Found bolt in bottom of rear diff!

[Vikingbruno]

Just picked up a 98 legacy l with 182,000 miles for 300 dollars.knew front axles were shot and replaced them today.rear diff. Lube level was low and decided to change oil.When diff. Was empty i noticed a loose bolt on bottom!i was able to fish it out with a pair of needlenose but WTF!no noise,shavings or clues where it came from.any suggestions on what to look for.rear seems to move ok.Are wheels supposed to move certain way with rear jacked up?my first subaru since 83 dl back in 88.also can i just put fwd fuse in this car?where is it located.what does it do,is it ok to keep in fwd mode,better mileage until snow falls?please help!

[Stang70Fastback]

With regards to the FWD fuse. It is located in the engine bay. Looking in from the front it is in the upper left corner (passenger side). It's just a little black plastic fuse holder with a cap that says 'FWD' on it.

It disengages the power going to the rear via a solenoid and a clutch pack. There are debates about how good this is for your car. The vehicle is not designed to send 100% of the power to the front end under hard acceleration and it is possible you could do damage, or at least wear parts out significantly faster if you daily drive it this way. It is really only meant as a diagnostic tool or to be used in the event of a flat tire.

It won't save you any mileage because you aren't really disengaging any part of the drive-train from the road. The rear wheels will still spin the rear axles, rear diff, and the drive-shaft, so you aren't magically going to make that extra friction, rotational inertial, and physical mass suddenly disappear. You're simply making it useless, dead weight, so you might as well keep it connected.

If that rear diff starts having issues as a result of what you mentioned, FWD mode won't really do anything to help you; you'll still have issues with the rear end binding up. FWD mode WILL help keep any shock from sudden binding from propagating up through the transmission, engine, and front diff, but it won't solve your problem.

[Zues Marine]

^this. also, the manual states to use that if you need to dolly the car for only a few miles but if you ever need to tow the car at all, the rear diff is connected to the driverline by 4 12mm bolts, the security of that being off is worth the 10 extra minutes to me

[snederhiser]

Hello;

Check the shaft that the spyder gears run on. Some diffs use a bolt to lock that shaft, Steven.