Rear CV axle question

[SmashedGlass]

I talked to an older friend of mine yesterday, who purports to have experience with old Subaru's, and explained the noise I'm getting from the back end (posted awhile back on here). He says it's definitely the rear CV joints; his reasoning is that when they dry out or the grease gets old, the cage and bearings in the CV wear and start to make a ticking sound. Does this sound plausible? I have no tears in the boots, no notable play in the shafts, the diff has been drained/filled and no chunks came out, and the drums and shoes have been replaced and work fine. Putting it in 4wd makes no difference to the noise either; it's just a steady tick-tick-tick that I hear at low speeds whether the brakes are applied or not, fwd or 4wd.

 

His advice was to take the CV's apart and "reverse" the cages...which is more work than it's worth as opposed to just being safe and buying new ones, if they actually are the problem.

[nipper]

Er ... no. If that was the truth we would all be having issues. CV grease is different from axle grease (generic term) and doesnt really dry out. Cage reversing is so much work IF it was a cv joint would be easier just to get a rebuilt axle.

 

Rear cvs do such little work compared to the front, that both cages see the same wear and tear. It is not like the front (for arguments sake only as I would never ever recomend this) where the outers see more stress then the inners.

 

Can you post the thread here to refresh our memories?

[SmashedGlass]

Can't post the OT (I'm on my phone atm) but basically:

over the last two months I've been experiencing an ever increasing ticking sound from the rear of the wagon. I can only hear it at low speeds (i.e. Reversing or cominng to a stop) and it is there at the same level whether I apply brake or coast. Inspected everything with the drums, drained refilled diff (no chunks/excessively bad oil), and shake tested the axles. Can't figure it out. It sounds like when you have something stuck in your bicycle rim. Odd things is I can't replicate the sound with rear jacked up and spinning the tires by hand. Baffled and concerned.

[desertsubaru]

Did you check the Universal joints?

[nipper]

Did you check the Universal joints?

 

 

I agree, sounds typical.

[idosubaru]

My money is on the wheel bearings.

 

Driveshafts can tick though too.

 

Mechanics stethoscope on the strut springs can sometimes verify the ticking while turning the wheel by hand.

 

Infrared temp gun after a nice stint on the highway can also verify a bad bearing. Compare 5-20 different spots on the drivers and passengers side and one side may start to show 10 - 50 degrees hotter than the other.

 

Driveshafts - Yank it by hand and look for play. Visually inspect each joint - sometimes you can see wear/fresh metal from play. Ocassionally some are simply seized and have no articulation - so they feel fine on the car and don't reveal their failure until you actually drop the shaft and notice the seized joint.

 

you can unbolt the 4 12mm bolts at the front of the diff and drop the rear half down rather easily and inspect those two ujoints.

[SmashedGlass]

Wheel hubs in the back don't get warm at all (to the touch); check that regularly, after what I went through immediately after purchasing the Roo with the front bearings. And it's not a growl or a rasping sound, just a straight rhythmic tick. So I don't really suspect them. I will get back under her today or tomorrow and dig deeper, maybe drop the drive shaft and inspect those U-joints, that sounds like a plausible cause too.

 

Like I said though it's perplexing that I cannot get the sound to repeat once I have it up in the air and spin things by hand

[987687]

I had a driveshaft go bad. It was kind of a clunk clunk clunk sound. And went with speed. If I put it in 4wd cruising down the road the noise would go away for a few seconds till the driveline started to bind. Then it would make the noise but louder.

[nipper]

Up in the air it may not make noise. There is not enough drag on the driveline (driveshaft) to cause the noise.

[AKghandi]

Sounds like somthing rubbing on the tire to me. But without actually looking at it this is just a guess..

 

ive found wheel bearings are more of a howling than a ticking untill they go really bad but you would know if that was the case

But a striped hub may make that noise

 

 

It doesnt sound like a major issue its just tracking down the noise and figuring it out

 

Good luck.

 

And a to cheer you up.

[nipper]

Once you rule out the driveshaft (may have to take it down to triple check) sometimes you just have to let a noise get a little louder to find it.

[SmashedGlass]

Sounds like somthing rubbing on the tire to me. But without actually looking at it this is just a guess..

 

ive found wheel bearings are more of a howling than a ticking untill they go really bad but you would know if that was the case

But a striped hub may make that noise

 

 

It doesnt sound like a major issue its just tracking down the noise and figuring it out

 

Good luck.

 

And a to cheer you up.

 

Yeah, you should've heard the front of mine when I bought it; sounded like someone trying to cheese grate a block of aluminum :-p

As for the noise, I'm pretty sure it isn't harming anything, it's just really annoying.

Did get under her again yesterday (bless this unseasonably warm spring in Colorado!) and the u-joints on the driveshaft are indeed toast, the rear one the most. May be the problem, we'll see after I replace all three bearings and the carrier just for assurance. By the time I get done with this wagon I'll be able to sell it as NEW lol.