I started to feel a vibration with my 18inch wheels and thought it was a broken belt. I was told my rim had a bend in it. Decided to switch to a set of 20s. The vibration got worse, even after putting a new set of tires on the rims.
The vibration isnt always consistent but the longer I drive, the more I feel it to a point. It can get pretty heavy around 50-70. The steering wheels shakes from side to side and my passenger headrest moves quite a bit. I saw than Nathan had a vid about it possibly being a bushing but I am unsure.
Without spending an arm and a leg a mechanic I trust was thinking rear axles or drive shaft. I mentioned the video but looking under the car, we didn't see a great way to access without removing the heat shield. He is set to do that on wed.
Today when riding home, at one point I would feel the vibration and then it would stop for 1 or 2 seconds and start back up. I am at a loss on what the real issue is, any insight would be greatly appreciated.
When steering wheel shakes it have to do with the balancing of the wheels. You can have changed to wheels that actually are worse or unoriginal which doesnt fit properly to the hub. You may need spigot rings if that is what they are called. Also check rim concentricity and straightness.
Next up is wheel bearings which can be ruined if driving into a pothole.
But before you change almost the entire suspension, you can check the output shaft of your transmission. It is probably wobbly. This makes the passenger seat wobble too. I dont know if the output bearing can be changed without taking the transmission out of the car, but it is probable.
But first recheck those wheels