1
My passenger side front was complete in just over an hour with a couple of us working on it, yet I sheared a vital bolt on the driver’s side. The car was going nowhere for a week, whilst I removed the hub and tried various techniques to remove the offending bolt. Luckily, I have access to an engineering workshop and the correct metric fine taps and other tools to remove and rethread the hub; without it could have been a lot worse... So please be warned.
It was my impatience to get the job done, that meant I took short cuts and ended up with a sheared bolt... So I’ll describe the ideal way to tackle the job. As long as you follow the procedure as described, you should be ok. Obviously I assume you have a fairly decent level of common sense and mechanical understanding to try doing this yourself, however I take no responsibility for any mistake/injury/damage to your car that you may make following my guide – it is an account of how I tackled it, and you are welcome to try, using my account as a reference.
I suggest having someone on hand to help; there are a few bits were another set of hands makes things easier. And ensure you use the right tools – without it’s just not viable to do it yourself. Buying some of the tools if you do not have them may end up costing the same (if not more) as getting someone to fit them for you – but at least you will always have the tools for future, use and more intimate knowledge of you own car. Not to mention the immense satisfaction of doing it yourself.
One other thing; please excuse the fact there are only a few pics... I got so carried away I failed to take as many as I planned. However, I think I have described myself fairly well, so once you get stuck in all should be clear.
In preparation, a couple days before, call BMW and order 2x new collar bolts (part no. Part no. 31306779487)
Tools Required;
Trolley Jack
Jack Stands
Socket Set (up to 21mm with extensions)
Allen Keys / Hex Key Ratchet Set
Torque Wrench
Spring Compressors
Penetrating spray (WD40)
Wire Brush
Flathead screwdriver and pliers to remove brake calliper clip
To jack the car up at the front, some E46 have a central jacking point; if so use this and get 2 jack stands under the front side jack points. Later cars (2001 on) like mine don’t (to stop amateurs working on the driveway? It wouldn’t surprise me). Because of this, I did one side at a time, using the central wishbone ball joint as my jacking point. This will require you to turn the wheel to full-lock to achieve access for your trolley jack.
1. Crack wheel bolts.
2. Jack up the car from the wishbone ball joint (use a piece of wood inside/on top of your metal jack for better support and pressure distribution).
3. Place jack stand under the front/side jack point.
4. Slowly lower car onto jack stand and remove jack. Now straighten steering wheel for better work access.
3. Remove wheel bolts completely and remove wheel, setting aside.
The shock assembly is ready to be tackled now. It is attached in three places; at the top (three nuts on top of the strut tower, a central connection to the drop link and inside the hub collar at the bottom. There are a few ways to do this, but I find this to be the easiest way.
Note: If you have xenons (I don't), I believe the first thing you should do is disconnect the levelling sensor, as this commonly breaks when performing this job. It can be found behind the shock and drop link end link.
1. Undo the drop link bolt. This requires both a 16mm socket and a 16mm spanner on the back, to stop the ball joint rotating. 16mm is an irregular size and won’t be found in most socket sets. However, if you don’t have a 16mm, use a 5/8 imperial – they are almost identical.
Don't be alarmed by superficial rust - most will wire brush off; it's just on the surface. However, If you find deep bubbling which appears to negate the integrity of a load bearing component, then it would be advisable to change it.
2. I then removed the brake calliper assembly to have more room to move about. This is easily done by just removing the silver clip with a screwdriver and pliers, and by undoing two 7mm hex cap bolts inside the short rubber tubes. Remove the plastic caps and get your ratchet/allen key in there. Once removed, really pull the calliper toward you – this will slowly compress the piston inside enough for it to be pulled off, even over disks with a fair lip on them. Hang the calliper from the spring using a bent coat hanger to avoid placing stress on the brake line. During the entire process be careful not to snag or stress the brake line as this could lead to failure.
Removing the brake calliper piston:
3. Now remove the 18mm hub collar bolt (this also releases the bracket that holds the brake line, ABS and pad sensor wires). Now this is the bolt I sheared on one side – so this requires a degree of care and attention to do correctly. As my car is now 6yrs old, there was some superficial surface corrosion and an amount of seize on some of these high-tension bolts (newer cars may be easier).
Now to ensure I didn’t make the same mistake twice, I wire brushed the end of the bolt that protrudes out of the end of the collar. This will remove some of the surface corrosion from the thread – you don’t want to try pulling all that crap through as you undo. Douse in penetrating fluid and spray more in the gap of the collar. Leave to soak half hour. Spray on more and then using a spanner (NOT ratchet – a spanner allows you to work it backward and forward to release the threads), try to release the bolt. This will be hard and require some force – the bolt has threadlock on and is done up to 60ft/lb of torque. You may have luck, you may not. Watch the end of the bolt to see if as you get movement proportional to that on the head. If it’s not moving, but the head is, you may be well on your way to shearing it.
Mine didn’t feel good again; so at this point I dug out my gas torch and heated the fcuk3r up (ensuring all wires/brakes lines were out of the way) to get a little expansion. Try not to get the flame on the bolt itself, but all around the bracket around the bolt, trying not to cook your shock. Once really hot, spray a bit more WD40 on and try to ease the spanner back and forth. If this is fruit less, get a hammer and start hitting the end of the bolt to further try and internally shock the threads (a tip given to me by my local mechanic). Get the heat back on it, a bit of WD and keep trying to move the spanner back and forward. It may seem fruitless, but keep repeating this and you will get some joy. I was already resigning myself to fact that this other one may shear, and then the back and forth movement became easier. At this point I would spray on more WD, wind it out until it became hard to move again, and then rock back and forth once more. Repeating this continues to release the threads; eventually the bolt will be far enough through to get the ratchet on it and release totally. Phew. By this point you have stressed the bolt so much that it will be useless to use again – I ordered new ones from BMW. Part no. 31306779487 – about £1.40 each. I had a beer at this point I was so happy. You may wish to also.
The motherlover out, and the collar pushed off from the bottom of the strut
4. Ok – hardest part out of the way. Now the collar is undone, the hub will slip to the bottom of the shock. Just ease it down and forward a little until its fully off the shock. You might want to support the wishbone with an axle stand to relieve the stress on the ball joint (you can see it in the above photo).
5. Undo the three 13mm nuts on top of the strut tower (under the bonnet) and remove the complete strut/spring assembly. Someone should hold and press the shock up into the strut tower untill all the bolts are removed and then carefully lower it out.
6. Now get you spring compressors on either side of the spring – try to get as close to 180° deg apart, although this isn’t really possible due to space restrictions. You need to get them on with at least one dormant coil between them each side, and tighten as far as they go. Do one at a time in equal increments. Obviously a coiled spring can be dangerous, so have somebody to help you and be careful. I accept no responsibility for you trying to do this yourself and it going wrong.
Compressors on old spring
7. Pop the black plastic cap of the top of the spring to expose a 21mm nut that holds the cap to the shock. Once the spring is as fully compressed as it will go, then undo this with a ratchet spanner and extension. There may still be some pressure from the spring, and on the final turn the nut and cap will pop off. Carefully remove the spring and wind back the compressors equally until you can safely remove them.
8. Put the new spring in place with the cap on it – this will give you an indication of the best place to position the jaws of the compressors on the new springs, without them fouling the hat or seating. If they do, you may need to start again. Remove the spring and lay it down (not on strut). As before, tighten each side little by little equally until the new spring is compressed. Position the now compressed spring on the strut, and reassemble the washer/hat assembly ensuring the spring is positioned correctly with the notch in the hat – having the spring seated correctly is vital. You may need to compress the hat on the spring whilst somebody else gets the nut on. Once on, tighten the nut as far as it will go. If the shock piston starts rotating as you tighten (i.e. the nut goes nowhere), you can use some mole grips on the very top of the piston (under the hat). Do not hold the bottom – this is obviously the part that moves inside the shock, and damage to this is unacceptable.
9. New shock assembly is complete now, and ready to go back on. Reassembly is the same as disassembly, except you will need to use your jack to get certain bits to fit...
Insert the shock up inside the arch and screw the bolts on strut tower – there is only one way for this to fit due to a location pin. Tighten all three nuts up fairly tight, but not too tight yet.
10. With the strut hanging from the tower, slip the bottom end through the collar and pull the hub up onto the shock. There are two metal location pins protruding out of the bottom of the shock – these indicate the position and should go in-between the collar gap (where the bolt goes through). Use the jack on the bottom of the wishbone to raise the entire hub/collar up until it can go no further (you will see the spring start to compress when that is reached). This is now in place and ready to have the brand new collar bolt tightened. Place the brake line bracket on the bolt, apply threadlock to the threads that will be inside the collar and tighten up. You will need a torque wrench set to 60ft/lbs, and tighten until that is reached.
Using the jack to press the collar up as far as possible onto the strut:
11. You may need to jack the wishbone up a little more until you can get the drop link through its bracket. Tighten up in the same manner as you removed it (spanner on back, ratchet on bolt). At this point go back under the bonnet and tighten the 3 bolts on the strut tower up fully.
12. Ensure both the ABS and pad wear sensor wires, are clipped back into place. Reattach the outer part of the calliper and clip in the brake line. Do up the hex bolts that secure the brake piston and replace the caps.
13. Check everything is secure and in place. Assuming it is, replace the wheel and tighten the bolts (may be easier if somebody presses the brakes whilst you do this).
Everything back in the correct bracket and the shiny new collar bolt showing:
Reinstalled Eibach goodness
14. Turn the steering wheel to full lock so that the front of the wheel is buried inside the arch. This will give you enough room to position your jack back inside and raise the car up off the jack-stand from the main wishbone ball-joint (safe jacking point). Once up, remove jack stand and SLOWLY lower the car. Remove jack. Tighten wheel bolts up fully. Repeat entire process on the other side...
15. Before you go anywhere, pump the brakes - they will need this after you pressed in the piston to remove the brakes.
I’ll add to this a procedure for the rear springs in a day or two.
I hope you find this helpful. If you need anything or any help, just PM me: I'll be happy to help you or talk you through.
Thanks for reading.
Keith
Taken later after install, looking lower and filling the arches out nicely. Excuse the wet, filthy car and wheel...
