Congrats on the purchase and welcome. I am a fellow e36 owner as well. I have a 94 325i with over 315,000 miles on it.

If the X is wandering and everything suspension-wise is tight, it may be the tires. Some tires tend to do that. Wandering/tramline isn't an issue that comes up too often here. I noticed my 4.4i with the sport package felt a little bit like that after I installed my latest set of Pirelli tires, but it seems to have gotten better after they were broken in. I never had this issue with my Toyo's. The other thing to keep in mind is that you went from a much lighter, lower and probably tighter e36 to a bigger heavier "truck" with taller tires. It will feel more floaty than your last car. You can always upgrade the suspension and get larger wheels to help counter that. My X has the sport package and floaty is the last word I would use to describe it. It actually feels tighter than my e36.

I have about 115,000 on my original shocks and the ride is still tight, for what it's worth.

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Profeshenal spellar