CV or axle noise? Help please!

Hi guys, its been a pretty good stretch of fairly trouble free miles, but as I cross the 130k mark, I'm having a helluva time diagnosing a very annoying problem.

Car is a 2007 Legacy 2.5i (not GT) with a standard transmission.

Heres the scenario:

I first noticed when driving in the industrial park (30-40mph) a clicking/clunking that sounds a lot like a horse trotting and (and worse, rod knock). I got on the highway, accelerated, no major noise aside from what was previously diagnosed by the dealer as a wheel bearing starting to make noise (more on this later). Acceleration is fairly quiet, but once slowing down in gear, any gear, that knocking/horse trotting noise came on. When I push in the clutch, its still audible, just not as loud. Probably something to do with torque application.

I get it home, all the time testing it under load, in gear, out of gear and coasting, etc. Same noise the entire time.

Car gets pulled into the garage. I raise the passenger side front wheel, which is where the noise seems to be coming from, and spin the wheel with the transmission in neutral. I hear the trotting noise- not as loud, but not quiet either. At this point I am glad it isn't rod knock.

First things first, I check for leaks at the joints and transmission. None at all. Check the dipstick, has clean fluid, no bad smells. Check for play in the wheel bearings, none. I start thinking this noise isn't the wheel bearing and was misdiagnosed at the dealer. Upon laying under the car while turning the passenger front wheel and listening, the noise isn't from the hub, its from where the front passenger axle meets the transmission.

Next, drop the passenger side, raise the drivers front and do the same. No noise.

Jack the car up in the front with both wheels off the ground thinking it could be a suspension load thing and spin either wheel. No noise, the wheels spin opposite direction of each other like they should. Turn the steering wheel tot he max on the left and right and spin the wheels at the point of maxing out, still no sound.

With the front wheels still off the ground, I set a breaker bar on a lug nut and "lock" the passenger wheel from spinning. I spin the drivers wheel, no noise. Repeat with locking the drivers wheel the same way, I get the trotting noise.

I'm at a loss for what the problem could be. I'm thinking that the races that hold the ball bearings in place in the CV axle could have broken and the balls are clacking/rubbing against each other or that the c clip is broken and the axle is separated from the shaft and is making noise based on application of torque.

I found these threads, but neither are 100% whats happening in my case, but could be plausible.

http://legacygt.com/forums/showthread.php/center-differential-fail-199078.html?t=199078&highlight=noise+transmission+axle

http://legacygt.com/forums/showthread.php/nasty-clunk-up-front-219725.html?t=219725&highlight=noise+transmission+axle

Can anyone help me out?

If it is the CV axle, I'm reading that its best to go OEM, is that pretty true?

Also note that I do not beat on this car, its my wintertime/rainy day driver. The most abuse it sees is snow-nuts in the ski hill parking lot.

Unfortunately I can't help with the issue you are having. But what I can say is that with the MT legacies, I've read a lot of good reviews about the autozone 7336 remanufactured axles. I've read AT's should stick with OEM since aftermarket axles can cause vibration in drive, but MT's are good with aftermarket.

I replaced my two front axles with remanufactured 7336's last year, and they seem to work just fine. I think the ball bearings in the reman 7336's are hollow, versus solid with oem cv axles, because the remans do make a little bit more noise than my oem cv axles did. The noise isn't bad though, I can only hear it at certain times when the radio is off. You can hear it from around 9-16 seconds, 19-21 seconds, and 26-27 seconds in the video link below.

https://youtu.be/LxPb92p-MJA

Thank you for clarifying the aftermarket axle questions.

It was tough to hear that sound, but it was very clear to me at the 26 second mark. It sounds very similar to mine, just more muted.