Hyundai Elantra, 2009.
Clicking when going left. RF CV axle suspect. LF new.
Read/viewed videos. Looks do-able.
Is this a great excuse to get an electric impact driver/wrench?
Castle nut on knuckle, axle nut - re-use?
Banging on exposed CV axle - does this push the axle further into the transmission? is there a better way to do this besides making the axle nut flush with the axle end?
Is this a great excuse to get an electric impact driver/wrench?
WHY DO YOU NEED AN EXCUSE TO GET TOOLS!? 
Castle nut on knuckle, axle nut - re-use?
No. Not a good idea. BTW, when you go to remove the castle axle nut, be sure and get a center punch and knock out the dimple that was put in the nut to keep it from turning when it was installed. This makes the removal job about 500% easier. 
Don’t forget to punch a dimple in the new nut once it’s torqued down so it won’t back out on you at the wrong moment.
Banging on exposed CV axle - does this push the axle further into the transmission?
Well, try not to bang on it unless there are no other options. But there is play on the transmission side that will allow the axle to slip out of the wheel side without damaging anything just by going into the transmission side deeper. Be sure not to let the axle hang from the transmission, though, because that can damage the oil seals.
The castle/axle nuts you refer to are retained by cotter pins. So the castle/axle nuts can be reused. Just install new cotter pins.
You can use a heavy rubber mallet to knock the half shaft out of the hub.
Tester
@Tester Not on all cars. I’ve had a number of Hondas on which the axle nut was held in place by a dimple that you make with a center punch. But you did point out an error where I said “castle” when I meant “axle” up there. I’ll fix that now.
This vehicle doesn’t use a dimpled axle nut. The axle nut is retained with a cotter pin.
And with the dimpled axle nut on Honda’s? They can be reused.
You just re-dimple them again with a punch to retain them once the axle nut is torqued.
Tester
It always made me nervous to re-use them, and since they were, what, under 5 bucks, I just put a new one on. I didn’t like the idea that twice-bent metal was standing between a safe drive and a potential wreck, even though I realize that you probably won’t be dimpling the exact same spot twice.
Of course part of that is that those old Hondas I was working on were used cars from the rust belt and so I almost compulsively replaced nearly everything I took off.
I live in Minnesota, and I’ve never replaced a staked Honda axle nut.
Tester
Thanks very much - interesting
…
Say, would anyone be able to cite the dimensions of the cotter pins and save me some trouble? I suppose the lock washer and maybe castle nut I’ll have to drive around town looking for… or wait for it to ship…
Will the tranny fluid need to be changed, as it will leak out?
The proper size cotter pins will be in this inexpensive kit you can get at almost any auto parts store.
Tester
Are you going to just replace the outer CV joint, or the entire half shaft? On some vehicles it is very difficult to replace the CV joint, so if that is your plan, make sure you have the complete factory service manual procedure at your disposal. You should have that for reference even if you are replacing the entire half shaft.
I can’t speak to problems you might encounter w/ your Hyundai, but I’ve diy’er fixed/maintained CV joints on my Corolla and a prior VW Rabbit. Both front wheel drive and used non-staked castle axle nuts with a cotter pin, which I just cleaned & re-used. It’s a bit of a challenge to remove the axle nut b/c it is on there so tight. I wouldn’t use an impact hammer for that job myself. Some finesse is needed for that job. I found the best method is to use a 1/2 inch drive breaker bar and appropriate sized socket, and stand on the bar to get the initial budge. Likewise , I used a similar method to tighten it, estimating the torque by my weight and the distance I stood away from the center of the axle. No jumping.
There’s some challenges with disconnecting ball joints as I recall as part of this job. You need a special tool for that. I used a tool that looks sort of like huge fork. I think the pros here might discourage that method. There’s a better tool available for that job I think. But for me the giant fork worked ok. That infamous diy’er book “How to keep your VW alive for the compleat idiot” – something I can relate too … lol – it said you could do it by whacking the ball joint with two ball peen hammers simultaneously , but I never tried that method.
When you remove that ball joint, assumingb that is required for your car, be careful as the two sides can be under a lot of spring-like force, and can jump as soon as they are freed. So tie them together with some strong rope to minimize the damage they can do when they become free and jump.
Sometimes the shaft will just slip out of the hub w/no problem, and sometimes I’ve had to bang on it a little. I never bang on it w/a steel hammer. I’ll first try what Tester above suggests, a rubber hammer. Next I’ll use a steel hammer but with a sizeable block of wood as a buffer. Still a no go? Then I’ll use a brass drift tool as the buffer. One of those three has always worked for me. Sometimes it helps to turn the wheel a little this way and that way. Best of luck.
@GeorgeSanJose
you asked for it 
A pickle fork will very possibly/probably bust the ball joint boot
At which point, you should replace the ball joint
My point is this . . . if you use a pickle fork, you should have a new ball joint, tie rod end, etc. on hand, as it may very well be damaged
I’ve used the 2 hammer method . . . it works. To be clear, you do NOT hit one hammer with the other. One hammer is the back up hammer, behind the knuckle, tie rod, etc, while the other hammer strikes the tie rod, knuckle, etc. The back up hammer absorbs some of the hit, and you “break the taper”
There are plenty of “front end” kits out there that include ball joint poppers, tie rod poppers, pitman arm pullers, etc., all for a decent price. OTC has such a kit . . . 5 piece, in a box, for roughly $100
Oh that - glad I asked. Found this, has a video, but maybe it’s an earlier model:
… I have a feeling this job won’t be finished anytime soon…
uh-oh - I put on new brake rotors/pads/hardware - rotors looked really bad, pads maybe ok - greased the sliding surfaces … and got a hands-on look at the axle boots - no breaks on the boot - and I can’t detect any click sounds anymore… I think I mis-diagnosed this.
I’ll hang on to the reman cv axle and other stuff I’m collecting though, pick this back up sometime later…
…just starting to read about balancers - there’s an impressive looking boot in the middle of the installed original axle, but the reman just has some grooves - no boots. the shop I bought it from says it should be all fine, they are different ways to balance the axle…
… and carriage returns work on the desktop site…
you got a cheapo axle, and they tried to rationalize the missing dynamic damper
when they remanufacture/overhaul an axleshaft, they’re supposed to transfer that damper
The grooves are the proof that the axleshaft SHOULD have the damper. But they’ll never fess up to their laziness
I bought a pickle fork about 40+ years ago, and used it for 2-3 years till I learned about the “2 hammer” method.
FYI - the Harbor Fright ball joint tool looks like it will work. Stay tuned …
Are balancers expected to be on each axle?
If you buy a high quality axleshaft, yes it should have the damper, same as the original
But if the original didn’t have a damper, then the aftermarket also won’t