n00b differential question

[jblair]

Last week, I purchased an automatic 1993 Legacy L Wagon AWD w/116K. I've owned 2nd gen. Mazda RX-7s (four to be exact) for the past four years, so these cars are completely new to me (I'm used to rotary engines).

Anyway, I'm taking my car in to the shop this week to have the differential fluid changed, and from what I understand there are two (three?) differentials -- a front and a rear. Do I have the fluid changed in both of them? Some things I've read say the front diff. is lubed by the transmission, but I'm not sure if that goes for our cars or not. I just don't want to sound like a dumbass when I take it in. Also, should I recommend a certain type of gear oil, and about how much should this cost?

I'm also wondering what all I should have them inspect when they have it on the lift. I'm thinking CV joints and tie rods, but is there anything else?

[Splinter]

Front diff is shared with the tranny only in the manual gearboxes

In the autos, they have their own oil. So do the rears. The center shares with the tranny.

[napphappy]

Only manuals have a center Diff. Autos use electronically controlled hydrolic clutch packs.

[jblair]

Thanks for the info. Any suggestions on what I should have them inspect while the car is on a lift? I'd rather spend the money now then later.

[entirelyturbo]

If it's manual, I would use plain old gear oil. 80W90. Some seem to like the synthetic stuff (actually, I have GM Synchromesh at work, so I might give that a whirl here before long), but I used Redline once and it ground 4th gear.

Double-check that there's no rust underneath while it's on a lift. It's probably leaking oil somewhere, so now would be a good time to try to identify it.

[jblair]

It's an automatic, and thanks for the note on the oil leak -- I'll check that out. Are there any locations on these car that are notorious for leaking oil?

[jblair]

So just to be clear, I do need to have the fluid changed on both the front and the rear differentials, correct?

[Subtle]

You dont know for sure when the last change was, so change the precious fluids in both diffs now and then on a regular basis

[bepa]

what's up? front and rear diff change the fuild. check for leaks like everyone said. you were checking out so struts for sale the other day. they did have a lot of miles, still four struts for a 100 dollars. the roads may be in better shape up north. enjoy your subaru. safe driving.

[Legacy777]

So just to be clear, I do need to have the fluid changed on both the front and the rear differentials, correct?

correct

[jblair]

Thanks. I'm taking it in tomorrow. They said it will be about $55 for both front and rear. I'm also having a tie-rod inspected because I think it's shot.

[jblair]

So I ended up spending $203 for an oil change, front and rear differential fluid change, automatic transmission fluid change, replacement of a missing brake caliper bolt (turns out it wasn't a tie rod making that noise) and inspection of various parts.

In the next month, I will also need a coolant flush, new thermostat, steering rack boot and rear brake pads and rotors. And it needs a new key because the old one is worn out and could possibly mess up the ignition switch. Fun stuff. But even with all of this stuff, I still got the car for a good deal.

Oh yeah, and they said that the engine leaks oil in about three different places, but it's not that big of a deal (especially considering it would cost about $1,300 to fix everything).

[bepa]

before giving any money to some one else, jaack up the car yourself. changing the oil pan gaskets is an easy enough repair. possible one of the oil line s to the cooler or another small lines is leaking. what did they said leaked? a lot of repairs on sabaru's are just time more then really hard repairs. in new york and a long trip to athens. I'll keep an eye out for more of your posts.

[jblair]

They said it leaked in the front, side and rear of the engine. The guy I bought it off of said he had the front seal (along with the timing belt) replaced a month or so ago. I guess they didn't do too swell of a job.

Leaking oil isn't a big concern to me. I drove two second gen. Mazda RX-7s for the past four years, so I'm plenty used to leaking oil. I just want my car to be safe and reliable (I have a son whose due in two weeks). I orderd the brakes, rotors and steering boots. I plan on doing the brakes myself and I might attempt the steering boots.

[bepa]

first things first. take a little time and tighten all the bolts you can get to. wipe down all of the under carriage. best to use glove when doing this. all that road grit and what else is there. good time to do an oil change as well. this being a subaru, check to see if oil is coming from the valve covers. also when the bolt gaskets done or are they passing oil thru the heads of the bolts.

back to the point, tighten all the bolts you can find. you do not have to over tighten them either. just tight! if the leak is coming from the front then you will have to remove the covers over the timing belt to see if crank shaft seal is leaking. I have done the front seal myseal, all the same I would work with someone who does them often to be safe. you can do it but this one I would do with assistance if it is one of your first.

also when you are looking behind the covers look at the cam shaft seals at this time. same thing wipe the area and run the car for a while with the covers off. see how much oil leaks. you will see as times goes on that you can fix most items on a subaru. they have good balance, flat four, good milage most of the time and no one is steal them in my part of nyc. be good and enjoy you zip.