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Pattern failures are a very real thing.

If they were not these types of message boards would not thrive as they do.

There would be not IATN, Idenaifix, TSB's., etc.

 

When an OE axle is replaced (simply due to a torn boot) with an aftermarket unit of questionable quality...............now all of a sudden there is an obvious annoying vibration that wasn't there before.......................then that axle is replaced with a high quality aftermarket or OEM replacement axle, and the vibration is gone.............................

 

Who is going to take the time or spend the money to disassemble the two axles to see what is different.

 

Not me. I personally, as a shop owner and mechanic specializing in Subaru repair, will switch axle suppliers. There are just some things I don't need a technical explanation for.

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Who is going to take the time or spend the money to disassemble the two axles to see what is different.

 

 

I'm bored. If someone wants to send me one brand new OX axle and an aftermarket i'll take them apart :)

 

(like thats going to happen)

 

nipper

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Seems perfectly reasonable to me that a longer aftermarket axle could be transmitting engine vibrations to the body at idle.

 

As for my qualifications - none relate to Subaru fixing in any way and i sell fridges (and tv's) for a living. But at the end of the day - ive held a Subaru axle in my hand and seen the hole it came from. That makes me reasonably qualified to solve the problem.

 

I think its a bit unfortunate a flame war was started instead of just ignoring an irritating post.

 

Finally - as im having a french day "Vive le USMB". It kicks rump roast :headbang:

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I will maintain to you that an auto transmission in DRIVE, sitting stationary at a traffic light will not vibrate due to a half-shaft. It may vibrate for any one of a hundred reasons but the axle shaft is not one of them. From the wheel lugs clean through the entire differential, NOTHING is moving when the vehicle is at an idle.

 

 

Not true. the only thing held stationary is the wheels. Torque is still being transmitted to the axles, through the differnetial.

 

Follow me here, it' gonna get murky.

 

So, let's say the drives side axle is replaced with a crummy one. One that has a TINY bit of play in the DOJ(inboard) joint. When torque is trnasmitted through it, it rotate the cup slightly, by the amount of the slop, around the axle, which is held stationary by the brake.

 

So what happens on the other side? Well, it's an open diff. A small rotation in one direction for the drivers side, means a small amount of opposing torque to the pasenger side.

 

But the passenger side has no play, and is held still by the brakes as well. So the torque is returned to the drivers side. It now rotates the cup back the other way(because of the slop or play) again, reversing the torque back to the passenger side, which cannot move, so back to the drivers side.

 

I propose that it is this "bouncing" of torque through the differential that causes the shaking. Exacerbated by the fact that the engine already has a tendency to wobble side to side. Excactly equal length shafts also set up the vibration, as each has equal properties, and potential to affect the other.

 

I think in most FWD cars, this doesn't happen becasue of unequal length shafts, with transverse mounted engines. Tranverse engines don't want to wobble "side to side", they rock fore and aft. Plus the unequal shafts have unequal ability to affect the other.

 

Harmonics is a tricky science. Things that where thought impossible crashed alot of airplanes before they started harmonics testing. And who can forget the Tacoma Narrows bridge flopping like a rubber band in the wind.

 

OK4450, I fully understand you're thinking here. Nothing is rotating=no cause for vibration. I get it. That is very standard and mostly correct thinking. Intuitive Mechanic stuff.

 

But it is just not that cut and dry. There is ALOT of evidence that this DOES happen. It is peculiar to Subaru, but then again, so is the symetrical FWD layout.

 

 

Oh, BTW, I operate my own Independant Subaru shop.

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Not true. the only thing held stationary is the wheels. Torque is still being transmitted to the axles, through the differnetial.

 

Follow me here, it' gonna get murky.

 

So, let's say the drives side axle is replaced with a crummy one. One that has a TINY bit of play in the DOJ(inboard) joint. When torque is trnasmitted through it, it rotate the cup slightly, by the amount of the slop, around the axle, which is held stationary by the brake.

 

So what happens on the other side? Well, it's an open diff. A small rotation in one direction for the drivers side, means a small amount of opposing torque to the pasenger side.

 

But the passenger side has no play, and is held still by the brakes as well. So the torque is returned to the drivers side. It now rotates the cup back the other way(because of the slop or play) again, reversing the torque back to the passenger side, which cannot move, so back to the drivers side.

 

I propose that it is this "bouncing" of torque through the differential that causes the shaking. Exacerbated by the fact that the engine already has a tendency to wobble side to side. Excactly equal length shafts also set up the vibration, as each has equal properties, and potential to affect the other.

 

I think in most FWD cars, this doesn't happen becasue of unequal length shafts, with transverse mounted engines. Tranverse engines don't want to wobble "side to side", they rock fore and aft. Plus the unequal shafts have unequal ability to affect the other.

 

Harmonics is a tricky science. Things that where thought impossible crashed alot of airplanes before they started harmonics testing. And who can forget the Tacoma Narrows bridge flopping like a rubber band in the wind.

 

OK4450, I fully understand you're thinking here. Nothing is rotating=no cause for vibration. I get it. That is very standard and mostly correct thinking. Intuitive Mechanic stuff.

 

But it is just not that cut and dry. There is ALOT of evidence that this DOES happen. It is peculiar to Subaru, but then again, so is the symetrical FWD layout.

 

 

Oh, BTW, I operate my own Independant Subaru shop.

 

 

Those are excellent points. Additionally, let's remember that the ENTIRE car (spring mounted on the suspension) is vibrating to an extent when it is sitting at idle. There are cars which use harmonic dampers mounted in the front bumpers, tuned to a particular resonant frequency to oppose 4-cylinder induced idle speed resonances. In the pre-airbag era, some cars had masses mounted under the steering weel pad to damp out vibration, etc. etc. Almost any part which is mounted to the car can potentially improve or worsen idle vibrations, let alone a part of the drivetrain itself, such as a half-shaft assembly.

 

Nathan

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I read the whole thing...

At first, I thought, what!? That 'mechanic' installed the belt a tooth off. Then I remembered the comment about "foil hats"; I found that they are very easy to make and- the one I made actually works! As I put the hat on, I instantly began thinking more clearly.

 

But seriously, the explination of everything being motionless is only valid if the parts all have tight tolerances. The torque converter does see engine load at idle and it transmits this load through the axles to the wheels. This is not a constant, smooth torque because we are talking about H4 engine, not Buggatti V16's. Our little engines like to shudder a little bit at idle with a little load on them. It's normal. But if you open up the clearances on one of those axles, you change the stability of that 'stationary' part and this may be enough to get the whole thing shakin'. Harmonics can do some pretty amazing things. Read up on that little harmonic device that Tesla made that caused a multi-level building to shudder like an earthquake. The device fit in his pocket.

 

This is just one more reason I do all of my work myself. If it was my car with this issue, I would have thrown a fit over the 'mechanic' goofing with the idle screw. Then I would distrust his abilities. If I had changed the axle and seen this vibration first-hand, I would scratch my head and I would be sure I must have knocked something else loose in the process of changine the axle.

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i agree what GLOYALE says, since i just read the rest of this topic AFTER posting my reply at the NPR board:

 

spacer.gifRe: Update - 2003 Subaru timing belt replacement concerns

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rating_830888.className = 'rated' + Math.round(0.0); //alert(Math.round(0.0));

 

in reply to the last thread, when the car is stopped in ger, with the brake on, there is still torque going thru the axle. and with the equal lenght of the axles the torque is going to go thru to the least path of resistance, being any SLOP in the doj or cv of the defective axle. for you who doubts this maybe it wouldnt prevail on a dideways mount engine with UNEQUAL lenght axles. and yes i am from USMB.

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First off, I am going to apologize here for something. I should not have used the words delusional and moron. It was done in moments of frustration, but in retrospect frustration is to be expected when you're trying to put a mechanical explanation across to someone who is not mechanically minded. I've only gone through the same thing with my wife a hundred times when trying to explain something vehicle related to her.

 

If anyone follows my posts on CT they would know that I don't normally resort to this kind of thing, so I offer a sincere apology right now.

 

As to comments about my expertise, or even the profile "egotism" that is mentioned, that is not true. If any of you knew me personally you would see that that does not apply to me in the least. I AM confident in my mechanic abilities (about 35 years plus) and if the ego part is related to the "multi-faceted" part on my profile that is not meant as an ego trip, period. I do have the ability do many other things outside of the auto world in spare time including repair of home A/C units, repair and installation of garage doors/operators (from small residential to 100 foot long commercial), etc, etc. I can even machine my own brake rotors and crankshaft hubs from bare metal blocks if I choose to.

The fact I stated on my profile page a few of my outside activities, if you want to call them that, is not an indication of egotism. It's simply to give whomever might read that page a general guideline about the guy behind it. Personally, I'm surprised that anyone ever reads any of them.

 

In spite of the bashing I've gotten from Mr. Hewitt, and others, I'm not upset with him at all. JMHO, but I think he's being yanked a little bit by his mechanic. Tampering with a screw that should not be tampered with, by his own admission the mechanic "was confused", and the playing around with the throttle plate screw looks bad to me.

I could go into a number of paragraphs explaining to Mr. Hewitt why he could be getting yanked but he is convinced the axle was the problem so why bother. Professional mechanics should know exactly what I'm talking about here.

The problem was there, it's gone now, so ergo it has to have been the axle. Maybe, maybe not IMHO.

 

A couple of closing points here. It has been mentioned about axle length, the strain of the engine pulling on the axle, etc. and I think a point is being seriously missed here.

The outer joint is fixed; there is no linear movement in it. However, on the inner DOJ the entire inner race/balls slide back and forth in the ball grooves much like bowling balls rolling in the gutters. There is more than enough movement here to offset any of this perceived strain. A higher than normal idle will cause some strain but this falls back onto the idle adjustment situation again.

 

The last point is that on the way home yesterday I stopped by a transmisssion shop a friend of mine owns. He has about 40 years in on transmissions, half-shafts, etc., is an "expert's expert" to put it one way, and when I posed this question to him he also thought the problem was elsewhere.

 

So, again I apologize for getting out of line with the name calling.

I will not retract any remarks about the cause and effect of the mechanical problem involved here because I've been involved with too many Subaru half-shaft rebuilds, replacements, and differential repairs to buy into it.

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Im sure theres a line where "trying to prove a point" turns into "bow down to me goddammit! im always right". I fear it may be getting close.

 

Personally i wouldve stayed over on the other side of the internet and let such a minor complaint go. Mr Hewitts problem is resolved and after your remarks regarding the USMB (being a bunch of unqualified try-hards) it seems quite foolish to expect an understanding audience here. So why are we still arguing about this?

 

Edit: And to clarify my position, creating a thread with the intension of ridiculing another poster is a rather narrow-minded solution. How are we all going to feel if the vibration comes back in a week....

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As a member of both board sites I have been following this issue on both sides and didn't want to get involved with the issue, especially since I didn't have much to contribute. I have now decided to make some comments of my own on this.

 

I have read a lot of OK4450's replies to folks on the CarTalk site and will say that he always has very good advice for people on the problems they need help with. In regards to the comments you made about the members here OK4450, I had hoped you really didn't mean them and your previous posting proves you didn't. There are a lot of good techs here that know which end is up, as there are on the CarTalk site. With your good background in Subarus and other vehicles my hope is you will stick around here and help others as you have at the other site. We all have the same goal in mind in helping folks with their vehicle problems. So, since you have already signed up why not stick around. I think you may enjoy it.

 

As far as the axle shaft issue is concerned; while I really like to know what the root of any problem is, I am content with knowing that if a certain part has helped others fix the issue or caused a change for the good somehow, then that is good enough for me.

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[Touchy-feely stuff up top here, but I do have a couple mechanical queries near the bottom...]

 

I should apologize as well. As keltik very rightly pointed out, I should never have started a thread here focused on ok4450's comments on another board. Very poor on my part. I did hope that it would generate a bit more discussion on what exactly causes this vibration (via countering ok4450), and at least that part of my purpose was realized. It's an interesting mechanical thing going on here, even if I have no first-hand experience "under the hood" with it. (Also, if that vibration comes back, you're right - I'll feel real bad, for two reasons.)

 

I also should (and do) apologize to ok4450, as I trust the assessment of others that he's helpful and a good addition to the CarTalk board (and perhaps this one in less heated threads).

 

That said, ok4450, when you say things like:

... in retrospect frustration is to be expected when you're trying to put a mechanical explanation across to someone who is not mechanically minded.

... the not-so-shrouded criticism is still obvious. It's similar to my comment about your profile, which was unnecessary and uncool. Sorry. Overall though, I don't think I gave a "bashing" of any type. I just re-read my CT posts and I don't see any bashing in there. I think you got hot about this because you knew more than me (admitted) and couldn't stand me not agreeing with you.

 

Now, to the mechanical stuff...

 

Right up front, this mechanic is not yanking me. He's a valued mechanic in the area and has across the board 5 stars in the Mechanix files at CT. He's become a friend and values my business. It would do him no good to yank me.

 

* The throttle plate screw (or idle screw, whatever you want to call it):

-- My mechanic apologized for all that and I GET IT that that was bad. He said the car wouldn't let him adjust it more than a few thousandths (of an inch? [not sure what measurement he meant]) so it wasn't a route to a real fix. He did move it a bit and now he moved it back. My question is: If that's such a bad move, what does it do to engine performance? Other than the vibration, we took a 1000 mile road trip with that adjustment and got great gas mileage. ??

 

* I also have not heard any consensus about whether a timing belt being off a tooth could be the problem. Many yeses, many nos... Recalling that this is a 2003 Outback with the 4-cyl and auto trans, CAN the thing perform fine (other than a vibration at idle) with that belt off a tooth?

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I think the throttle body adjustment is a calibrated set point for the ECU to go by. The set screw depth determines how much air gets though I think. I am not real familiar with this area but I think this is correct.

 

Since you had excellent gas mileage on the trip I would suspect everything is ok with the engine.

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1. Aftermarket axles are cheaply made. We know this.

 

2. A HARD connection between the engine and the supension/body can transfer vibration. That's why engine/tranny mounts are made of rubber, not cast iron.

 

3. If the aftermarket axle's DOJ were to bind slightly due to poor machineing, poor grease distribution, or anything else, it *could* create a HARD connection between the tranny and the suspension. Thus transfering vibration when it would otherwise be isolated by the engine and transaxle mounts.

 

What's so hard to understand about that? The ability of the axle to absorb vibration transfered through the DOJ lies in the ability of the joint to slide in and out freely. If that were comprimised by a poorly made axle then it definately would transfer lateral vibration through to the knuckle and this would be felt inside the cabin.

 

End of story.

 

BTW - I'm a mechanic too, and I DON'T have 35 years experience. But I understand - I work with a lot of people that do, and I have to correct them all the time. It's because I actually READ and comprehend the manuals. I'm constantly having to pull down manuals and look stuff up to correct folks.

 

GD

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I think people got off on the wrong foot here. This is just my opinion: if everyone on this board was a knowledgeable, experienced mechanic they probably wouldn't be asking for help in the first place.

 

ok4450, welcome to the board. Please understand that getting heated and arguing with people about who's right or wrong may discourage others from asking for help and trying to help. With that aside I hope you will stick around and offer your knowledge to others, after all, it's a team effort and there's strength in numbers.

 

dhewitt, welcome to the board. Your recruiting tactics are brilliant!:lol:

I'm also glad to hear your that vehicle is fixed, I hope it treats you well.

 

I hope we can all get along and enjoy this board. This is just my 2 cents worth.

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To start off tonight, I will apologize again to Mr. Hewitt in regards to comments about trying to explain something technically to someone not mechanically inclined. Mr. Hewitt, I assure you there was not meant to be any subtle criticism or dig behind those remarks but I apologize for wording it poorly.

A couple of quick comments here.

 

One is in regards to OEM Subaru half-shafts and the so-called "aftermarket" shafts. Reman shafts are generally OEM Subaru shafts. The remans are simply rebuilt OEM ones. A couple of years ago I sold about 40-50 Subaru OEM shafts, along with a comparable number of OEM Subaru alternators/starters, to a reman facility as cores to get them out of my hair. These all wound up in your local parts houses and you may consider these "aftermarket".

Just an FYI here. Subaru does not manufacture their own half-shafts so technically an OEM shaft would be considered an "aftermarket". Subaru also does this with many other items on their cars; suspension parts, clutches, etc.

Every other car maker does the same thing.

An example might be TRW. TRW furnishes ball joints, tie rods, seat belts, air bags, brakes, etc. for many car makers; Ford, Chrysler, Toyota, Nissan, GM, etc, etc. along with many parts house operations. The only difference is the packaging. I don't remember what or how much TRW supplies Subaru but you get the picture.

 

The last comment about half-shafts. Half-shafts, mechanically speaking, are what I would consider grade school level mechanical repairs. Easy to install, easy to disassemble, and even easier to inspect both visually and by feel while the shaft is on the bench.

 

As I stated, I don't buy into this for one minute, but for the sake of argument here let's assume this vibration problem was caused by a half-shaft problem.

This means that any half decent technician should be able to take that defective shaft while on the bench and find the problem within 2-3 minutes.

If the shaft has a problem that causes a vibration then it should be very apparent with a quick physical while it's on the table.

 

Granted, there are some areas (especially electrics/electronics) where things are not always black and white but a half-shaft fault should be easy to discover if one exists. JMHO, but a mechanic has a responsibility to the car owner to be able to explain WHY the problem occurred and show them if at all possible.

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I'm going to take issue with some of this....

 

One is in regards to OEM Subaru half-shafts and the so-called "aftermarket" shafts. Re-man shafts are generally OEM Subaru shafts. The re mans are simply rebuilt OEM ones.....Just an FYI here. Subaru does not manufacture their own half-shafts so technically an OEM shaft would be considered an "aftermarket". Subaru also does this with many other items on their cars; suspension parts, clutches, etc.

Every other car maker does the same thing.

 

You are contradicting yourself. "OEM" stands for "Original Equipment Manufacturer". This means that the component was made by the SAME company that made them for the factory. It's all there in the acronym - you aren't telling us anything we don't already know. I have a few points of my own you should take note of:

 

1. NOT all remans are OEM shafts. There are other companies that make Subaru half shafts. GCK comes to mind off the top of my head. They are NOT an OEM, and their shafts could easily be in the reman world. They are by no means alone.

 

2. Just being an OEM shaft has been re-manned means NOTHING. Did they replace the joints? What brand did they use? Or did they weld up the worn spots on the old joints and grind them? What kind of boots are they using? Quality or not? The only part of the axle that isn't a wear item is the SHAFT itself - but it's got no moving parts - it's just a machined rod.

 

3. Different part numbers get all mixed together. For example the EA81's use two different front shafts for 4WD and 2WD. Shaft, and joint diameter is different. But they are 100% interchangeable. The remanufacturers know this and just lump them all together. So it's a crap shoot as to what you get when you open the box. This can be a problem for a lot of us that require the heavier duty 4WD axles but can't guarantee we will get them through these builders.

 

 

The last comment about half-shafts. Half-shafts, mechanically speaking, are what I would consider grade school level mechanical repairs. Easy to install, easy to disassemble, and even easier to inspect both visually and by feel while the shaft is on the bench.

 

Well - that's not entirely clear cut for Subaru's at least. I've had experience with axles that caused severe vibration but when disassembled they didn't look all that bad. It takes a very trained eye to inspect the components and correctly diagnose failures. There's a lot of folks that have reported bad axles right out of the box. The older Subaru's run their half shafts at a much higher angle than most cars on the road and CV's wear proportionally to their run angle, applied torque, and rotational speed.

 

As I stated, I don't buy into this for one minute, but for the sake of argument here let's assume this vibration problem was caused by a half-shaft problem.

This means that any half decent technician should be able to take that defective shaft while on the bench and find the problem within 2-3 minutes.

If the shaft has a problem that causes a vibration then it should be very apparent with a quick physical while it's on the table.

 

I'll agree to that to some extent. Someone properly trained in Subaru half shafts would probably see the problem. It would have to be a binding of the DOJ cup, and one would imagine you could feel this if you gave it a careful rotation while sliding the joint in and out of the cup. Depending on the boot, and how tight the thing is, it might be difficult to tell though. There's a grey area in there - at what point do you decide the axle is too tight and is transferring vibration to the cabin?

 

Granted, there are some areas (especially electrics/electronics) where things are not always black and white but a half-shaft fault should be easy to discover if one exists. JMHO, but a mechanic has a responsibility to the car owner to be able to explain WHY the problem occurred and show them if at all possible.

 

You would think so, but in practice the ancient art of Subaru half-shafts isn't always so simple. I've run into my share of strange effects from half shafts. Both from stuff that has failed, and from brand new parts that appear to cause second-order vibration from other parts of the vehicle that are worn out. Tranny mounts on EA series are a good example - some of the GCK shafts are so tight that they bounce the tranny all over the place if the mounts are squishy (as they very often are).

 

GD

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All very very good points GeneralDisorder.

 

One more thing I would add.

 

There are a lot of new axles (all new parts, made in China) being sold as "remaned" axles in the aftermarket now. Very unlikely that these parts are meeting OEM standards.

 

And.......ok4450..........In my shop if a customer wants an axle disassembled to find exactly what part of the axle is causing the problem, they would have to pay for the time to do so.

If the problem is a clicking CV or DOJ, a 2-3 minute diagnosis would be sufficient to tell them which joint is worn. But, as there are many parts that make up each joint it would take much more time to disassemble and measure to determine which parts were worn to the point of being "out of spec" enough to cause the noise.

If the axle is quiet, but is transferring vibration, I doubt 2-3 minutes would be enough time for anyone to come to a conclusion as to the cause of the problem.

If the problem is fixed by installing a quality axle, no one in their right mind is going to pay extra money for a tear down of the old axle.

JMHO, of course.

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I'm familiar with tight and binding joints, shaft length, and all of that.

In a vehicle moving 5 MPH I could definitely see a problem occurring because of any of that, but not on an inert, stationary joint.

 

In regards to the OEM parts, my point is that the company turning those halfshafts off the assembly line can very well be the same company producing them for the aftermarket. The only difference is the packaging.

The ball joints on my Ford are made by TRW and these same joints are sold by TRW to any one of a number of distributors who package them as their own for resale. The only difference may be that the aftermarket ones may or may not have the TRW logo on them.

 

One would think if this idle speed/halfshaft problem were related that one mechanically minded DIYer or pro tech would have figured out the cause and posted it on-line.

I for one would love to hear the technical explanation behind it.

I certainly understand the part about the customer not wanting to pay for this inspection but an inquisitive mechanic should be willing to spend 5 minutes of his own time in an effort to solve the puzzle. This is something I've done many times; it's not that painful to do.

 

One would also think word of this would have drifted back to Subaru of America and a Technical Service Bulletin would have been issued alerting their dealers of potential idle problems caused by bad shafts.

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From what I have read, what is being said is the "bad shaft" was not affecting the idle speed or quality, just making the car vibrate, and as the case, GD has a valid point. It stands to reason that if the shaft were too long and/ or binding/locking up in some way, then vibrations from the engine/transaxle assembly could be transmitted through the solid connection to the suspension created by the faulty axle, whether in motion or not, the engine still makes vibration as long as it is running. Basically it would have been bypassing the vibration insulating properties of the engine/tranny mounts. It is indeed possible, and I for one think it is time to let this one go and agree to disagree, if we cant agree that the axle *could* have been the problem.

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AAAAAaaAAAARGH!! But its not a bloody idle problem!!!!! This blokes talking about feeling abnormal vibrations in his steering wheel AT IDLE.

 

And We're saying this vibration could be transmitted to the steering control rods through a craply made axle.

 

It MIGHT be unlikely, but its even less likely that replacing the bad axle magically cured whatever unrelated problem caused this vibration.

 

Edit: Looks like beasty squeezed in a reply before me there. But YES! The axle is NOT vibrating. The MOTOR is. And we believe it is likely the axle was TRANSMITTING this vibration to the body at idle.

 

Apologies for sounding like an rump roast but this has gone on too long.

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Why is the comment about packaging not true? The Kenmore brand of appliance sold at Sears is made by Whirlpool or Frigidaire with the name tag and box it came in being the main difference.

 

What I would like to hear is a detailed explanation of this anomaly from a competent tech, car or parts manufacturer, automotive trade organization, reman facility, service bulletin, etc. from somebody, somewhere would clear things up for me.

Phrases such as "the problem is gone now so what else could it be", "too much of a coincidence", etc. are a bit shallow.

Regarding shaft length, which is not the cause IMHO, what kind of mechanic replaces a shaft without verifying the length against the old one before installation?

 

I stated in a previous post the shafts can easily be inspected while on a table. This is not rocket science and I can now present an example completed as of today.

The car in question is a Mitsubishi, which uses the tripod type joint on the inner and the Rzeppa joint (as does Subaru) on the outer.

 

A left side halfshaft was ordered and when inspected right out of the box on the parts counter I discovered it was bad within 60 seconds. They reorder not one, but two shafts - just in case.

So yesterday they came in and both were bad (one mildly, another near junk). Inspection took about 2 minutes on the parts counter.

 

Reorder 2 more shafts and they arrived today. Inspection showed one was acceptable (and is in the car now) and the other was defective as noted by a very subtle grind when moving the joint by hand. One of the 2 in the previous 2 joint order was also like this.

 

I asked the parts man if he minded if I removed the clamp and showed him the fault. No problem, and less than 60 seconds later the clamp is off, boot rolled back, and the fault is plain to see. The grooves for the balls are being ground with a coarse stone with no attempt to polish those grooves for smooth operation.

 

My point here is that it is entirely possible to inspect a half-shaft for a fault while spending very little time on it at all.

My guesstimate here on the inspection of 5 shafts, including popping a clamp and rolling back the boot, is about 5 minutes total.

I believe that a technician has an obligation to the car owner to be able to explain and show why a part is faulty or the problem exists.

This will be my last post here on this issue and thank you for your consideration of any points made.

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