Hi, I have a 2000 Outback 2.5L 4EATII automatic 195,000 miles. In the last 50 miles or so I've started noticing a slight gear noise when coasting. It's not very loud but with the radio off it is noticeable. I feel no vibration. It seems to be coming from the transmission/front diff area. It seems related to wheel speed not engine rpm. To me it sounds sort of like pedaling a 10 speed bike backwards. It's not a whine, and it is not a grinding sound. It sounds more like two gears not meshed properly or gear teeth rubbing on something.

 

Coasting is when it is most noticeable. It does seem to be there very very very slightly under load as well. It seems to do it in gears 2,3,4 or coasting in neutral (auto trans). I didn't notice it in reverse, and locked into 1st it didn't seem to do it but I might just not have been able to hear it.

 

Thoughts? I checked the AT fluid level and front diff gear oils, both were at the right level and clean. The front axles seemed to be fine, no excess looseness, didn't seem like the stub shafts were coming out of the diff or anything. Thanks. I'm just trying to figure out if it's something to worry about and hoping it doesn't grenade or something on the highway.

Edited October 8, 201411 yr by porcupine73

Noise while coasting... only one like that I recall is a manual center-diff bearing noise while coasting.

Thanks Dave. Now it's doing it under load and when coasting. It's loud enough now that I don't feel safe going over about 45 mph with it. It's hard to tell exactly where its coming from but it seems loudest on the passenger side more up toward the firewall. I'm stopping driving it and have a shop look at it. I'm guessing if it's something in the trans or front diff that's going to be a couple grand by the time the trans comes out and another one goes back in. Not sure if its worth it, at this mileage, head gaskets never done and it does use coolant but I just keep it topped up, and nearly ready for another timing belt change.

Check your tire air pressure. I've noticed if mine get a little low from another, the rear differential makes a little whine. Next, I'd check the fluid in the rear diff and the front. Your tires are the same size, right? Are they wearing evenly?

Edited October 11, 201411 yr by Bushwick