Fellow Member (>400)
Join Date: Jan 2004
Location: Washington, D.C.
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Front Ball Joint Removal Tip
Don't know if this will help anybody, but I recently replaced all the suspension links and shocks/struts in my wife's 530i. Granted, not an M5, but still an E39 and with the exception of the tie rod placement, pretty much the same process. I generally followed the biesan systems DIY, along with the Bentley manual. One thing many members have had issues with is popping off the ball joints on the wheel carrier side for the control and thrust arms in the front. I bought the $19.99 harbor freight tool, which works just as well as the BMW tool. Unfortunately, what I found out the hard way is that 1. at 97k miles, the torque required to pop them loose was unreal and 2. you can in fact break the tool (see picture below). You think the "bang" when the ball joint lets loose is loud - try having the tool crack. My neighbor came running over to make sure I hadn't killed myself.
In any event, I had to buy a second tool and struggled with getting the thrust arm ball joint loose and then decided that since I was replacing everything I would pull the wheel carrier off with the arms still attached. I then laid the rotor face down on a pad, which gives you full access to the joints AND plenty of room to apply a breaker bar and make full turns to torque the tool. When you feel like it can't crank anymore, take a dead blow hammer and hit the tool on the pressing side (nut side) and "bang", off it goes. What took 45 min on one side took 5 on the other. Live and learn.
Removing the wheel carrier (assuming you're replacing the thrust and control arms), only requires removal of the two bolts at the subframe side and the ABS sensor at the hub (place a padded floor jack under the rotor to avoid damage). See pics below (and yes, I know the thrust arm is upside down, was just placing it in there for illustration).
One other thing - the biesan systems shows using bar type clamps to compress the springs to remove/replace the shocks. I found that works just fine on the rears, but the front springs require a ton of compression and the clamps tend to hit the upper spring mount and/or slip. I spent nearly 1 hour getting one spring apart. Then called my local merchants tire and asked if I could use their wall mounted strut compressor. Took all of 15 min to compress, strip and insert the new strut and bolt it all together. Best $20 I spent on the project and a lot safer.
Majority of the suspension links at the subframe side (both front & rear) looked ok - no visible tears, etc. That said, the wheel carrier sides showed lots of wear - torn boots, leaking & lots of play at 97k miles. Depending on your mileage, you may be better off replacing the entire arm as just doing the thrust arm bushing might overlook the balljoint side that seems to take the brunt of abuse.
Oh, and the car feels fantastic again.