I've been searching the forum a lot, but I couldn't find the info I need...

My car (2000 Legacy Wagon, 2.0 engine, 5MT) has showed the typical symptoms of a dying center diff. But some three weeks ago, during a 3 hours trip, the car started to "whine", a noise coming from the front end of the car. At first it was slightly noticeable, right now the noise is pretty annoying at any speed over 10 mph. What makes me associate the noise with the viscous coupler at the center differential is that the noise is notorious only after a period of driving, the same period (about 10 minutes) that takes the car to show the VC failure symptoms. The whine/noise is like the normal sound of the reverse gear engaged, but you can hear it with the car coasting or with gears engaged; it won't change if you drive in straight line or around curves, the whine only changes to a higher pitch with speed increases, and viceversa.

My question is, can a center diff at a last stage of "demise" make this noise, or should I look the front diff, wheel bearings or another failure?

 

Thanks in advance!

does it make the noise also when you press the clutch pedal to the floor or does the noise go away (like while coasting/drifting down a hill)?

 

have you drained the gear oil and checked for signs of metal, sparkles, shavings, or worse?

 

could be clutch related too.

does it make the noise also when you press the clutch pedal to the floor or does the noise go away (like while coasting/drifting down a hill)?

 

have you drained the gear oil and checked for signs of metal, sparkles, shavings, or worse?

 

could be clutch related too.

 

The noise is always there when the car is moving, with the clutch pressed is the same.

One week ago I checked the gear oil level, it was below the "low" level. I refilled with 80W90, hoping that the noise would go away, but didn't note any change.

Thanks for answering!

Sounds like either a wheel bearing (unrelated) or the rear input shaft bearing on the tranny. Those often fail.

 

GD

My doubt about bearings is related to the noise starting after at least 5-10 minutes of driving; I guess a defective bearing would make noise at any temperature, or am I wrong??

Cold, thick gear oil may mask a rear input shaft bearing for a few minutes.

 

It definitely could be the center diff. Replace it and see.

 

GD

Ok, I'm gonna get a new center diff, anyway I have no choice since it is clear that is shot. Dealers down here charge about $2000 for the piece alone; if I can´t find a used one, I'll ask you guys for a good vendor in the States. Buying OEM parts in USA, including all taxes, fees, etc. is cheaper. I live in Chile, by the way.

 

 

Thanks!

I'm just lurking. I don't think it is the center diff, I am going towards the front actually. Has the lube oil always been full and changed regularly?

I bought the car in June with 1480000 km (92000 miles). I did 7000 km since then, and came to check the gear oil level only at 154000, when the noise started. I don't know if this is enough, or should I check the front diff lube? How do you do that? The car right know is sitting 100 miles away from the nearest dealer or shop; thats why I 'm trying to check the most by myself before making a trip with an uncertain end...

When a diff goes bad, it makes a whining noise. The farther gone it is the louder the whine. Once the radio can no longer drown it out it is pretty far gone.

 

You have to have a good ear to tell where it is coming from. I have only heard of one other center diff going bad (The diff itself not the viscous coupling) it happened rather quickly (Mileage wise) and without warning. It had a bad carrier bearing.

 

It is more typical for the front diff, if a diff is going to go bad, it is the front.

 

There is a dipstick under the hood for checkign the diff/gear oil level. I do beleive it is on the drivers side I just do not recall where. If I saw it I could tell you but from memory I can not. Some one here will tell you where it is.

The noise is definetly coming front the front end of the car. For instance, if I roll down the front passenger window the noise is much more stronger than if I do the same with the rear passenger window. But since I bought the car it showed very evident signs of binding after certain amount of driving. Maybe this preexistant condition caused the supposed front diff failure?

I agree with others that it's not the VC. But if you need a new one drop me a PM and I'll pass along the phone number of the person I buy parts from. I paid $550 for my '97 Impreza's VC a while back. I'm not sure he can ship internationally but it can't hurt to try. Worst case i might have some shipping options for you. My son lives in Bolivia so I have a little bit of knowledge about that.

 

Just for grins, when is the last time that the transmission oil was changed (if ever)? Bearing noise from the front is more likely an alternator or compressor if you haven't investigated that yet.

Thank you edrach! I don't have any input on the car lubrication manteinance, the only thing I was told about was the timing belt change at 120000km...

 

Well, I guess I'm gonna have to get the front diff checked first. I forgot to mention that the noise came also with a very slight vibration of the steering wheel I didn't note before. I also have to say that the car with the transmission "cold" runs super smooth, without noises, vibrations or binding; sadly, this lasts for a few minutes.

'99 was a bad year for center diff's. I've seen/heard of quite a few failures. The last one I replaced - the spider gears were so far gone in the center diff that they demeshed and the car wouldn't move. Made some really, really aweful noises. Center diff was the *only* problem with it. Another member here is using that transmission with a good center diff from another '99 transmission with a broken reverse gear tooth.

 

GD

My major mistake was not getting the car thoroughly checked; at least I should have asked at this forum before getting an used AWD car... I see lots of time, work and money expenses in my future

 

I'll keep you informed (I'll try to post some pics)

 

Thanks!

OK two FYI's

 

Always make sure the tires are the same make brand and wear.

The 2nd is change the timing belt seals water pump all at 105,000 or less.

Ok, I'll follow your advice, thank you!

Don't know if posting youtube links is allowed...

but this is exactly the noise my car makes:

 

 

(Video is from another guy's car)

Damn i have no sound as i need a cable.

Certainly sounds like a bearing whine. Too high pitched for me to think it's the front differential. And since the wheels are off the ground, I don't think it's the center diff. Since the wheels are off the ground, I take it you don't hear the whine while in neutral (or Park) with the engine revving up and the wheels on the ground not turning.

I dont know if my other note got through. but I'll bet it is the pinion gear in the center diff... bad cage holding the roller bearings causes this*... the trans itself it ok but the center diff pinion gear is likely totally shot.

 

used trans is how I would fix it, good luck! quick and cheap fix actually...

4-600for the trans and ??? for the shipping.

I use the conn. wrecking yard for this kind of part b-c Ive always had good lick w/ them Toms or ??? cant remeber the other names but Toms in Conn has always sent me good parts... for really good prices...

 

* often from running w mismatched tires. yes mismatched tires do in fact hurt awd transmissions of the subaru design. Not a reason to avoid Subarus, just important that all the tires are within 1/3rd of an inch in height.

 

Good luck... have fun. Its only a 4 or 5 hr swap. No big deal.

Certainly sounds like a bearing whine. Too high pitched for me to think it's the front differential. And since the wheels are off the ground, I don't think it's the center diff. Since the wheels are off the ground, I take it you don't hear the whine while in neutral (or Park) with the engine revving up and the wheels on the ground not turning.

 

Pitch change with speed; like you said, I can't hear anything abnormal with the car not moving, revving the engine or not.

 

I found this video on youtube and used it as an example. I hope to make one myself during weekend.

I dont know if my other note got through. but I'll bet it is the pinion gear in the center diff... bad cage holding the roller bearings causes this*... the trans itself it ok but the center diff pinion gear is likely totally shot.

 

used trans is how I would fix it, good luck! quick and cheap fix actually...

4-600for the trans and ??? for the shipping.

I use the conn. wrecking yard for this kind of part b-c Ive always had good lick w/ them Toms or ??? cant remeber the other names but Toms in Conn has always sent me good parts... for really good prices...

 

* often from running w mismatched tires. yes mismatched tires do in fact hurt awd transmissions of the subaru design. Not a reason to avoid Subarus, just important that all the tires are within 1/3rd of an inch in height.

 

Good luck... have fun. Its only a 4 or 5 hr swap. No big deal.

 

Well, I bought the car 1 1/2 month ago and came with matched tires inflated at equal pressure (20 psi, maybe the seller was trying to hide something?).

For now, I see complicated to swap an entire tranny. I guess I'll end getting the car to the dealer and wait for the giant repair bill

Well, no news yet. I'm trying to find a good Subaru mechanic who can help me and my brother (a mechanic too, but he works at an oil refinery 120 miles away) to get the center diff out of the car.

 

Today I got a picture (taken from the drivers side)

 

 

Apparently there's a leak between the tranny case and the transfer. Another sign of a bad center diff, or something else?

 

Another question I have right now, do you recognize the tranny and the transfer case? The engine is an EJ20, 2000cc, and I wonder if the tranny is phase 1 or phase 2 (according to this http://www.subaruforester.org/vbulletin/f89/center-diffs-how-replace-them-46979/); I suspect EJ20's kept coming with phase 1 transmissions despite being post 1999...

 

That's a phase 2 because it has the wide case flange where the two halfs are bolted together.

 

Does it have the hi-lo range shift?