What are the signs of a bad center diff?

[trainergames]

I am asking because my car has been making noise's and i'm trying to find out what it is.

 

I am thinking it is either that or wheel bearings that need fixed.

 

IF it helps my car is a 2005 Impreza 2.5RS with an automatic transmission.

Edited November 17, 2016 by trainergames

[1 Lucky Texan]

jerking/bucking in tight maneuvering on dry pavement. (the car should be able to turn tight circles smoothly at idle, or just above idle speed)

 

as a test, there should be an empty slot in the fuse box under the hood. Placing a fuse in there will place the car in FWD mode. Check you manual - usually under spare tire use section.

 

Often, that will make a change in the way the car behaves and point to certain problems in the transmission or drivetrain.

Edited November 17, 2016 by 1 Lucky Texan

[joomanburning]

When is the car making these noises? Immediately upon driving, or after you've driven for a while? In any certain gear or RPM? What kind of noise is it making and can you tell where it's coming from? Try to be as specific as possible, because these AWD systems can make alot of different noise from alot of different places. We can go from there.

 

As 1 Lucky Texan stated above, the most common signs of a bad "center differential" is the jerking/bucking/strong shudder in tight cornering. This is known as "Torque Bind". Google it, see if the symptoms match. I think there are even some YouTube videos showcasing the sound a bound-up diff will make.

Install the FWD fuse, see if the noise goes away. This topic is widely covered on just about all of the forums as well, but without more information we can hardly begin to diagnose, especially over the web.

Edited November 17, 2016 by joomanburning

[idosubaru]

You should describe the symptoms exactly instead of ask "what are the symptoms of XYZ". Or if you have a compelling technical/mechanical reason to think you're hunch is correct - tell us why.

 

Yours doesn't sound like a center diff issue as sound is not a typical initial failure symptom.

 

Have yourself or someone stand outside the vehicle on the left/right or ride in the drivesr and passengers seat. If the noise is notably left/right it's wheel bearing or CV axle depending what you're troubleshooting. If it's notably center/back, it's something else.

Edited November 17, 2016 by grossgary

[trainergames]

jerking/bucking in tight maneuvering on dry pavement. (the car should be able to turn tight circles smoothly at idle, or just above idle speed)

 

as a test, there should be an empty slot in the fuse box under the hood. Placing a fuse in there will place the car in FWD mode. Check you manual - usually under spare tire use section.

 

Often, that will make a change in the way the car behaves and point to certain problems in the transmission or drivetrain.

 

 

When is the car making these noises? Immediately upon driving, or after you've driven for a while? In any certain gear or RPM? What kind of noise is it making and can you tell where it's coming from? Try to be as specific as possible, because these AWD systems can make alot of different noise from alot of different places. We can go from there.

 

As 1 Lucky Texan stated above, the most common signs of a bad "center differential" is the jerking/bucking/strong shudder in tight cornering. This is known as "Torque Bind". Google it, see if the symptoms match. I think there are even some YouTube videos showcasing the sound a bound-up diff will make.

Install the FWD fuse, see if the noise goes away. This topic is widely covered on just about all of the forums as well, but without more information we can hardly begin to diagnose, especially over the web.

 

 

You should describe the symptoms exactly instead of ask "what are the symptoms of XYZ". Or if you have a compelling technical/mechanical reason to think you're hunch is correct - tell us why.

 

Yours doesn't sound like a center diff issue as sound is not a typical initial failure symptom.

 

Have yourself or someone stand outside the vehicle on the left/right or ride in the drivesr and passengers seat. If the noise is notably left/right it's wheel bearing or CV axle depending what you're troubleshooting. If it's notably center/back, it's something else.

 

Sorry i had to go to the shortly after posting.

 

It is making the jerking and thunking at slow speeds when turning.

Also i recently had a nail in my front drivers tire,and when i put my donut on to drive to get it patched, the problem was worse,until i hit 60mph the the FWD light came on and it drove fine the rest of the way to the tire shop.

 

I don't know if these are related,but i do sometime hear a small thunk from the front passanger side when going over some bumps.

[idosubaru]

while turning - jerking/thunking - now we're getting somewhere. that's a lot different than "making noises".

 

it does sound like torque bind. you can search the forum for that word and find all about it.

 

installing the FWD fuse may or may not alleviate it, start there.

 

if it is torque bind change the fluid immediately, like 3 drain and refills.

Edited November 17, 2016 by grossgary

[1 Lucky Texan]

all 4 tires really must be the same brand/model/size and close to each other in wear. You use the FWD fuse when you install the donut spare. There ARE ways the system can fail even when you do all that correctly - Duty Solenoid C can be bad, wiring can be bad, the wet clutch pack can hang-up and not function correctly, etc.

 

you may have 2 or more problems, but it seems one of them is definitely torque bind. If it continues, the transmission can be severely damaged. If the FWD fuse is NOT in place, put a fuse in there. If you do that and STILL experience torque bind, might be best to have a Subaru experienced mechanic determine what the problem is and if the best approach might be a used transmission swapped-in.