Pontiac G6 Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #1
I have a 2007 G6 4cyl 4 door automatic bought new and now has 108,000 miles. Last week I was out of town and it developed a humming in the front end above 25 mph. My wife had the left wheel bearing replaced and it got slightly better she says, but not cured. When I got home I swapped tires front to rear and the sound is still in the front. The sound is definitely rotational-drive or neutral, on the gas or off, uphill or coasting, braking or driving-nothing matters it is a constant speed related humming. You can really hear it inside with windows up and a/c off. With windows down there is too much wind noise. It sounds like quiet mudgrips almost. Any suggestions? I can throw another wheelbearing at it, but I really don't think that is it. I am very mechanical, and my gut says this is not a wheelbearing. Is there any issues with differential carrier bearings in the transaxles on these? It has really been a good little car with no issues until now. Changed the trans fluid with Valvoline synthetic just before 100K. Tires are Michelin X-Energy with about 25K. Brake pads are at least 1/2 left. Half shalves look good-not loose, no clicking, boots are good. Thank you for any advice.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #2
One other thing I forgot, there is no vibration, just a humming sound like quiet mudgrips that changes with speed above 25 mph.
 

·
Registered
Joined
·
447 Posts
No idea if this could be your problem, but you mentioned that you put in valvoline synthetic in the tranny. Im not sure that that fluid meets DEX VI standards though, and if not that might be your problem
 

·
Registered
Joined
·
447 Posts
Okay, it was just a thought. Possibly the other wheel bearing then? Can you tell which side its coming from?

If not the wheel bearing it might be coming from the tires? Are the wheels properly aligned, when was last alignment? Are the tires properly inflated? Are the wheels properly seated and torqued to spec?
 

·
Registered
Joined
·
19 Posts
Discussion Starter #6
It is difficult to tell which side, almost like it is coming from the middle. It could be the other wheel bearing, but my gut says no. It would seem odd that they both fail at exactly the same time. As far as tires they are good- wearing evenly, inflated to 32, and balanced. I swapped front to rear and vise-versa and the noise did not change at all. It had an alignment 25k ago with the new tires. Guess I will take it in today and see what they say. I am afraid it is a differential carrier bearing in the transaxle, but hoping it is not.
 
1 - 7 of 7 Posts
Top