CV Boot DIY procedure questions

[Dupersenior]

I'm getting ready to do replace the front outer CV boots (both sides) next weekend, and I have a couple of questions about the process for those who have some experience with it. I've read a ton of different DIYs on xoutpost and other places, and it seems like there are a lot of options on how to do it.

I've seen the DIY that removes the driveshaft from the differential, and then pulls out the whole axle with the steering knuckle still attached. I'd rather not do that though, because my inner boots look fine and I'd rather not mess with them. So I'll be going the regular way of driving the CV joint stub out from the steering knuckle, and then repairing the joint from there.

My first question is, how much of the suspension do I need to remove before I can drive the axle out of the steering knuckle? Xoutpost's "official" DIY (here) calls for removing the brake caliper and rotor, and all suspension and steering components attached to the steering knuckle, so that when you drive out the CV joint stub, the knuckle is completely off the car. At the other extreme, it's been mentioned in other threads that you can simply remove the lower control arm from the subframe, and that will allow enough movement to drive out the CV joint stub. What are the disadvantages to just unbolting the lower control arm, and leaving everything else intact? Is it just to get more room to work with, or is it easier to drive out the axle if everything else is removed? I'll have the car up on a lift, so if it's just a question of getting more space, I can probably get away with leaving most of the suspension intact.

Second question:
I've seen some people mention to punching the CV joint stub out from the steering knuckle with an air hammer, or even a sledgehammer and drift. Is there any risk to doing it this way? The Bentley Service Manual specifically says not to pound on it, but it seems to work for some people. Ideally, I'll rent the hub puller that bolts into the lug nut holes in the wheel hub, but if I can't find it, I'd rather not use an arm-style puller and risk screwing up the dust shield.

Third question: any tips on driving the cv joint stub back into the steering knuckle?

Whew, that was a long post. If you don't feel like responding to all 3 questions, the first one (about how much I need to disassemble) is the most important.

Thanks!

[Ricky Bobby]

look up the thread "CV boot changed in 30 minutes" or something like that, thread, much easier than the official DIY on the forum.

Basically take off the axle nut, unbolt caliper and rotor and ABS sensor, and 2 nuts/bolts from the strut to give it enough room to swivel.

Take a hub flange tool or axle puller tool that bolts to the hub and use the rod that comes with them and is threaded, to "push" the axle inward and out of the hub. When you have the strut disconnected once the axle is pushed inward you will have enough room to get it out there. Then just pop the CV joint off and replace outer boots on both sides.


To get the axle back into the hub, unless you have a special tool which draws the axle in, just take a 2x4 and a big ass deadblow hammer and hammer like THOR THE GOD OF THUNDER until you got enough threads showing to get the axle nut on, and torque to 300 ft lbs.

I wouldn't hammer the axle out of the hub, you can damage it that way. Use either a jaw puller (you can damage the dust shield though this way) or a hub flange tool to push it inwards, then you lessen risk of damaging the axle.

Also, some BMW mechs on the forum say you can just disconnect the wishbone control arm at the frame and you dont have to disconnect the strut, however, that wishbone needs to be torqued on reassembly with the wheels on the ground, so to avoid that, I find it easier in my research to just unbolt the strut, and avoid touching the control arms/ball joints.

Btw, use a new axle nut if you didnt get one in your CV boot kit, they are cheap.




I only know this info from the past 2 months researching the best way to do my wheel bearings, subsequently I will be doing my outer CV boots at the same time since basically the disassembly process is the same (you have to be able to get the axle out to replace wheel bearings)


hope that helps!

[stevekat]

I used a rotary hammer drill in hammer only mode to push the axle out of the hub using a bull point chisel. Worked very well.

When I replaced my axles (rather than the outer boots) just removed the lower control arm from the chassis.

[amacman]

Originally Posted by stevekat

I used a rotary hammer drill in hammer only mode to push the axle out of the hub using a bull point chisel. Worked very well.

When I replaced my axles (rather than the outer boots) just removed the lower control arm from the chassis.

What he said .
The axle will release eventually with some WD40 and gentle persuasion .
Best to read the diy write up for more info .

http://www.xoutpost.com/bmw-sav-foru...0-minutes.html

[hoaesq]

One thing to consider is - if the boots are torn, then you're more likely to have grit and all sorts of junk kicked up from the road in them. You should rebuild or at least clean out the joints and regrease them. I contemplated with replacing just the boots but it just made more sense to change the shafts since I was already half way there in terms of work.

Just my 2 cents.

[pezho405]

I wouldnt remove the axle from the diff part. what i did was hold the Alex with a big Gozovii kluch (idk in english) so it doesnt pop out and hit it with a hammer on the stip like you said also use a pry bar to ..sorry im no use..


But a usefull part is when putting the hub back on the shaft, use a ziptie over the little ring pin in the end of the shaft for easier getting it on, but just remember to cut it off before sealing up the rubber!

[upallnight]

If you're going to rebuild the CV joint, here's a video on how to do it right, especially getting the axle and circlip back on the joint.

Rzeppa CV Joint Dismantle, Clean & Grease How to DIY: BMTroubleU - YouTube