So, how do you know if you've got a bad CV Joint?

[Guest soobee]

I'm on the cusp of a transmission replacement for my '95 Legacy--on the advice of a dealer service tech.

 

On a test drive he said he thought it sounded like the front differential. Then, later, while the car was on the lift he showed me that when he grabbed on to the drivers side CV Joint and it did have some play (the passenger side was rock solid). He said the bearings supporting the axle were bad. His advice was that the entire transmission be replaced because of the high milage on the car.

 

So anyway, having bought the "new" transmission and having seen the actual setup without the CV Joints attached it now seems improbable that those bearings would go bad...the axles are just too short...

 

It nails me after driving 8 hours and spending $$$ for a replacement that since he was cranking on the CV, it's entirely possible that all the play came from that...yeah?

 

What would be the indications of a bad CV Joint? I don't want to spend the money to put this thing in only to still have the same problem. What's more, I want to try and get my money back for this tranny (if I don't need it.)

[Guest roadtrip]

from my experiences with bad CVs, the definitive sound is a clunk or a thud when coming to a stop, just as you lose all forward momentum. another primary indication would be punctures or tears in the CV boot itself, allowing crud into the joint. probably not all the advice you were looking for, but it's a start.

[Guest nuburu2]

From my experience with CV joints, the joint makes a click-click-click-click-click, or thunk-thunk-thunk-thunk noise under power when turning, usually from a dead stop. They are pretty obviously bad when they go. If the output side of the trans is "sloppy" your service adviser is probably on the level.

 

Glenn O

[Guest PaganQWA]

Ok this guy told you to replace the tranny cuz a) your inner CV's are bad and it has alot of miles on it? If so he's an idiot Maybe I just read it wrong though...

 

Inner CV's will 'pop' or 'click' (usally several times) when you take off or are coming to a stop. Outer CV's will 'pop' or 'click' (again usally several times) when you take tight turns.

[Guest soobee]

So, say a constant buzz wouldn't be a good indicator of a bad CV, eh?

 

No thunk.

No click-click.

Just an ever present hum/buzz...

[Guest PaganQWA]

buzzing? No... CV's will give you a nice definat pop or click... like you should hear each individual pop/click. I spose if they were REAL bad they would do it all the time and at higher speeds it would be a buzz. Did you notice poping or clicking only on take off / slow down that has progressed to this buzzing or did the buzzing just creep out outa nowhere? Is your tranny full of fluid? (check while at running temp and engine is running) Does it buzz only in a driving gear or ALL the time?

[Guest soobee]

Well, based on the whole thud/click indication, I'd say the Subaru tech was correct and it's a bad differential.

 

Fluid's fine. (Just had a transmission service.) And the buzzing is all the time, predominately when the driver's side is experiencing a load (ie, turning right or driving while the road slopes [is graded] to the left.)

 

Okay, well, I feel better now.

 

Thanks.

.owen

[Guest Sam]

AWD? Automatic or Manual?

 

Definatly a clicking when acceleraiting or tight turns while acceleraiting, not a "thud when stopping"

 

Put the fuse in that dissables the AWD and see if your noise goes away. Or did you already replace the trans & the problem is fixed? A little fuzzy on the details.

[Guest soobee]

Trans isn't in. I was just paranoid that I'd taken a wrong step...from everyone's description it sounds like it's not the CV. I'm now more confident that it is the differential...I'll throw the new one in and cross my fingers.

[Guest Legacy777]

Ok, I can tell you with near certainty how to tell if the CV joints are going. I recently had mine regreased had an intermittant noise.

 

They make a click click noise when they are starting to go bad, and they usually make the noise when you turn. However if they are jsut starting to, you won't notice it.

 

Here's how to test it. You need to be at a stop sign turning left or right onto a road, and just floor it and crank the wheel, the turning and extra load put on by wanting to accel very fast will bring any clicking if the joint is starting to go.

 

I would suggest doing this a couple times, and remember to turn both ways, left and right.

[Guest subyroo]

Just go to a large carpark or clear area, when it is empty and quiet, put the car into a full R/H lock and drive slooooowly around in circles with your head out the window - listening for the click - click - click. Then do it in the opposite direction, this worked on my wifes Subaru Sherpa (bloody little beast) and my daughters Ford Laser.

 

You will do better with one buddy in the passengers seat also listening, and another (if you have that many ) standing in the centre of the circle listening too.

[Guest Legacy777]

pagan if the joint is marginal, you won't really hear anything unless it's under load, which is why I suggested to turn corner and floor it.

[Guest PaganQWA]

I dont know that I would floor it... that could snap a worn CV and youll be sitting there swearing up a storm I'd go with subyroo's diagnosis. They will click even if you drive slowly as longa s you have the wheel locked all the way in one direction. If they ONLY click under extreem load around corners or taking off they are not worn enough to even worry about. My CV's have been clicking for years, and ONLY when the wheel is cranked all the way. I'm not even worried about them. I just dont lock the steering wheel for any turns. If I need to make a sharp turn I'll jsut do a 3 point and save the CV's, my money, and time

[Guest Legacy777]

Well mine only did it when it was under load.

 

Let me rephrase how I would go about diagnosing.

 

Do subyroo's way, slowly in a circle wheel cranked all the way. If you hear the click then yah they are needing attention...ie replacement.

 

If you hear nothing when going slowly, try my way, you don't have to floor it, just take off with some umph, and that should be enough to notice it.

 

Mine only did it under load, and I swore I was hearing things, but couldn't reproduce it using the above mentioned slow turning with wheel cranked. I finally figured it only did it when I turned a corner from dead stop while accelerating. Even if they only do it under load, you will need to eventually replace them. As to when is sorta up to you, you could drive them and run 'em dead, they could last for years, or a couple months. It's sorta a crap shoot.

[Guest PaganQWA]

I'm go'n for broke on my battle wagon's CVs!

 

/me throws the dice

[Guest subyroo]

. .

too bad PaganQWA, next player :evil:

 

:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

[Guest EQUALIZERplus]

The CVs are something that I used to have to replace almost every year on my old GL. I couldn't always diagnose it when on the flat/level and pulling into an intersection or sharp turn unless they were reeeal bad. If you live in a state like WV w/plenty of steep hills it is easy to deturmine by the methods already covered by the technical staff above. Sounds like you already figured out the problem, but thought I'd throw this in as a little extra if it ever comes in handy. Times that I could never get the CV to click, I'd stop. Accelerate at a tite angle up a steep grade. Same click-click or clunk-clunk. This put the car under enough load to do the diognostic. Hope it helps.

 

Adios amigos,

 

eq

[colossal_monstrosity]

The variation in replies to this topic is outstanding and odd at the same time. CV's are quite simple to replace, not very expensive, and usually very easy to tell if they need to be done. I'm not sure about the rear CV's in AWD cars, but in any car, if the front ones go, you will damned well feel it in the steering at highway speed. The speed it happens generally seems to indicate how bad they are. The steering wheel will just in general vibrate all over the place and not be very smooth...it will jump, anywhere from 5-6 mm, back and forth, left and right, best way I can put it. As for them going bad, well, the boots generally blow up and fling their grease all over in the engine compartment. A guy at the parts store once told me that if breaking the boot isn't what kills them, if the u-joints in the axles actually go bad, that in itself is suppossed to make the boots crack, so you know they're bad.

 

Let's review:

Your CV's are bad if you can tell there is something wrong while you're driving, and it's not your alignment or your tires.

OR

Your CV's are bad because the boots have cracked/broken/spontanesouly combusted and let the grease fly everywhere

OR

they fall out

 

So, if they look ok, and you can't tell from your driving, most likely they're fine. With how much I'm sure you paid the dealer for the tranny, and it sounds like you're installing it yourself, why not just spend another $150 for new CV's? Isn't your objective in all this to make the car work better? If you wanted to save money, you shouldn't maintain your car. Hell, you shouldn't drive.