Hi CarTalk Community, I’d like to solicit opinion on my 08 RX350 AWD growling sound. Recently, we drove to Fort Bragg through Highway 20 zigzag road. Few days later, I notice a growling sound when driving straight and the sound disappear when driving on a curve (or as long as you can tilt the steering wheel at least 15 degrees clockwise) and once you set your steering wheel straight again, the growling sound comes back and goes louder as you accelerate from 30 to 60 and even much louder past 60mph. Thought it was the tires, and since it has 65K miles on it, we decide to have all four (4) tires replaced but the condition persist. I read some discussion on this forum and suggest it was the wheel bearing. However, when you lift the car, and try to wiggle the wheel, it’s not unstable; it’s not shaking at all. The sound is really annoying because it’s so deep and fine that you can’t hear the radio sound anymore unless you turn it up higher. I’m not an expert on this area and would like to refrain from costly trial and error parts replacement. Any suggestions? Thanks in advance.
I will offer some ideas although I am not sure I can single one out for you. This sounds like a typically issue with a cv joint. However you normal hear the grinding when turning with a bad cv joint.
It could be the power steering pump or the rack and pinion. It could be the wheel bearing. I know that you said the wheel bearings don’t have any slop but it could be a possibility. Out of all these possibilities my favorite one is the CV joint has gone bad.
Your best bet is to take it in to a shop and tell them you think you have a bad cv joint and see if they can replicate the problem and suggest anything else that might be bad.
Thanks a lot for the suggestion. I’ll update you and the community once the issue gets resolved.
Check the rear end differential oil level.
Wrong , telling a shop what to fix is not a good practice. A person should describe the problem as best they can and let the shop mechanics do their job .
A sealed wheel bearing will usually start to growl before it shows a lot of play.
I hate to be the bearer of bad news but these are not symptoms of bad wheel bearings.
It can be the symptom of a differential going bad and although I don’t know the exact drive train setup, you probably have 3 differentials.
Thanks a lot for the suggestion
Had bad luck with that. Toyota Cressida was overheating. Happened once before and I found it was a cracked vacuum line in the climate control system in the engine compartment. A couple of years later same thing happened again and I traced it to a vacuum hose at the back of the dashboard climate control unit but I could not get to it so I decided to let the dealer experts fix it. They replaced the heater control valve and the radiator cap. Still overheating. Took it back and told them where the problem was and that fixed it. Another time I took my Dodge caravan to the dealer because of problems with the power rear hatch and their $95 computer diagnostic said “latch failure” , requiring a $400 latch assembly, plus labor. That was impossible because with manual assist, the power latch always released. The gas struts had weakened from age and were not pushing the hatch far enough away from the latch before it reset. I replaced them myself.
Thank you ALL for your suggestions and feedback. I brought my truck to the dealership for diagnostics and it was the compromised rear passenger wheel bearing creating the growling sound. The hub was replaced as well for $998 taxes included.