Bad front axle or transmission problem? I need some input please

[lookaught]

My car has yet another issue... seems like there have been a lot recently.

A few days ago I was cruising home and heard a little 'pop' of sorts while rolling off a main road onto a side street near my house. I initially thought I hit something while changing lanes but then... as I was accelerating up a pretty sharp right hand bend about 500 feet later, I started to get some serious vibration and rumbling but only when on the throttle (1/2 throttle or more I'd guess). Since I was already home, and it was late, I parked it and decided to figure out the problem the next day.

So the next day I get it, drive around... no noises. Nothing. I could boose up to 15+ psi and I heard no abnormal sounds.

Fast forward to Saturday night, I'm on the turnpike driving to the mountains and sure enough, it's back. I've isolated the noise to only while accelerating, and pretty much only while making right hand turns. It sounds like it's coming from the front left, but it's hard to tell for sure. Vibration that I can feel easily through the pedals, and a pretty loud noise.

Ok so to me that sounds like an inner CV problem. Turning right, the power tire is the outside left so the power goes to that axle, and I get a noise, correct? In a strait line or turning left the power tire is the front right... so no noise.

I jacked up the car and pulled on some things and didnt notice any slop that seemed out of the ordinary... but here is the question: with the car in neutral and three wheels on the ground (front left in the air) I can turn the axle with my hands and the transmission makes some clanking noises as it turns... is this normal? Is it possible that something broke inside the trans that would result in the symptoms I described? Shifting feels fine, no abnormalities felt through the clutch pedal or shifter. I have to pull the transmission this weekend to replace my clutch, is there any way I can test it? I think I'm going to buy two Advance Auto axles and will replace them, and plan to take apart the inner CV to take a peek at the wear. The boots are all in great shape.

Thanks for any tips, sorry for the long post. This damn car is really annoying me recently.

[dirtybrd]

That's odd. I'm at a little confused on this one.

[Sales@RAI]

wheel bearing. Are you sure the sound is coming from the trans and not the hub?

[dirtybrd]

That wouldn't explain the pop and vib. and them being gone now.

[lookaught]

wheel bearing. Are you sure the sound is coming from the trans and not the hub?

The car rolls butter smooth both strait and through turns in both directions as long as Im coasting, so I don't think its a bearing. This was a pretty acute noise.

Chris it's not gone now, it had disappeared but perhaps that was because I was just not accelerating hard through right hand bends and I didnt notice it... It's present all the time now.

[dirtybrd]

So it shaking under hard accel?

[AudiDriver1986]

my car was doing the exact same thing... well first off it started with a groan when turning right.. next on my way to Alabama from Maryland almost uncontrollable vibrations when accelerating only.. and now i get a click sound when i accelerate, or when i turn to the right.. just a sharp like click sound.. i have not had it fixed yet, but my mechanic told me that it was the cv boot... hope this helps you

[dirtybrd]

Clicking when turning is the outer CV joint, vibration under accel only is and inner CV joint.

[lookaught]

Not just hard acceleration, even moderate. Light acceleration is no problem. That's why I think it's an issue when the diff is putting power to that tire: Medium to hard acceleration when going strait (though sometimes I hear nothing when going strait) and when turning right and the left side is on the outside of the turn.

[dirtybrd]

If you lift the drivers side and spin the wheel, will it make that same noise as the left side? If it doesn't, I'm thinking axle. If the diff had a problem, it would make the noise by spinning either side.

[lookaught]

my car was doing the exact same thing... well first off it started with a groan when turning right.. next on my way to Alabama from Maryland almost uncontrollable vibrations when accelerating only.. and now i get a click sound when i accelerate, or when i turn to the right.. just a sharp like click sound.. i have not had it fixed yet, but my mechanic told me that it was the cv boot... hope this helps you

I actually did get very, very quiet groaning when turning very, very slow speed right hand sharp turns (such as at the end of my alley behind my house), but thought that was a PS issue. Perhaps it was a precursor to this current problem. No clunks or vibrations though, just a very deep, quiet groan.


I think the logical thing do would be to pull the axle and inspect the CVs after I knock them apart. FOr $72, I kind of would rather just replace the axle and see if the noise goes away rather than take apart the CV and get nastiness all over. The bigger concern is pulling the trans, replacing the clutch and alxles, then putting it back together to find out it's a problem with the center diff or trans.

PITA!

Thanks for the input thus far guys!

[lookaught]

If you lift the drivers side and spin the wheel, will it make that same noise as the left side? If it doesn't, I'm thinking axle. If the diff had a problem, it would make the noise by spinning either side.

I think we are confusing sides here... I consider the left side to be the drivers side, and it is the only side that I inspected. The noises that I hear when I spin the drivers side front axle with the trans in neutral and the other three wheels on the ground are definitely coming from the transmission, but they could just be normal noises from the gears. The noise the trans makes sounds nothing like the clunking/vibrating/rumbling that the car makes while driving and turning right... but then again, I'm spinning it by hand at about 10rpm, not driving speed.

[dirtybrd]

I just screwed up what I was typing. I haven't heard of any diffs failing but alot of axles have.

[bl0wn3ur0]

I have been having the same issue since I changed my exhaust. I get a grinding/rubbing noise if I'm making a left turn, I thought the exhaust was rubbing but sometimes I get a loud noise with a lot of vibration when accelerating. It seems to only happen when its raining(weird I know) but I have no idea what it is.

[lookaught]

Well I bought a used left front axle from a local yard for $55 shipped, and once I get a new stretch bolt from the stealership I'll swap it out and see what happens...

The Advance Auto axles were out of stock both locally at the distributor. Dammit. I wasnt going to spend $$$ at raxles until I was sure it is the problem.

I will update this weekend. I'm getting the part on Thursday.

[3vom]

Any update? I have almost the same issue...

[diagnosticator]

My car has yet another issue... seems like there have been a lot recently.

A few days ago I was cruising home and heard a little 'pop' of sorts while rolling off a main road onto a side street near my house. I initially thought I hit something while changing lanes but then... as I was accelerating up a pretty sharp right hand bend about 500 feet later, I started to get some serious vibration and rumbling but only when on the throttle (1/2 throttle or more I'd guess). Since I was already home, and it was late, I parked it and decided to figure out the problem the next day.

So the next day I get it, drive around... no noises. Nothing. I could boose up to 15+ psi and I heard no abnormal sounds.

Fast forward to Saturday night, I'm on the turnpike driving to the mountains and sure enough, it's back. I've isolated the noise to only while accelerating, and pretty much only while making right hand turns. It sounds like it's coming from the front left, but it's hard to tell for sure. Vibration that I can feel easily through the pedals, and a pretty loud noise.

OK so to me that sounds like an inner CV problem. Turning right, the power tire is the outside left so the power goes to that axle, and I get a noise, correct? In a strait line or turning left the power tire is the front right... so no noise.

I jacked up the car and pulled on some things and didnt notice any slop that seemed out of the ordinary... but here is the question: with the car in neutral and three wheels on the ground (front left in the air) I can turn the axle with my hands and the transmission makes some clanking noises as it turns... is this normal? Is it possible that something broke inside the trans that would result in the symptoms I described? Shifting feels fine, no abnormalities felt through the clutch pedal or shifter. I have to pull the transmission this weekend to replace my clutch, is there any way I can test it? I think I'm going to buy two Advance Auto axles and will replace them, and plan to take apart the inner CV to take a peek at the wear. The boots are all in great shape.

Thanks for any tips, sorry for the long post. This damn car is really annoying me recently.

First, on dry pavement with an "open" diff, going straight, the power flow to the two sides is equal, and the speed of the internal parts is the same,and while turning, the power flow is to the outside wheel. This is because the two sides cover a different distance during the turn, and the outside wheel covers more distance than the inside wheel through the turn. Remember that open diffs send power to the wheel that is rotating the fastest, on ice that is the spinning wheel. The diff parts that are loaded the most during either a left or right hand turn, if damaged, will cause a loss of mechanical drive in an erratic fashion as the diff gears with the most load rotate during differentiation. Since the physical damage in each case is unique, there is no single symptom of wrecked diff gears except as manifest by the rough vibrations and noises of the damaged diff parts rotating with the load on individual parts varying by the direction of the steering and steering angle, and the directional loading of the internal diff parts while the diff is loaded. The diff doesn't act up when traveling straight, because the axles and the internal diff parts driving the axle shafts are equally loaded and are rotating at the same speed. You can turn the wheel that is off the ground because of the open diff in front, and the torsen center diff with the trans in neutral.

[lookaught]

Any update? I have almost the same issue...

It was the inside CV of the drivers side axle, as expected.

I tried to buy one of the chinese axles but they were out of stock, then bought a used axle from a semi-local yard. The first one they sent to me was for a B5, the second one had damaged threads where the axle bolt threads in... the retard that removed it punched it out of the hub with a 1/2" extension and there were four little corner marks marring the threads

So I did what I should have done to start with. I called Marty at raxles.com and two days later the car was together and working perfectly. He said on the phone that the B6 fronts use a "bucket" design for the inner CV, which is nice because it's not messy like the B5 normal CV design, but they wear out much, much faster, especially with a lowered car. My car isn't lowered but that axle did have 98,000 miles so I guess it just failed.

Regardless, $225 for a new axle and I paid for 2 day air shipping so $240 and it was fixed.

and a bigto Marty at raxles. He is the man!

[lookaught]

First, on dry pavement with an "open" diff, going straight, the power flow to the two sides is equal, and the speed of the internal parts is the same,and while turning, the power flow is to the outside wheel. This is because the two sides cover a different distance during the turn, and the outside wheel covers more distance than the inside wheel through the turn. Remember that open diffs send power to the wheel that is rotating the fastest, on ice that is the spinning wheel. The diff parts that are loaded the most during either a left or right hand turn, if damaged, will cause a loss of mechanical drive in an erratic fashion as the diff gears with the most load rotate during differentiation. Since the physical damage in each case is unique, there is no single symptom of wrecked diff gears except as manifest by the rough vibrations and noises of the damaged diff parts rotating with the load on individual parts varying by the direction of the steering and steering angle, and the directional loading of the internal diff parts while the diff is loaded. The diff doesn't act up when traveling straight, because the axles and the internal diff parts driving the axle shafts are equally loaded and are rotating at the same speed. You can turn the wheel that is off the ground because of the open diff in front, and the torsen center diff with the trans in neutral.

Thanks for the explanation! I suppose for most of us process of elimination would be the only way to diagnose a diff problem... meaning replace the axles and if it doesn't fix the problem, then replace the trans with a used one as it's cheaper than taking one apart.

Luckily in my case the axle fixed it.

[diagnosticator]

Thanks for the explanation! I suppose for most of us process of elimination would be the only way to diagnose a diff problem... meaning replace the axles and if it doesn't fix the problem, then replace the trans with a used one as it's cheaper than taking one apart.

Luckily in my case the axle fixed it.

That is good news concerning your fix! Much easier and cheaper than fixing a diff internal to the trans! Thanks for the update. BTW, Providence was looking out for you regarding the Chinese axle, regardless of the fit up of the part, Chinese parts on an Audi is just offensive IMO. Especially "aftermarket" parts. (Exception: Audis made in China...)

[lookaught]

Well I actually don't mind paying more for a raxle, the reason for the Chinese axle was that I didn't know if the axle was definitely the problem, and didn't want to spend $150 more to fix nothing.

But yes, thank god it was an easy fix!

[diagnosticator]

Well I actually don't mind paying more for a raxle, the reason for the Chinese axle was that I didn't know if the axle was definitely the problem, and didn't want to spend $150 more to fix nothing.

But yes, thank god it was an easy fix!