fallen off and no tire or wheel damage.

Have you checked your power steering fluid....?

Have your tire shop check the strut mount ... those bearings could be shot.

Check your ball joints

John Simion is correct - it's the Ackerman effect, an alignment thing that's exacerbated by cold weather and is more prevalent in cars with a light front end.