oakman1437 Posted June 16, 2007 Share Posted June 16, 2007 Hello Everyone, I have a 1996 Legacy Outback AWD w/ 2.5 liter and 4EAT transmission that my son and I are restoring. The car has 171,000 miles and the biggest job appears to be a front differential with some chewed up gears. This was formerly my brother's car and the FWD fuse has been in for the last 40-50,000 miles because of problems with the rear differential. It was running ok until my brother said he heard a loud bang under the floorboard and it wasn't from anything he hit or ran over. After that, the car was jerking or pulling (almost as if something were out of round) in drive and not in reverse. He drove it home and replaced a CV joint thinking that would solve the problem but it didn't solve the problem. I drove the car back and forth a few times and noticed the jerking and loping but after I tried to drive it up a driveway with a bit of a steep incline, it seemed as if some gears disengaged (or broke) enough to leave me with a car going backwards down the driveway while making a loud noise as if a gear was trying to engage but the teeth were half chewed up. We've removed the transmission and can see through the dipstick hole on the front differential that some of the gears are chewed and going on toothless. I'm looking for the best and most economical way to get repair manual info and parts. Any and all help would be appreciated. Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted June 17, 2007 Share Posted June 17, 2007 Hello and welcome! It sounds to me like you're probably going to want to get a known good used 4EAT from a similar year Outback. Generally people treat the trans and front diff as a unit and don't try to service the front diff separately. If you do get a used trans, you must make sure it's final drive ratio (like 3.900) is the same as your existing rear diff or the AWD will get ruined in a hurry. One way to do that is to get the rear diff from the vehicle the used trans came out of. There are other options, such as Subaru rebuilds but those are going to be expensive. Trying to do internal work on the front diff and stuff doesn't sound like it will be economical, plus you don't know what else in teh drivetrain may have been damaged too. Quote Link to comment Share on other sites More sharing options...
ron917 Posted June 17, 2007 Share Posted June 17, 2007 Some guys are brave enought to rebuild the front diff.... http://subaruoutback.org/forums/showthread.php?s=&threadid=8718 Not for the feint of heart. I agree that it's probably not the best course of action unless you know the the rest of the unit is in good shape. The fact that the FWD fuse was in for 40-50 K due to other problems is troubling. Quote Link to comment Share on other sites More sharing options...
oakman1437 Posted June 17, 2007 Author Share Posted June 17, 2007 Hello and welcome! It sounds to me like you're probably going to want to get a known good used 4EAT from a similar year Outback. Generally people treat the trans and front diff as a unit and don't try to service the front diff separately. If you do get a used trans, you must make sure it's final drive ratio (like 3.900) is the same as your existing rear diff or the AWD will get ruined in a hurry. One way to do that is to get the rear diff from the vehicle the used trans came out of. There are other options, such as Subaru rebuilds but those are going to be expensive. Trying to do internal work on the front diff and stuff doesn't sound like it will be economical, plus you don't know what else in teh drivetrain may have been damaged too. Thanks for the welcome porcupine73! You're right about the Subaru rebuilds.....Expensive! The used trans and rear diff is a good option for us also but, since the entire drivetrain/diff combo also appears to be a scarce item, I think my son and I will start with taking a shot at this front diff and transmission. So far, I'm very impressed with the quality of the design, parts and materials on this Subaru Outback. My brother got 171,000 hard-driven miles (he put this horse up wet many times!) without ever thinking about gear oil. Thanks again for the reply! Quote Link to comment Share on other sites More sharing options...
porcupine73 Posted June 17, 2007 Share Posted June 17, 2007 If you can't find the 4EAT and Outback diffs, one from a Legacy may fit. It will have the Legacy drive ratios and your speedo may read low. Other years up to '98 may fit too but the wiring harnesses for the trans might not match up exactly. Quote Link to comment Share on other sites More sharing options...
nipper Posted June 17, 2007 Share Posted June 17, 2007 Welcome Your going to need a used tranny. Also the problem your brother had was not the rear diff, its something called torque bind. Search that subject and youll see the rear diff is fine. nipper Quote Link to comment Share on other sites More sharing options...
idosubaru Posted June 18, 2007 Share Posted June 18, 2007 nipper said everything i would have said, but more succinctly! Quote Link to comment Share on other sites More sharing options...
johnceggleston Posted June 18, 2007 Share Posted June 18, 2007 www.car-part.com here's a good place to start your search for used parts. these things aren't too scarce . sort your search by distance. another option would be to buy a wrecked outback with a 4eat. even if the trans in your car is good, you'll need front diff parts. as mentioned above, they usually come as a set. there is an ID plate under the hood on the driver's strut tower with your trans part number. an identical part will work, 97 and 98 outback will also work. what is your trans part number, TZ102Z2ABA? the 'bold 2' defines the final drive ratio, (actually it means it's a 2.5L engine but this defines the final drive ratio on automatics). legacy trans of the same years will work but you need the rear diff too. (legacy final drive is 1:4.11, outback is 1:4.44) i understand you and your son have more time than money, but i would hate to see you do the work on the diff, just to learn that the trans has problems. and the AWD unit already has torque bind. so 2 of the 3 sections in the transaxle need work, get a used one. Thanks for the welcome porcupine73! You're right about the Subaru rebuilds.....Expensive! The used trans and rear diff is a good option for us also but, since the entire drivetrain/diff combo also appears to be a scarce item, I think my son and I will start with taking a shot at this front diff and transmission. So far, I'm very impressed with the quality of the design, parts and materials on this Subaru Outback. My brother got 171,000 hard-driven miles (he put this horse up wet many times!) without ever thinking about gear oil. Thanks again for the reply! Quote Link to comment Share on other sites More sharing options...
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