Front Wheel Hub

I find myself having difficulty diagnosing what is likely a simple problem; looking for some words of advice.

2003 Cadillac Seville STS. 135,000 miles. I bought the car just under a year ago with about 120,000 miles on it.

Shortly after I bought the car, I brought it in to have it aligned, as it pulled to the left slightly. The shop called me back and advised me that the tie rod ends and the right front bearing hub needed to be replaced before the alignment could be done properly. I did the work myself.

As of about a month ago, I’m getting what I’d describe as a “whump…whump…whump…whump…” sound as I drive coming from the front, which corresponds to vehicle speed, roughly one whump per wheel rotation. It makes the noise at all speeds. Only the frequency changes. Even if I let off the gas and coast, the sound doesn’t change, nor does it change when I accelerate.

I think it sounds like a front bearing. The sound is non-directional. First it sounds like it’s coming from the front left, then it sounds like the right. It’s really hard to tell. I’ve had a couple friends ride with me and none of them can decide which side they think it’s coming from. If I roll down the windows to try to hear better, the wind noise drowns out the sound.

I assumed it was the left one because I already replaced the right (admittedly with a cheap auto store part). I put the front of the car on jack stands with the engine off, put the car in neutral and turned the tires by hand. First I checked the tire tread to make sure there weren’t any bulges. Both front tires felt fine. While turning the wheels, I didn’t feel any resistance on either side. Both felt exactly the same to my hand. No sticky spots.

The right wheel is solid. No camber play that I can feel. On the left, there is a very slight camber wobble. Very slight, just a tick, but it’s noticeable. Again, this makes me think it’s the left side.

Now the final piece of evidence: when I drive and veer right, the sound goes away or mostly away. when I veer left, the sound gets louder. This test says to me that it’s the right side.

I rotated the tires front to back with no change in the sound.

So, in summary. Right side bearing hub is new, though suspect quality. No play in the wheel. Left side bearing hub has unknown history. A bit of play in the left wheel. Noise gets louder when I turn left, gets quieter when I turn right.

How can I tell which bearing might be going out, or am I barking up the wrong tree altogether? CV joint? Tires?


I always find the turning thing to be way too convincing. So I’d be betting on that new right side hub.

If you put it back up on stands, sometimes you can feel the roughness of the bearing vibrating through the front spring. I’d also be inclined to check it when cold. The grease will be stiffer and less likely to mask any problems.

Of course, sometimes you just can’t tell…

I’d bet on bad new part. seen it too many times, and your test is pretty much right on.

If you still have warranty on the replacement part, bring it back, and while you’re there, pick up a new one for the left side, too.


That was kinda my plan. It is under warranty, I called and checked. I can get a full refund. I plan to bring it back and replace both sides with better quality parts. Just in the past day or so the sound has gotten louder and it’s fairly evident that the noise is coming from the right, the side I installed the new hub a few months back.

Thanks for the advice, guys.


Just wondering - even with sealed bearing type hubs, there are normally still dust seals, at the very least on the inside. I don’t know if the caddy has them but if so, did you replace those when you did the hub? Perhaps the first one went from contamination and now this one…

Replaced the right side hub with a quality part and the noise disappeared. Thanks for all the suggestions.