Please help with Subaru diagnosis

[Thorn]

I have a 1997 Subaru Legacy sedan (AWD) with the 2.2L H-4 and a four-speed auto. The car has 235k miles on the clock.

Last week, I had exhaust trouble, and so I took the car in to my trusted independent mechanic, and he replaced one of the catalytic converters ($570 parts & labor). My wife picked up the car and brought it home, and when I got in it and put the car in reverse, I noticed somewhat of a "binding" noise, which sounded like it was coming from the transaxle/front suspension area. I crawled under the car and immediately noticed that my CV boot at the driver's side front tire was tore, and grease was splattered around.

I took the car back to the same mechanic, thinking that the axle assembly was responsible for the noise. The mechanic replaced the axle assembly ($227 parts & labor) and my wife picked up the car. Last night, I checked it out, and as soon as I put the car in reverse, I got the same binding/grinding noise. The noise lasts for like one or two seconds and disappears so long as the car doesn't move. However, when I release the brake and begin to move backward the noise is evident again.

Then it dawned on me that the noise occurs as soon as I shift to reverse even before the car moves. I doubt whether a bad CV joint would've caused that problem in the first place because the binding/grinding sound occurs even before I take my foot off the brake and allow the car to move.

I regulary maintain the transmission fluid and it is full and clean. The front axle fluid is also full. I didn't check the rear axle, but the noise is definitely toward the front/middle of the vehicle.

Any ideas? I am sort of disappointed with my trusted mechanic because he should have noticed the noise when he had the car and investigated further. There are a few guys working there now, and perhaps I got someone not as good. Could anything have been damaged when they lifted the car to repair the exhaust, because I didn't have this problem until after I got the car back the first time? I'm guessing it is just coincidence.

I guess I am due for a replacement, but I would hate to not get at least close to another year out of the vehicle after just sinking $800 into it.

 

[Dad2leia]

Well, at least you didn't get taken on the parts that your mechanic did install, as it does sound like you did need those parts.

Maybe it might be something with the all wheel drive system itself. Have you ever done the fluid in the read axle?

 

[Thorn]

Yes, about 1 1/2 or two years ago, I replaced the rear axle fluid with Amsoil synthetic. I have never noticed any leaks around the rear axle either. However, there is evidence of weeping fluids throughout the engine bay/transaxle area, but it's been that way for years.

A Subaru specialist once told me that "if it ain't leakin', it ain't a Subaru". However, from what I understand, this weeping of oil is "normal" and usually doesn't cause trouble.

 

[Dad2leia]

Well, I hate to say this, as I know how most of us feel 'round here about dealers, but I would suggest taking to a "respectable" dealer, and give the all wheel drive system a look see. It could just be something is up with your reverse gear (I've had two of them go, but they were in Chrysler products), or maybe the clutch packs not liking going backwards anymore.

Maybe someone else who knows about Suburu's a little more than I do will offer some more advice.

 

[alanu]

alot of subaru's have a separate diff in their transmission s up front. See if you have oil in it. Its common for those diffs to leak dry an grenade the trans.

Subaru's are great when they work. Maintenance is usually higher for those vehicles since they are not the common engine configuration.

 

[drivewaytech]

Thorn, I don't know if our sounds are from the same cause, but my 1990 Subaru Legacy did the exact same thing. Never could really pinpoint the problem. The good news is that it made this sound for the three years I drove it. It made that sound for the two years my neighbor owned it (bought it from him). And it is still making that sound today. The car has managed to rack up over 360K miles and still runs strong. I somewhat wish I had not given that car away. No way to know if our sounds indicate the existance of the same problem, but I wouldn't sweat getting another years service from the car.

 

[Thorn]

alanu,

I checked the front diff oil and the transmission fluid, and both are full and look clean.

drivewaytech,

That's good to know, and hopefully I can drive it at least until next year's 2008 model clearance deals.

Would you recommend getting an estimate on a fix and then setting a limit as to what I would spend to get it fixed? Being that it has 235k miles, I don't think I would want to drop a few grand on a new transmission; but I already have $800 into it in the last few days.

At what cost should I consider replacing instead of repairing?

 

[meep]

Is this a rolling binding noise? Could it be the exh system rubbing on the driveline? Does noise change with speed in R? Could it be heat shield rattle?

The 5spd subies use a center diff with viscous lock, but the ATs are basically a FWD with electronic clutch to rear. IF you're concerned about an AWD problem, you can disabled the AWD by installing a fuse in the AWD-disable port...passenger side of engine bay at the firewall if memory serves. May need to look the exact loc up for the '90 model. You can drive it like that indefinently if you want. If that makes the noise go away, it points towards the AWD. I don't think that'll be the problem... but it can narrow the field.

m

 

[meep]

Also, could it be an internally faulty cat, since exh wk just done?

 

[Thorn]

Thanks for the suggestions. I know exactly where the fuse location is that you are talking about. I remember reading about it in the owner's manual 10 years ago when I bought the car. Supposedly, if you get a flat tire and change it to the donut, you are supposed to add or remove the fuse (I don't remember which) in order to disbale the AWD while using the donut. That's a great idea and may at least help me with the process of elimination.

It doesn't sound exhaust-related or like a rattling heat shield. Imagine what a solid clunk or thunk would sound and feel like, but the difference is that instead of being one solid clunk/thunk when placed in reverse, it sort of sounds interrupted like something isn't meshing together properly, yet it sort of has the feel or "heft" of a clunk.

I'm not sure about a faulty cat because it only happens in reverse.

 

[alreadygone]

Done lots of cat. con. replacements over the years. It is SO EASYto allow touching of parts that will "bump", "shake", "rattle", "grind",against each other I'd almost bet your new noise is somehow related to cat replacement. Throwing money at it's not a good idea, but just too big a coincidence to not have it put back on a weight-on-suspension style rack and do a close examination. Were it a comeback at my shop, I'd raise it, get a TRUSTED assistant to ride it up and start on rack, engage reverse while I listened from underneath.

bob

 

[Thorn]

Thanks. It may be at least a few days until I can have it checked out. I'll let you all know if they find the problem.

 

[sprintman]

Well I have a 7.5 year old Outback 2.5 and it sure does not leak any fluids. Sounds like you have a problem

 

[dhise]

Head over to USMB. There are plenty of people there who know Subaru's very well.

-Doug