differential issue??? what do I do please help.

[KodiHamill]

My fiancees grandparents bougtht us a 2002 outback as a wedding gift. Ive had 4 subies before this one and never a big problem. but this one has a whine whenever we give it gas and the whine gets louder as we go at higer speeds but will stop if put in nutrel or if we let off the gas. Her grandpa says this is the rear differential and not to worry about it.I didnt listen and wanted to fix it so I dont have stress or to hear the whine anymore. but I found some threads on here where that happened and then the transmission blew.

 

my question is can I replace the differential without replacing the whole transmission??? and if so how much will it cost for a shop to do this??? and will driving it this way blow the transmission? also if we do replace the differential and the whine is gone are we good,or should i still be worried about the tranny? this is scary for us because we dont have money to get a different car or replace a whole transmission. the subie has 140k on it and is in emaculate condition. the check engine light has come on,I'm guessing due to this issue since everything else seems great.

[WoodsWagon]

Automatic or manual transmission?

 

If it's an auto, the transmission and the front differential have separte dipsticks, the tranny is a red handled dipstick by the firewall on the drivers side and the front diff is a yellow handled dipstick right on the passenger side of the tranny above the axle on that side.

 

If a shop drained and filled fluid on the tranny or front diff they can often mix up which fluid goes where, or leave the front diff dry. Check the fluids in each, following the owners manual.

 

Rear diffs rarely fail, and if you put the FWD fuse in the the whine should go away. If the whine stays with the FWD fuse in, then it's a front diff or transmission issue.

 

If it's a manual transmisson, the input shaft bearings tend to whine on some of them. Those are a crapshoot, sometimes they'll go forever that way, sometimes the whining is because the nut is threading off the end of the mainshaft.

[KodiHamill]

its an auto,and i checked the dipstick it does have fluid in it. what is an FWD fuse? you mean like an electrical fuse?

[Fairtax4me]

Either auto or manual is just not worth ripping into the trans (auto is much more difficult) to replace diff parts. It starts as a bad bearing, but when it starts making noise it has progressed into drive surface wear on the ring and pinion gears which requires replacement of both parts as well as the bearings in order to correct. There are other parts in the trans that need to be replaced since they basically get destroyed during disassembly. If you tear it down that far, you better just rebuild it and at that point it's just not worth the cost. You're looking at probably $3000 between parts and labor JUST for the rebuild, plus extra for removal and installation, depending on where you take it.

 

The better option is to replace it with a rebuilt unit, or just a used unit from a junkyard.

 

Try what 91Loyale said first. Check fluid levels and try to isolate whether it is front or rear diff making the noise.

 

The FWD (Front Wheel Drive) fuse is used to disable the AWD system on automatic transmission cars so that you can drive with the spare tire on the car and not cause damage to the center transfer unit. It is a fuse just like any other blade type. There is a small black holder on rear of the passenger strut tower under the hood that should say "FWD" on it. The fuse holder should be EMPTY. You put a fuse in (use one of the spares from the interior fuse panel) to make the transmission disable the transfer unit and work in only front wheel drive.

Edited September 27, 2010 by Fairtax4me

[GeneralDisorder]

I didnt listen and wanted to fix it so I dont have stress or to hear the whine anymore. but I found some threads on here where that happened and then the transmission blew.

 

It doesn't sound as if you know much of anything yet - you don't even know which part is for *sure* making this noise. You mention both the front and the rear differential and the transmission yet they are completely distinct items though the transmission and front diff are actually integrated into a single "transaxle" unit.

 

I'll tell you what I tell everone that poses this type of question to me - IE: "what do I do about sound X?"..... Answer: "You wait till it gets loud enough that you can figure out FOR SURE what component is making the noise."

 

Differential failure's on Subaru's are very uncommon. Front diff failure on automatic's is often due to improper fluid changes/filling as noted above. Otherwise they are not known to fail.

 

And no - the check engine light has NOTHING to do with any mechanical whining noises your car is making. The engine computer has no monitoring systems with which to detect that nor would it care. After all - it's a check ENGINE light not a check transmission light now isn't it? If there were a detectable problem with the electronics of the transmission the ATF Temp light would flash to indicate an error code has been set inside the TCU (transmission control unit) - but again it has no way to detect (nor reason to care) about any mechanical noises being made by your drivetrain.

 

GD

Edited September 27, 2010 by GeneralDisorder

[1-3-2-4]

My front diff on my 03 Forester XS blew up because of the oil seal If all I did was checked it before I left I would of still had the car :-/