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Car Rattles When Moving

I have an Infiniti i35 with about 150,000 miles that has a grinding sound that the car makes when the car is in motion. If I come to a stop, it goes away. When I start to move, the sound comes back very slowly and increases with speed. The noise doesn’t go up but the grinding just goes faster. On the interstate, the steering wheel shakes a little and I can feel the gas pedal shaking too. What could this be?

My guess is front wheel bearing. If this is the grand prize winner, it needs to be fixed FAST!!! It is already shot, and could result in severe loss of control if the bearing grenades or locks up, especially if your driving it on the highway like this!! Get it in the shop NOW!!!

This does sound like a bad wheel bearing, and a really bad wheel bearing at that. This usually starts as a droning sound and can progress to the point of sounding like you are driving on rumble strips at all times. This is the point at which many people will find it to be intolerable enough to take it to the shop and find out what’s going on. If it sounds like a grinding sound and is shaking the car, you need to get the car to a shop ASAP. I would also suggest towing the car to the shop, not driving it. This problem sounds much too dangerous to be driving with.

BTW, if you doubt me, just know that I had this guy come to me to help with his car. The wheel bearing grenaded while driving, striping the CV joint and cracking the steering knuckle. The wheel was sitting at an odd angle, jammed in the wheel well. Luckily, this happened in a parking lot at slow speed. He said it had a weird grinding sound for a couple of weeks. I’d hate to see what happened if this bearing blew out at highway speed.

The last time I saw a vehicle in that condition I had to laugh (ok - there was no major accident & no one appeared to be hurt) because the vehicle was an auto parts store delivery pickup truck. Of all things! It was in a left turn lane are a traffic light with the wheel at 90 degrees jammed in the wheel well. I was guessing it was a ball joint, though I couldn’t do anything but drive by (lest I become a rubbernecking traffic problem).

Actually, come to think of it “rattles” was used in the subject line of the post, but “grinding” in the body of the post. Rattling could also be a bad ball joint. That, however, does not change the story! Danger!