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rear diff leak on my 02 Forester :(

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so.. noticed something hanging under my car the other day.. went to investigate, and found that both tank straps had rusted & snapped.. needless to say, she is grounded for the time being.. and possibly permanently... :banghead:

also noticed, while under the car inspecting those, that the front of the rear diff is wet with gear oil - the front being the skinny part the driveshaft connects to. I am going to assume that this means seals are shot, and this area could also be the source of the low growling i have been hearing for a long time that I have not been able to pinpoint.. (ie: bearings going kaput)

we did change the fluid in the rear diff last fall because of the growling noise, and other half said the stuff that came out was pretty clean looking, no chunks, not really even dirty looking. at that time, everything was still nice and dry. new fluid did not make any difference in the noise, either..

so.. now what? do i retire the car due to serious steel cancer underneath? or do i try to fix it? She has almost 270K on her, and still starts and runs very well.. but...

Yes, she is quite rusty under there, and the chances of getting things unbolted without breaking things are quite slim...

thoughts? opinions?

I'd move on.  You know more will be rusted then fuel tank.  Get a rust free one from out west/south. 

If it still runs and drives then sell it - sadly our areas are accustomed to rust and someone will likely pay for a running and driving A to B vehicle. 

You already know those diffs are a dime a dozen - swap a used one in if you somehow navigate that rusty tank/straps.  You could probably find some other steel straps to fish up through there to hold it.  

Pinion seal is kind of annoying to change, as the nut has a lot of torque on it, so holding it solid while removing requires a fixture of some sort. And, has to be retorqued precisely. I replaced one once with none of the right tools (I think I torqued it with it in the car and the back wheels on ramps), and the diff was noisy forever more after that.

 

That should be either a 4.111 or 4.444 gear ratio. These are stupid common, and pinion oil leaks are rare. You can likely get a used diff for cheap. I've had 4 out in the last year, without too many dramas ('98 Forester, '01 Forester, '97 Impreza that had had the strut tower fail due to rust, and '00 Outback that I was worried about subframe failure, these were all MN cars). The '97 Impreza, I had to pound 1mm undersized sockets onto a couple of the factory bolts to get them to come out, but wasn't too bad a job.

 

 

Or....you'd be surprised how little oil can leak and leave quite a smear on the outside of the diff. Check the fluid level periodically, and keep driving it. Assuming, of course, you mount your fuel tank somehow, I have not had to deal with failed tank straps, yet.

Lot's of nice Rust Free ones out in Colorado.  Happy to pick one up for you.  

Would even consider making the drive back.  From Okauchee, WI back in the day.  Family still in WI.

 

  • Author

The tank itself is not bad.. but the straps are a mess. new straps were not that much, but getting the old ones out could be interesting..

my concern is with the rear diff i guess - i know that bearings can make noise for a long time before failing completely, and it has been growling for about a year and half now, maybe a little longer.. and i would definitely go with a used one if we attempt to fix it.. still not sure about it at this point.

also looking at possibly picking up another cheap (under $4k) car for the time being.. looking at an 04 Forester at the moment, 180K & a 5 spd for $2500 - waiting for a call back on that.

Larry... be careful what you offer, LOL, we just might take you up on it! =P poked around on Denver craigslist a little... hmmm...

 

I post good ones on the USMB.  I'm in Colorado Springs, but look pretty much around Colorado everyday.  Good ones go Fast!

9 hours ago, heartless said:

my concern is with the rear diff i guess - i

Besides dust and debris falling in your ears, eyes, nose - they are easy to swap.  And widely available used.  Don't let a diff hinder you. 

Or get studded snow tires and run it FWD LOL. 

  • Author
8 hours ago, GeneralDisorder said:

They often leak through the splines rather than the seal being bad, and some RTV under the nut will cure it. 

GD

thanks for chiming in GD, but slightly less concerned about the leakage, more concerned about the growling, which i assume are the pinion bearings.. behind the seal

 

  • Author

and to add insult to injury, the other half's outback popped a brake line today..  :banghead:

three vehicles here, and all 3 are down..

the pickup has a bad water pump, my car has its issues noted above.. and now the brake lines on his.. cant win for losing, dang it

 

9 hours ago, heartless said:

and to add insult to injury, the other half's outback popped a brake line today..  :banghead:

three vehicles here, and all 3 are down..

the pickup has a bad water pump, my car has its issues noted above.. and now the brake lines on his.. cant win for losing, dang it

 

Oh my sorry. That’s poor timing. How do you go anywhere this week?

Both Subarus then appear to be down due to rust?  

Not helpful when you’re stuck but consider next Subaru from west or south. It’s some leg work but you’ll save yourself hours of work, parts, downtime and $ in the long run. So worth it.

 

  • Author
1 hour ago, idosubaru said:

Oh my sorry. That’s poor timing. How do you go anywhere this week?

Both Subarus then appear to be down due to rust?  

Not helpful when you’re stuck but consider next Subaru from west or south. It’s some leg work but you’ll save yourself hours of work, parts, downtime and $ in the long run. So worth it.

 

thankfully, he has a very generous boss who has no problem with him bringing a work truck home, and has also offered the use of a truck he has - if we can find the darn key for it.

the Outback is currently in shop to get brake line fixed, and should be ready in a day or two.

I personally, do not need to go anywhere again until Friday.. Outback should be done by then.

and I could, if absolutely necessary, drive the Forester. Have no idea how long those straps have been broken, could have been that way for a while now.. the back side of the tank is sitting on some rubber caps that are part of the rear suspension.. dont think it is going anywhere on that side. the front side is being held by the front half of the straps & the rock guards that are attached to the strap and the tank.  True, driving it with the tank sitting as it is, is probably not ideal, but it could be done if absolutely necessary.

and if all else fails.. well, we have a riding mower and a tractor, LOL :D

Hopefully a brake line should be straight forward and quick with no surprises. 

  • Author

And the 2004 will be coming home this weekend. :D

185K, 5 spd that runs and drives quite nicely.. good tires all around, interior is pretty clean.. seats could use a good cleaning, but no rips or tears.

a few minor battle scars on the body, and a little rust in the right rear wheel well..typical place.. but overall she is pretty clean for her age.

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