Hi all, 2011 Saab 9-3 XWD, currently 9k miles. Just purchased a month ago. Was previously a dealer loaner vehicle.
I have this noise coming from both sides of the rear when the car is in motion. I am unsure if it is just loud enough to sound like it is coming from both sides or if it is really coming from both sides.
It doesn’t start immediately, only after the car has been driven a bit. The noise is most noticeable between 5 mph and 10 mph. It is definitely a rotational sound (I can notice fluctuations in the noise as the wheel spins). It appears to come from both sides. When the car is in the air and the wheels are spinning their is no noise (according to the shop I have been to, I have not been present when this has been done), so that would mean it only occurs when the wheels are touching the road. It does not change when the brakes are applied but goes away immediately when the car comes to a stop. It occurs no matter which gear the car is in (automatic). It even makes the sound when the car is off but rolling.
I have taken it to the dealership and several other repair shops. They all take apart the brakes and inspect the drive train, but no one can find anything out of the ordinary.
It sounds to me like differential whine. Has anyone checked the fluid level in the differential?
And here’s mention of a potential seal issue in the differential:
So if the fluid has leaked out or become contaminated with moisture, that could do it.
At the very least, I would have the differential fluid changed and see if that helps…even if it’s supposed to never need changing. If the fluid is contaminated from a bad seal…then it needs changing.
It sounds too high pitched for a wheel bearing. Have they check that though? Being on a lift, that would take the weight off of the bearing and probably would be quiet. If the bearing is ok, then check the differential. Good luck
Will check the fluid level this weekend. Easy way to tell a leak from just moisture from the wet weather we have been having? I’ll also check the wheels for wiggle to see if it is the wheel bearings…but it would be weird to have 2 go at the same time.
Appears to be coming from the differential, also notice a clicking (can be felt and heard). I checked the fluid, it is full up to the fill hole and is clear. Smells clean. The bolt was magnetic and didn’t have any contaminants. Seal? Or bad Diff?
Wow, that sounds bad. If the fluid looks good and was full up, there may be a manufacturing defect inside the differential. Is there a powertrain warranty that would cover this? If not, you may be looking at rebuilding/replacing the differential on your own nickel. Or check the lemon laws in your state.
PS…also check the inner CV joints near the differential to make sure the noise(s) are not coming from them but from the differential itself. The clicking could be from a CV joint or the differential itself.
It is a 2011 but was sold as is unfortunately. I am going to have to take it in to the dealer (the same one that swore there was no noise) and show them the videos I guess.
Great job with the video, by the way. If you have a warranty of any kind, the video should be definitive enough to support a warranty claim. Be advised, however, that if the warranty is leftover manufacturer’s warranty you may be stuck paying for the repair. Saab is an orphan brand, which means there’s no Saab here anymore to reimburse a dealer for warranty repairs.