[left123]

If you need to replace your Lower Control Arms (aka, tension struts per BMW) or your front Lower Control Arm Bushings (aka, thrust rod bushings per BMW) are worn, hopefully this DIY will help you change them yourself. My car is a e90 06 330i but this procedure should work for other e9x cars.

Standard warning: You are jacking up your car and this is inherently dangerous. I am not responsible for anything that happens to you, your car, your buddy or your house. Take care of yourself and be very careful as you complete this.

This process is not difficult if you are patient and confident using handtools.

REASON I REPLACED MINE: My left bushing was leaking (BMW factory bushings are hydraulic fluid filled) which caused me to fail VA safety inspection.

WHY REPLACE THE WHOLE ARM INSTEAD OF JUST BUSHING?: Labor. Yes, the bushings themselves are cheaper than the arm but I do not have a press that removes/installs bushings. The arms with bushings installed are more expensive (marginally) but much easier to replace. A local dealer quoted me $650 to replace just the bushings. I replaced both arms w/bushings pre-installed for ~$180.

PART I USED TO REPLACE:
Meyle HD Lower control arm (pm me for site. Not sure if mod's will allow me to put the website)

3160350005/HD (left) &
3160350006/HD (right)

I bought the HD versions as it seemed a logical upgrade from the standard stiffness. Doing it again I would have replaced the upper control arms (I believe these are called "wishbones" as well) with these and I would have used the M3 versions. I have no reason for this change other than I like the idea of the M3 suspension components. Mine rides just fine and was cheaper than the M3 parts. If you are planning on upgrading other parts of your suspension or just have the $$$, go for the M3 parts.

TOOLS NEEDED:
Floor jack
Jack stands (2)
wooden ramps (nice to have, not needed)
Torque wrench (need ~125 ftlb force)
socket wrench (I used 1/2 in size)
sockets: 17mm, 18mm, 21mm + 8mm (I think its 8mm, for plastic tray screws)
block of wood (I used 2 pieces of plywood screwed together: ~6"x8”x1.5’’)
anti-seize compound (I used Permalite Anti-seize, #81343)
headlight
protective eyewear
pipe extender (for extra torque when removing bolts/nuts)


STEPS:

1. Jack car, put on jackstands (I built wooden ramps to drive on to facilitate this process. I also use a hockey puck between the jack and center jack point for grip and to minimize scratching). See pictures below:





2. Remove wheels (17mm socket). You might need to kick/shake/pull hard to get them to release. Mine did. (brush/clean hub surface and wheel surface to minimize this for future)



3. Remove plastic undertray. I had 17 screws, all 8mm I believe (size could be wrong as I neglected to write that down).







4. Next, from under the car loosen both the bolt through the bushing (18mm) as well as the nut on the opposite end of the lower control arm (21mm, attached to steering knuckle). I first sprayed the 21mm nut/bolt with WD-40 to loosen it/break the grime. I had to use an extender pipe on my 1/2'' socket wrench to be able to loosen the 21mm nut.

Ideally you would use a 21 mm deep socket as the brake shield is in the way but I was able to get a regular socket to fit through some finagling. (I left the bolt through the bushing attached so the arm was up out of the way).





NOTE: The 21mm nut kept spinning and would not come off. After realizing the entire bolt of the control arm was spinning, I had to C clamp the arm above the bolt to the steering knuckle to stop it from spinning. Came right off after that.

EDIT: See post #4 below from Rotorocious about using a torx to keep it from spinning

"Also if you look at the end of the arm on the knuckle side where the stud is, there is a spot to insert a torx socket to keep it from spinning. The T-40 attached to a ratchet, with a 21mm wrench already on the nut, this worked great to hold it still and tighten it up before final torque-ing ."




5. Pull out the old control arm. It just comes right out. (the picture below is a new right and an old left lower control arm)



6. Apply anti-seize compound to both bolts, then fit new arm in place. I then started both bolt/nut, then I loaded the front suspension before I torqued the bolts. To load the suspension, I used a block of wood (2 pieces of plywood screwed together. 2x4 works fine, just didnt have a piece). This part came from CalWaterBoy's write-up here:


6a. To load the suspension to the appropriate level, jack up the hub with your floor jack until the bottom of the hub to the fender measurement is 18.7'' (again, from Calwaterboy).

new arm/bushing in place:


new arm/lower nut in place:


loading the suspension w/wood block:




6b. Torque the bolts/nuts. Below are the torque specs (from Calwaterboy again)

Bolt through bushing: 74 ftlb (100 Nm)
Nut at steering knuckle: 122 ftlb (165 Nm)

NOTE: Be careful when torquing these as the car is up on jack stands + the hub is jacked up with wood. I felt comfortable but you will need a very healthy dose of force to make the torque wrench "click" at 122 ftlb. Go easy first and feel out the force you'll need to make sure your setup is stable.

7. Lower the hub after torquing.

8. Repeat for other side of car.

9. Re-attach the plastic tray and all 17 screws.

10. Reinstall wheels. 88 ftlb of torque for lug nuts.

11. Raise car off of jack stands, then lower onto wooden ramps (or directly to ground).

11. Take on test drive. Go easy first to make sure everything is good to go.

Hopefully this is clear for you to follow. Good luck with the install.

[e90gene]

What did you use between jack stand and plastic jacking point?

[left123]

All I use is a small, cut piece of hardwood that fits up into the plastic cover at the jack points. The jack stands then rest on those not the plastic.

[Rotorocious]

I just did this last night. Thanks for your DIY.

Another way to do it was just remove the inner fender liner instead of the belly pan. Doing it this way I was ably to do one side at a time with just a jack and jack stand. It's probably easier to remove the pan but I hate doing it haha.

Also if you look at the end of the arm on the knuckle side where the stud is, there is a spot to insert a torx socket to keep it from spinning.
The T-40 attached to a ratchet, with a 21mm wrench already on the nut, this worked great to hold it still and tighten it up before final torque-ing .

It's a T-40

And be careful not to install the control arm upside down like I did the first time

[mlifxs]

I had problems using a wood block, as pictured. I used hockey pucks instead, seemed to be more stable. Used hockey pucks between jack stands and jack points as well.

Nice writeup. The Meyle HD tension struts are a great replacement / upgrade.

[left123]

Originally Posted by Rotorocious

I just did this last night. Thanks for your DIY.

Another way to do it was just remove the inner fender liner instead of the belly pan. Doing it this way I was ably to do one side at a time with just a jack and jack stand. It's probably easier to remove the pan but I hate doing it haha.

Also if you look at the end of the arm on the knuckle side where the stud is, there is a spot to insert a torx socket to keep it from spinning.
The T-40 attached to a ratchet, with a 21mm wrench already on the nut, this worked great to hold it still and tighten it up before final torque-ing .

It's a T-40

And be careful not to install the control arm upside down like I did the first time

Very interesting about the torx bit. I wish I knew that as there had to be a design built into it to keep from spinning. Nonetheless, the c clamp worked great.

[left123]

Originally Posted by mlifxs

I had problems using a wood block, as pictured. I used hockey pucks instead, seemed to be more stable. Used hockey pucks between jack stands and jack points as well.

Nice writeup. The Meyle HD tension struts are a great replacement / upgrade.

I agree about the pucks being more stable. I'd like to make a two puck system though with one cut to fit into the plastic hole and glue that to another puck for a wider base.

[DaytonM_330xi]

Great diy, but I have a 06 330xi and suspension is different. I did mine a little bit ago.

[left123]

Originally Posted by DaytonM_330xi

Great diy, but I have a 06 330xi and suspension is different. I did mine a little bit ago.

Interesting. Didnt know it was different for the "x" cars but that makes sense. What is different about it?

[DaytonM_330xi]

It looks a little different like placement of the arms and the ball joints are actually pressed and bolted on the spindle not the arm. Meaning one end of the arm just has the hole to slide onto the ball joint and secured by the nut.

[München]

yes it can be done.





just buy this tool and make sure to preload the suspension when tightening it back to spec with using obviously a torque wrench.

[msp2three35i]

great DYI, thank you.

i have the passenger side done, however i overtorqued the bolt that goes through the bushing on the drivers side. I just got a new torque wrench and i was reading the measurements wrong. now the bolt just spins freely in both directions neither tightening or loosening. not sure what to do, any advice would be appreciated. thanks.

[Multibimmer]

Nice write-up - thanks. Very easy job. The worst of it is getting the wheels back on, thanks the BMW's ridiculous design of using lug bolts instead of studs. Otherwise, zero problems.

[mrgreenwood]

Does the knuckle spins while torquing the nuts

[shadowx360]

Originally Posted by left123

All I use is a small, cut piece of hardwood that fits up into the plastic cover at the jack points. The jack stands then rest on those not the plastic.

Hey, OP, I have a 2006 330i as well, but when I was following the guide, I wasn't able to preload it to spec, my car started to lift off the jacks around 20". Maybe it's because I have the sports package which tightened up the springs. Do you think it makes a difference? My camber seems a little off but it's dark so I can't be sure till I have them check the alignment tomorrow.

[left123]

Originally Posted by shadowx360

Hey, OP, I have a 2006 330i as well, but when I was following the guide, I wasn't able to preload it to spec, my car started to lift off the jacks around 20". Maybe it's because I have the sports package which tightened up the springs. Do you think it makes a difference? My camber seems a little off but it's dark so I can't be sure till I have them check the alignment tomorrow.

No, I do not think that it really matters if you are an inch or two off. All that really matters is that it is preloaded to approximately what it would be when it is on the ground. You are just preventing the bushings from being torqued when you put the car on the ground if you didn't preload it.

I also had the sports package so I do not think that impacts it, but just go with what you are getting.

Good luck.

[Okbye2]

Everything went well as per your explanation. I had a humming noise and improper tire wear because of a worn bushings from the control arm. When i went for an alignment they told me it was the control arm. They wanted to charge me $250 per side. I bought the arms from ebay for $80 for both. Followed these instructions and 2 hours later (taking my time and had some rain) everything went as per these directions. Thank you!

[asiemers]

Originally Posted by msp2three35i

great DYI, thank you.

i have the passenger side done, however i overtorqued the bolt that goes through the bushing on the drivers side. I just got a new torque wrench and i was reading the measurements wrong. now the bolt just spins freely in both directions neither tightening or loosening. not sure what to do, any advice would be appreciated. thanks.

I'm having the same problem. I had no choice but to leave it. There was no play in the bushing end so I just put the wheel back on and went on my way. If the bolt can't be taken out since it just spins in place I can't imagine it coming loose either because I tried everything.

[FrankyGTR]

Same thing happened to me with the bushing bolt on passenger side it just keeps turning.anyone know the fix?

[cranelec]

Assuming you are referring to the ball joint, did you look at the picture with the Torx T-40? If you are referring to the sub-frame bushing, try a 4.5" grinder with a cutoff wheel.

Very bad things happen to BMW drivers with loose suspension bolts.

[J. Dub]

I thought the bolt through the thrust arm bushing is not to be reused. Am I wrong?

[jin]

Originally Posted by asiemers

I'm having the same problem. I had no choice but to leave it. There was no play in the bushing end so I just put the wheel back on and went on my way. If the bolt can't be taken out since it just spins in place I can't imagine it coming loose either because I tried everything.

Exact same thing happened to me. Torque spec was 75 ft/lbs + 90 degrees. The fix is to put another hex nut on it then torque it down.