"Waaah Waah Waah" sound coming from rear wheel at low speed

Early 90’s Toyota Corolla.

I’ve been hearing this sound the past couple weeks coming from the rear of the car. Not related to the rpm, only occurs if the car is moving slowly – like when I’m driving in a parking lot, looking for a space. Occurs when turning, even slightly, but not when going dead-straight. It it intermittant, seems to occur more often on hot afternoons, never heard it all winter, or even now in the morning. Not that loud, but noticeable. Sounds a little bit like a vibration, sort of a buzzing sound, but more musical than a simple buzz.

The best way I can describe it is that it sounds almost exactly like that sound they make in kids cartoon shows on Saturday morning, when something bad happens, like one of the characters get hit on the head with a baseball bat …" waah waah waah" … sort of like a muted trumpet or muted trombone.

Rear wheel bearings? Brakes?

Guess I get the first wag, a heat sheild, then wheel bearing. Really until it can be inspected and diagnosed by a reliable mechanic we are all guessing.

I was thinking it might be the cat heat shield too. I’ll crawl under there this weekend and give it a shake. It will be easier to fix that than the wheel bearning. Thanks for the comment!

A rubber mallet beating on stuff might be helpful also.

Could be tire tread noise due to uneven wear from not rotating tires per the owner’s manual.

You might first try switching around a pair of tires to see if the noise changes positions. If so, suspect a tire tread problem.

I don’t think it’s the tires. They’re about 8 months old is all. And it doesn’t sound like a tire problem. Tire problems cause noises when the car is going 20-30 mph and higher, at least in my experience. Switchiing the tires is easy to do tho, so I’ll try it as part of my cat shield investigation this weekend since I have to jack the car up and stand it anyway.

I think – while I prefer it not be – I have this feeling it is one of the rear wheel bearings. Rear wheel bearings on Corolla’s are not the kind where you undo an axel bolt, remove a cotter pin, and slip them off. They are press-fitted such that they must pulled off the axel-rod with a special puller tool, and pressed on with a special presser tool. That’s what the shop manual says anyway. So I have 3 questions:

  1. Since it just started mis-behaving, what about rejuvenating the existing bearing? Anyone tried greasing a pressed on wheel bearing without removing it, by injecting grease here and there with one of those tiny pointed grease gun fittings? What about drenching it in gear oil? Or is that all dreamworld, a waste of time, never work, etc? Anyone with experience trying to rejuvenate a rear wheel bearing on a front wheel drive comments are appreciated.

Assuming #1 is just wishful thinking … and I actually have to replace the bad bearing w/a new one … which is probably the case …

  1. Removing the old bearings and races: I have a generic puller tool that I have used to pull the crankshaft pulley off the crankshaft, and it works ok for that. Do you think I can improvise something that would allow me to use that puller to remove the wheel bearing and the bearing races?

  2. Installing new bearings and races: I sometime have to replace drive shaft U-joints in my 1970’s Ford truck, which are press-fitted. They are supposed to be done with a press, but I don’t have a press. The way I do that is I find a socket sized just under the diameter, and I pound on it with a hammer, driving the old U-joint out. Then I do the same thing in reverse to drive the new U-joint in. That works ok for U-joints. Workable for these wheel bearings and races I wonder?

Hey I know this was a long time ago, but I’m getting the same thing - can you remember if you were able to determine what it was? Heat shield? Or bearings?

It turned out to be very simple, tire tread wear pattern had developed. Tires near end of life, so replaced all four tires, problem solved.

@mwsberdan_183137, suggest to look carefully at the tire tread. See any wear patterns?