Check this guy out...

[brus brother]

OK, I've been lurking in the shadows and watching this thread's goings ons.

Sir from Oklahoma, your final bow contained some startling information. That many defective reman axles seems problematic to this casual observer.

Having to sort through 4 defective axles to find one that you found acceptable is a very failing grade of 20/100. The less obvious defects (maybe even the one you finally installed) will take time to evidence themselves and hopefully the naive customer will have forgotten who did the last work.

When my inner boot tore, I started shopping various suppliers and learned that some rebuilders use new parts and others just regrind. The price was reflective of the caliber of the rebuild.

Having been forewarned of the vagueries of the aftermarket axles, for this very reason and with the help of this board, I opened, cleaned and rebooted my Subie original axle shortly after I became aware that it was torn.

Thanks again to the board for sharing observations and hopefully Sir Okie will continue to drop in and lend some wisdom.

[WAWalker]

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.

You answered your own question below. Didn't you? You "inspected" 5 axles, only one was "acceptable" to you. If quality is all the same just packaging is different, how does this happen?

 

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.

 

So you have seen the inside of enough NEW OE Mitsubishi CV joints to know what kind of finish Mitsubishi requires? Or you have the specs that Mitsubishi provided their axle manufactures? Or your just really really good?

 

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.

 

Five minutes total for inspecting axles and what, 2-3 days of down time for an axle replacement= Inconvenience for a customer, and loss of profit.

 

Your not a working tech these days are you?

 

I've installed many axles that didn't "feel quit right" that have turned out to be just fine. That could just be that I'm not competent enough to "feel" the quality of an axle though.

[WoodsWagon]

As someone who has a car in the family experiencing this problem, and as a working tech, I feel compelled to offer a clear and concise explanation.

 

Part one:

All 4cyl engines vibrate at idle. Some vibrate worse than others, like my mom's outback, which has extreemly bad piston slap and a compression reduction due to it on one cyl. When the transmission is in park or neutral, or the clutch is pushed in, the engine transmission unit vibrates by its self on the rubber mounts. This is because no torque is being transfered out of the unit.

 

Part two:

The length of the axle is not the problem here. If it was bottoming in the joint, the axle would destroy it's self or the transmission as soon as the suspension compressed. The problem is the tolerances in the Constant Velocity joints. In a perfect world, there would be no rotational backlash between the inner DOJ cup and the outer hub splines. When you are buying a $60 part made by low-wage workers, you are not buying a perfect world. This excess backlash means that the inner cup can rotate back and forth without turning the wheel hub.

 

Part three:

With the tranny in drive, there is a load being transmitted from the ilding engine, through the fluid coupling, and out to the differential. This is not smooth torque, due to the low RPM's and torque impulses being generated by the firing cyl's. The subaru torque converters are fairly "tight" as in they transmit a fair portion of the engine's torque at low engine speeds. So the variations in engine torque are sent right through to the transmission and out to the differential stub axles.

 

Conclusion:

The torque variations present on the stationary differential stub axles try to turn the halfshafts with a changing amount of force. The outer end of the halfshafts is held stationary by the brakes. As the torque varies on the inner DOJ cup, it experiences slight rotational movement With greater tolerances in the CV joints, the rotational movment will become greater. This creates a hammering action on the joints. This hammering is transmitted to the wheel hub assembly and is felt through the steering linkage and the suspension.

 

Solution:

Replace the axle with one that was manufactured to much closer tolerances.

OR

Replace the torque converter with a high-stall performace version. This converter will be much less efficient at transmitting toque at low RPM's, and so the torque variations experienced by the transmission at idle will be greatly reduced.

 

 

I guess that wasn't as concise as I hoped, but I think it covers most of the angles of the problem.

 

Okie440, realize that calling a large group of people delusional morons who can't install piston rings is a poor way of justifying your lack of understanding. You are not the only technical expert on the internet, and the reality that someone who may know more than you is out there always exists. Thumping your fist on the virtual table and disparaging peole who offer an alternative explanation doesn't get anyone anywhere.

So I hope you stuck around long enough to read my explanation.

[WAWalker]

That is probably the clearest explanation so far.

 

Not the first to say basically the same thing...................but I don't think it matters how many times it is repeated...............If someone doesn't want to be "wrong" they won't (in their mind).

 

Entertaining none the less.

[keltik]

I think this issue is illustrated brilliantly on my 2 stroke dirt bike. It vibrates a heckuva lot more in gear compared to in neutral.

 

The crappy 2 stroke idle isnt a problem on its own but when you have that lumpy idle transmitted through the gearbox and chain - the bike shakes (the clutch drags a wee bit - analogous to a torque converter). The wheels arent moving - the gears in the box arent moving much and the chain isnt going anywhere but the bike vibrates more.

 

I havnt had a bad axle in a car cause this, but seeing it happen on my bike has made me much more aware of the possibility of it occuring.

 

Sorry for going off on a tangent here but it seemed quite related lol.