2006 Legacy Front Clunking/Juddering

[Shuffleboy]

Hi all. Have searched multiple threads, and would like to have my own for this issue.

 

I'm based in New Zealand. Car is 2006 Legacy Sedan. EJ203. 4eat Auto. 172000 KMs done. Jap import. Car is in overall very tidy shape and appear to have been maintained well in Japan before my 4.5 years of ownership.

 

Over the last 6 months or so,there's been a clunking noise from the front left wheel area, notably when taking off doing a reasonably tight right hand turn. Last weekend when pulling out of a mall carpark on very smooth, squeaky seal, it really started to judder and grind, it's difficult to explain the sound and feel. This was a very slow turn.

 

Have changed brake pads myself about a year ago. Inspected them again, and slide pins. All. Seem functional and orderly. Wheels aligned a year or so ago

 

Have emptied and refilled power steering fluid a few times, to get a reasonably nice colour fluid.

 

Tyres on front are newish, on rear not as new but still in good order. Psi all up correctly.

 

However....noticed a few weeks ago that the outside edge of the front left tyre has gone bald. Tyres still has plenty of life left but the outside wear is very apparent. Front right tyre fine.

 

I rotated the tyres to eliminate options. Problem remained.

 

Put fuse in FWD holder. Problem seems to have completely disappeared! But I'm confused. Why would torque bind only affect one front side? What has caused the outside wear of the front left tyre and not the right?

 

Could this also be: front CV joint/s (and why would that disappear with FWD fuse in).

 

Could it be front differential?

 

Could it be auto trans duty solenoid stuffed?

 

Maybe something like tie rods or ball joints?

 

Any advice from you folk would be much appreciated. I like to fix my own cars but suspension/ gearbox issues are not a strength as yet.

 

Thanks in advance!

[silverton]

Replace your front ball joints, front axles, and the transfer clutches in your center diff.

[Shuffleboy]

Thank you for your reply.

 

I am slightly concerned regarding the amount of repairs you suggest are needed.

 

I didn't think the 4eat had a Centre Differential as such, more like a MP clutch pack? And if that is indeed the issue, why would I need to replace ball joints and both front Axles?

 

I do appreciate your input for me. I just am shocked that this fault is caused by 3 things and not one!

[Max Capacity]

Get under the car and shake the left axle at the joints areas, see how much movement you have.

 

FWIW, my wagon did a shutter thing once many yeas ago while backing out of a parking spot...it only did it once as far as I recall.

[silverton]

you're mentioning clunking noises from the front, though you do say they disappear once the FWD fuse is in.

 

If it were my car i would replace the three things I mentioned one at a time to chase it down. Start with the transfer clutches (due to fwd fuse alleviating symptoms), then ball joints, then axles. really you should do the ball joints and axles at the same time since you need to take the ball joint out halfway anyhow to do the axle replacement.

 

Bottom line, if putting the FWD fuse in makes your car feel better while turning, the transfer clutches are definitely going bad. You are correct about the center diff being a clutch pack, it's called a transfer clutch by subaru. And it's a lot easier to replace than it looks.

[Max Capacity]

I'm not an automatic guy, but you say, Put fuse in FWD holder. Problem seems to have completely disappeared!

 

Why would you drive without that fuse in place. It seems to me you caused the issue by removing that fuse.

 

 

If your front tires are wearing, have an "alignment shop tell you what's wrong".

[apexi]

Is the tread depth of all four tires within 3mm or so of each other? I'm thinking the tread depth difference between the fronts and rears is too much, which is why the problem goes away when the FWD fuse is installed.

Edited July 1, 2022 by apexi

[Max Capacity]

Good find ^

[ashwinearl]

On 6/30/2022 at 3:06 AM, Shuffleboy said:

Hi all. Have searched multiple threads, and would like to have my own for this issue.

 

I'm based in New Zealand. Car is 2006 Legacy Sedan. EJ203. 4eat Auto. 172000 KMs done. Jap import. Car is in overall very tidy shape and appear to have been maintained well in Japan before my 4.5 years of ownership.

 

Over the last 6 months or so,there's been a clunking noise from the front left wheel area, notably when taking off doing a reasonably tight right hand turn. Last weekend when pulling out of a mall carpark on very smooth, squeaky seal, it really started to judder and grind, it's difficult to explain the sound and feel. This was a very slow turn.

 

I have a similar issue where I get a klunk/shudder on sharp turns slow speed, on rough pavement. I've never been able to figure out.  I've collected links to threads similar issues.  Maybe they can be of help or provide some insight:

http://legacygt.com/forums/showthread.php/alarming-steering-clunk-rattle-218456.html?t=218456&highlight=steering+rack+rattle

http://legacygt.com/forums/showthread.php/popping-noise-while-cornering-65851.html?t=65851&highlight=steering+rack+klunk

http://legacygt.com/forums/showthread.php/knocking-front-suspension-106252.html?p=5458202#post5458202

http://legacygt.com/forums/showthread.php/anyone-had-front-end-clunkingi-189348.html

http://www.subaruoutback.org/forums/109-gen-3-2005-2009/36908-new-possible-fix-clunky-suspension-steering-box-problem.html

http://www.subaruoutback.org/forums/66-problems-maintenance/25382-steering-rack-clunk-begone-fix-inside-2.html

[lagwagon]

On 7/1/2022 at 8:54 AM, Max Capacity said:

I'm not an automatic guy, but you say, Put fuse in FWD holder. Problem seems to have completely disappeared!

 

Why would you drive without that fuse in place. It seems to me you caused the issue by removing that fuse.

 

 

If your front tires are wearing, have an "alignment shop tell you what's wrong".

The fuse is for diagnostics only (or if you need to put a different sized tire on the rear, like after a blow out). Putting the fuse in makes the clutches disengage and the car is FWD only. Some people used to do this for fuel economy as well but the rear driveline is still spinning, just not directly from the drive shaft anymore, so savings should be negligible.

 

If putting the car in FWD solves the problem, there is an issue with front to rear tire wear, or an issue in the driveline from the center differential (planetary gears/transfer clutch) back. A worn front suspension component causing uneven tire wear should be easy to figure out (which it honestly sounds like the OPs case from the description of one tire wear more than the others). It could even be a really bad alignment on good parts causing the tire wear issue.

 

It could be the transfer clutch or rear diff locking improperly (vlsd). I would not expect a front axle to be related if adding the fuse solves the problem since they are still being driven and a worn CV joint or damaged front diff would still click or pop.