Recently I have purchased a 1990 Subaru Legacy LS Automatic AWD. And I have been needing to replace all the fluids in the drivetrain. But after looking at the Quick Lubrication Guide (scans below) I am a bit confused what fluid goes in the automatic trans, front differential, and rear differential. Now termanology wise I am a bit confused, from my understanding:

 

Automatic Trans = Transaxle = GL-5

Front Differential = Final Drive = GL-5

Rear Differential = Rear Differential (hehe) = GL-5

 

Now the big question is, does the Automatic Transmission take GL-5 as its lubericant? It currently has ATF/Dextron/Red crap that the previous owner must have put in. A big factor here is that the Transmission has a hard time shifting into Second and Fourth and slips under heavey acceleration.

 

Umm - do not put API GL-5 in your auto transmission - that would be AF3 that you would use (something Dexron III/ATF III I assume - but don't know - yes it is red, and the stuff isn't crap when maintained) - API GL-5 oil has sulfur in it, and would completely destroy your transmission (eat up everything)

 

the API GL-5 goes in the front diff of the auto tranny, and the rear diff - I have noticed a few errors (typos/formatting) in my FSM - this would not be the first

 

your transmission problems sound like the previous owner drove the car hard - or that he/she never changed the tranny fluid - which is something critical on Soobs

Wow!! That is an overly wide image...

 

Anyways, on the Engines Service part of the image, on the right side, it says auto trans uses AF3, which I assume is ATF Dexron III. It DOES take ATF in the transmission section. Make sure that you don't confuse the fill/dipsticks.

thanks, GL-5 in a automatic transmission sounded VERY weird to me and these lube books do suck quite badly. I just wasnt sure since I'v never worked on a AWD car, automatic trans, or a subaru for a fact. Hopefully a fluid change will help the automatic trans or I discover something tommarow when its at my work on a lift.

 

 

edit: well this car has been on the owner merry-go-round. I know a female college student and a Indian has owned the car, both prolly beat the hell out of the thing before I stumbled upon it. Besides the trans, the car is in near mint condition and the motor purrs. for 250$ I consider it a steal.

That book is a Trans/Engine/Gear Box SS right? There should be a smaller one with a blue or red cover with the auto transmissions. Your shop sould have both.