My 2003 AWD CRV (I forget what code Honda uses to denote that model) has had this issue for about a year. In my case I noticed it after getting a brand new set of Bridgestones at Costco. Tires where stock size on the stock Honda 5 spoke aluminum rims that come with this car. My vibes happened at 35 to 45 MPH, depending on the air pressure in the tire. At about 26 psi the vibe was at the slower speed, at 35 psi the vibration was at about 45 mph. In my case it was a pronounced amount of vibration if the car was driven through that speed slowly, if the car was powered through it as in a freeway on ramp type acceleration then the vibe was pretty much non existent on the way to a faster seed. I had the tires rebalanced by Costco, then Discount Tire, then Sears and finally by a small shop in Phoenix that had a force balance machine. I had the car aligned, I had the tires rotated. I rebuilt the front end with new struts (found the right one had started to leak) new control arm bushings, new brakes and rotors and new tie rod ends. All of these fixes / changes would have the result of making the problem go away for a few hours or days then it would come back.
I took the tires back to Costco because the force balance revealed that at least one tire had issues they considered bad but not horrible. We bought a new set of Michelin's with the 90k mile warranty and finally the problem seems to have diminished, but it hasn't gone away. I have also bought the Honda wrench and adjusted the steering rack free play just recently and am finally at a point where we are giving up. The vibe is finally at a low point that is acceptable.
My next step might be replacing the steering rack. If I raise the car and wiggle the wheels back and forth (left and right) I can see a slight amount of movement at the place where the tie rods come together at the rack, and I mean slight. Trying to figure out if that is standard or mileage induced and if I want to spend money on a steering rack, if I remember correctly Honda wants a major chunk of money for that!
By the way, the dealer has no helpful clue. They asked about transmission fluid and I told them I replaced it at about 75K. Maybe I'll replace it again?
