'90 Legacy LS automatic transmission fluid and questions

[njvaldes]

Hello all. I recently purchased a 1990 Legacy LS Wagon from a couple who used it only to drive back and forth from their condo in Salt Lake City to Alta Ski Resort and back. At the time of purchase it had only 113k miles and they were the original owners. The car is in great shape and I hope to make it last for miles to come. I don't drive often but do plan to use it for highway trips and occasional times when AWD is required.

I'm fairly mechanically inclined and feel very comfortable working on older Japanese vehicles such as this one. This is my second 1st gen Legacy. A couple questions regarding the Auto tranny:

Even though they took good care of the vehicle and serviced it regularly I don't know that they knew much about the vehicle. I have most of the maintenance records. The previous owners stated they had the transmission replaced about 20k ago. I have the work receipt and I don't notice any problems. The power light did a flashing routine and after some searching found the diagnostic routine that someone here or on another Subaru forum posted. It also prompted me to check the atf fluid levels according to the manual. A couple questions regarding the Auto tranny:

1. The atf fluid is a bit harder to check than other fluids (I presume because of the angle of the dip stick and lower viscosity fluid?). I followed the routine for a hot fluid check. The dipstick had a solid line of fluid well below the 'low' mark on the hot side of the stick. There was a thin barely noticeable line a good way up the stick though. I don't think this 'counts' as being at a full level though. Thoughts?

2. I went to our local Napa (I live in a small rural town with only one auto store) and given that Dextron II has been gone awhile he recommended Max Life (full syn) multi-vehicle ATF for dex/merc, Mercon LV. I bought it and followed the procedure to top the fluid level off. Rechecked the dipstick using the recommended procedure and it seems to be a full 'line' on the dipstick that after drive a mile or so is a solid line of fluid the width of the stick and after half quart is up to the full line with only a small barely noticeable thin line extending past 'full'. I presume this is normal?

3. Is the fluid I used an okay substitute for Dextron II? All results I can find on various forums indicate yes but I know auto transmissions can be a finicky bunch.

4. As I mentioned I do most of my driving on the highway at cruising speed and make a couple 8 mile round trip runs to town for groceries or to take the dog hiking. It does not get heavy use. Exceptions are I occasionally take it off road for photo shoots where clearance allows. I'm keen to keep the underside washed afterwards but for this reason I feel I should probably change the atf fluid a bit more often than every 30k as those 50-100 mile stints do put a heavier strain on the transmission.

Apologies for the long first post. I just want to make this ole girl last as long as possible. Interior is nearly perfect and the car really does drive nice. Emissions passed with flying colors, well below the CO & CA state limits. I live in CO for three seasons and CA in the winter months so the car does not see true winter temps. Any other advice or recommendations are appreciated.

~Nick

[Legacy777]

Nick,

Welcome to the BBS.

Are you leaving the engine running while checking the ATF? If so and you've cycled through all the gears and back to park that's the right way procedure. Regarding the line, there should be a noticeable line that covers the entire dipstick. The little bit of fluid on the edges are not the actual level.

Regarding the fluid, it should be ok It should also not whether it's dextron III/IV compatible. If it is then yes it's fine.

[njvaldes]

Thanks for the help! I presume that is your site? If so, it's appreciated. Couple questions/comments:

When I follow the directions I get nothing but a fast blinking light when I follow the 'existing problem' protocol. I presume that is the 'blinking every 1/4 second is normal'?

When I follow the protocol for previous problems I get two long blinks followed by 4 short blinks. I presume this is equivalent to code '24'?

If that is the case, then that would indicate a Duty C Solenoid. I haven't notice any problems driving. Most of the miles are highway miles. Anyone care to advise?

Nick

[Legacy777]

Hi Nick,

Sorry for the delay in replying.

Yes, that's my site, and yes the fast steady blinking is indication that everything is normal.

For the previous problems, yes that would be code 24. If you don't have any current drivability issues I would suggest clearing the ECM/TCM memory so that the previous code memory is cleared so that way if you check it in the future you'll know that any codes that come up aren't old.