I just replaced a whole lot of parts in my 2005 V50 (same as S40) front end. The lower control arms, struts, strut mounts and both axles. I did not replace the tie rod ends because they felt very solid (and still do).

The issue I have is that I've got a little bit of shake as I come up to highways speed - I'd say it seems to happen at 50-60mph. Not a horrible death wobble (like my old Jeep), but still a lot more shake than a vehicle with so many new parts should have. Oddly, this shake seems to come and go - sometimes bad enough that you can clearly see my hand moving as the wheel shakes, and other times perfectly smooth with no shake at all.

I put it up on ramps (so the tires act like they're on the ground), and had the wife saw the wheel back and forth a few inches (beyond just taking up any slack, but not enough to move the wheels more than the tiniest bit). It's the same with the engine running, or not.

There's a distinct metallic clunk when the steering goes back and forth across center - but I can't feel any play in either tie rod end, or movement in the steering rack, though I didn't pull the boots at the ends of the steering rack (which looks like it's been replaced at some point in the past). I do see the shaft coming through the firewall (from the steering wheel) "wobble" a bit as she's moving the wheel back and forth - seems excessive, but I can't say that it's "bad". Is there a bearing / bushing in the lower steering column shaft assembly?

Any guesses / similar experiences out there?

 

Had to crawl back under the car, and could clearly feel the metallic "clunk" in the left (driver's side in US) outer tie rod end, though there's clearly no movement in the outer tie rod end. I couldn't feel a similar sensation in the right tie rod end, which is leading me to believe that the problem is going to be play in the left side inner tie rod. Looks like a fairly straightforward fix, other than (sigh) having to pony up for another alignment.

 

OK - now I replaced the inner and outer tie rods - the old ones really didn't feel bad once I had access to the inners (required taking the boots off). Since I'm going to have to pop for another alignment, I went ahead and replaced the rear upper control ends (getting the inner bolt out on the right one caused me to think bad thoughts about Volvo designers, who apparently thought that snuggling a barely-reachable evap system (?) box right against the bolt head was a good idea). I didn't sweat the alignment too much, since I did a "driveway alignment. Basically, I laid a laser level on the rotor with both front wheels off, and the steering wheel centered. Then I marked where the laser hit the fenderwell on both sides. After replacing the tie rods, I just adjusted the laser back to the same position on both sides, and the steering seems to be perfect (though I'm going in for an alignment anyway - alignment is cheaper than tires). The same could be done with any straightedge or even a straight piece of wood - just mark where it contacts the fenderwell liner.

The "clunk" I was getting in the left tie rod end seems to be a function of the un-pressurized rack and pinion, which kind of makes sense. With the engine running and someone turning the steering wheel back and forth, there was no "clunk" any longer.

Took it out for another run down the freeway, and - while it's better - there was still a little shake in the wheel. Not much, and some folks would just ignore it. But... Since pretty much everything in the front end (axles, struts, strut mounts, lower control arms and ball joints and now tie rods) is new, I did not want to put up with ANY shake in the steering wheel. I lifted both sides and checked the vertical run-out on both front tires (near the center of the tread), and found that the left one was out 0.040" (40 thousandths), and the right 0.030" (this was from the "high spot" to the "low spot". It was hard to get a definitive number for the maximum allowable run-out (probably because it's tough to make a truly round tire, and tire manufacturers don't want to replace a big percentage of the tires they make because they exceed some magic number). I did some reading and came to the conclusion that having a road force balancing job done on (all) the wheels would probably "fix" this. Yeah, they'll still be a tiny bit egg-shaped, but apparently the RF balancing takes that into account. The closest place that does this is the Discount Tire shop, so in I go.

Just got a chance to take it down the freeway again (up to 80mph, errrrr, I mean to the legal speed limit of 65.000 mph officer, sir). Smooth as glass.

One question for those of you who have fiddled with the steering in an S40 (or V50 or C30) - there's a large nut on the bottom of the rack and pinion housing, on the part that's a continuation of the steering column input to the rack. Normally, this would be an adjustment to set the tension on the rack, but I couldn't find anything anywhere on how to adjust an S40 / V50 / C30 steering rack, and that nut was MEGAtight. Is that an adjustment or "just a nut"?