Random grinding noise-Transmission? Diff?

[Inca]

Hey all. I'm hoping someone has ideas about this. I have a 92 Legacy with standard transmission and 274k miles. I was driving home from town today, and twice had a grinding noise occur. It sounded like maybe gears grinding in the transmission or diff. I was driving fairly straight both times, once in 2nd gear, once in 4th. Both times, I immediately pulled the car out of gear, let it coast a little, then put it back in gear. When I put it back in gear, it seemed completely fine. When I got home, I checked the transaxle oil, and it was low, a couple mm below the low mark on the dipstick. Also, the big clamp holding the CV boot to the passenger side inner CV joint was missing, and there was axle grease leaking out, and there seemed to be a lot of oil on the lower transaxle and steering gear, though I do have a mild engine oil leak that I already know about. Also, there was definitely some play in the stub axles coming out of the diff that the inner CV joints attach to. I don't remember if they were like that when I did the clutch 4 years ago, but it sure seemed like a lot of play. Both sides were the same. Anyone had this happen to them? Any ideas what's going on? I clearly have a CV axle problem, but I don't want to buy a new one and put it in only to find out that the transmission or diff is bad.

[wtdash]

It's not a definitive test, but if you drive slowly and turn the wheels - like taking a left or right turn - does it 'click'. If so I'd suspect the CV's.

 

Did you drain the front diff/trans gear oil? See what comes out.

 

But I've heard (recently) that the Subaru 5-speeds are not necessarily the strongest. And at 274K you've likely put it thru its paces. It does 'sound' like the front diff is wearing out.

 

If you do go for a replacement note that the '96-'99 Subarus w/the 2.5 (not 2.2) AND 5-speed all used the same ratio: 4.11 (to match your rear diff - assuming AWD?). If you can't find a '90-'94 trans.

[Inca]

Thanks! I'll check that oil. I was thinking that since the noise stopped when I took it out of gear that maybe it was coming from the transmission. Good to know that the later transmissions are compatible with 2.5 engine, but I've got the 2.2 in mine.

I was hoping someone here had dealt with this exact thing, since all the searches I made for this only brought up problems with a constant grinding noise, not intermittent.

[wtdash]

transmissions are compatible with 2.5 engine, but I've got the 2.2 in mine.

 

Yep...and I know that the '90-'94 are 2.2...and they are the same ratio as yours....only the EJ22T/ 2.2 turbo is different - 3.90 (for both AT and Manual).

 

GL,

TD