As reported a few months back, I discovered that my front wheel bearings were grumbling. When I was in replacing the corroded brake splasher shields, I had the brakes stripped off and this gave me the opportunity to spin up each hub in turn free of any hinderance from the brakes and sure as night follows day, both were slightly noisy and felt just a bit notchy. I hadn’t really noticed any noise in the cabin until a few more hundred miles later and the faintest of rumblings could be heard with the window down and the noise increased on right hand bends as the left hand (nearside) bearing loaded up more indicating that it was on its way out.
The OEM bearings are FAG, just like they were on the E60 when I replaced them.
A pair of FAG bearings was sourced and I set about replacing them. Given that the front lower arm (the tension arm) needs to be removed from the swivel bearing (hub carrier) and I had noticed a crack in the offside tension arm bush and it had just a bit more movement at the same bush on the nearside, I opted to replace the pair of tension arms at the same time.
The Lemforder arms were quite reasonably priced at £58 each. I also ordered a set of fitting nuts and bolts as these are locking nuts and stretch bolts so are strictly single use only at £15 each.
This is how I replaced both the wheel bearing and tension arm on my 2013 535i.
Trolley jack and axle stands
17mm socket for wheel bolts
18mm and E16 socket for caliper bolts
E20 socket for subframe bolt
M12 spline bit
Torx Plus TP60 bit for new wheel bearing bolts
6mm Allen key
24mm ratcheting spanner
Torx T50 bit Preferably impact grade!
Ratchet for sockets
Breaker bar, I used a ¾” drive x 1000mm long and a ½” drive 750mm long one
Hammer (non marking)
New like for like FAG bearings who supplied the original bearings to BMW that were fitted to my car on the production line.
Get the car up in the air on ramps this is partly so I can get my trolley jack under the central front subframe jacking point.
While its safely up on the air, I removed the front underbelly section which is held on with lots of 8mm hex bolts.
Carefully set aside the underbelly and I kept the bolts safe in my magnetic tray. This pile is going to get much bigger!
This now mostly exposes the tension arm to subframe bolt.
Once you’ve got the car’s front axle safely supported see this thread
Remove the front wheel, I use wheel alignment pins to stop the insides of the alloys bashing off the brake splash shield, which hasn’t long been replaced.
Prevent the disc from rotating while you undo the 6mm Allen key bolt that holds the disc to the hub. Depending on how long your discs has been on the car, you may need to persuade it to leave the hub with a soft faced hammer.
Before I removed the disc I carefully removed the brake flexi hose from its supporting brackets as I’m going to stow the caliper above the upper wishbone so its right out the way, its hose is above the tension arm.
The four bearing retaining bolts are visible on the back of the hub carrier (left of centre in picture above) and you will note that the bottom left one is partially obscured by the tension arm balljoint. This is why the tension arm needs to come out to access this one bearing retaining bolt. The 18mm hex original caliper bolts will be replaced with the newer E torx bolts. I also replaced the ABS sensor bolt which is located between the two uppermost bearing retaining bolts. The two black circles are the plastic caps over the caliper sliding Allen key bolts. 9mm in my case, 7mm for the smaller brakes.
Couple of squeezes on the trigger of my impact wrench and the caliper bolts were whizzed out.
Which allowed me to secure the caliper to the upper wishbone with cable ties which keeps the hydraulic line out the way of the tension arm.
To access to the tension arm balljoint nut, I removed the brake splash shield, partly as its new and I didn’t want to damage it.
I loosely refitted the top two brake splash shields bolts as they also secure the bracket that holds the hydraulic brake line and the ABS sensor wire. I had replaced this bracket at the same time as the brake splash shield previously. That's the top two of four bearing retaining bolts just visible above the hub flange. They are exposed by 10-15mm or so and their ends look really crusty. Make sure these have good soaking in penetrating oil.
To get a bit more access to the tension arms subframe bolt, you need to remove the front section of the wheel arch liner which is held in place with lots of 8mm hex bolts.
Which spin out easily, repetitive fixings like this warrant a power tool for quickness and reducing fatigue, AKA, I'm getting old.
But do this first before storing the caliper as I made access awkward for myself getting the top bolts out from the wheel arch liner!
Once the wheel arch liner is out, you can now get access to the tension arm subframe bolt. Access is a bit limited (for using an impact wrench) on mine due to the additional water radiator. I’ll get it with a breaker bar.
The subframe bolt has a nut which is captive on a piece of pressed steel which clips around the subframe and negates the need to hold the nut with a spanner when you undo the bolts. Note the cracking in the bush, another reason to replace them.
Another view from the wheelarch side showing the position of the captive nut and ETorx bolt head on the subframe. I soaked all the nuts and bolts with Plusgas before attempting to loosen anything.
1000mm long ¾” drive breaker bar with a good quality 6 point 24mm socket made short work of loosening the tension arm balljoint and sure enough the balljoint started spinning in the taper. No need to worry about trying to split the taper or get it out the hub carrier as its loose.
Once the taper and balljoint are loose, you need to counterhold the balljoint shank with a Torx T50 bit. I’ve got form for breaking Torx bits on this car so I used my impact grade Torx bit while using a 24mm ratchet spanner to spin the nut off as far as I could until…
…the inevitable happened and instead of the Torx bit yielding it was the actual steel of the balljoint shank started to twist. The nut is a nyloc and gets a fearsome grip on the slightly corroded exposed threads of the balljoint shank.
As the arm is going for scrap I can afford to not be fussy and get a firm grip of the balljoint shank above the hub with a pair of self locking pliers. If you look really closely you can see a bit of deterioration of the bush on the main wishbone where the forked end of the strut bolts to it. I’ve got a pair of wishbones to be fitted next.
Use brute strength to unwind the nut over the corroded threads. I had wire brushed them as best I could and were liberally coated in Plusgas. Heat might be a better option to soften the nyloc.
Tension arm is out of the hub carrier, you san see the slight damage I’ve inflicted on the mushroom head of the balljoint and I’ve dislodged the gaiter from using self locking pliers. This is why I strongly recommend replacing the tension arm when you do the bearings as if the arm hasn’t been recently replaced, you run the risk of damaging it getting it out.
Do not use impact tools to undo these balljoints as the mushroom head of the balljoint has slight spikes on it which bite into the hub carrier. If these spin up with an impact tool you will badly score the inside of the mushroom head face on the hub carrier. Persevere with touchy feely hand tools.
750mm ½” drive breaker bar and an E20 socket was needed to crack loose the subframe bolt.
Swap over to a smaller ratchet to work the bolt out, the coolant hoses are hindering me a bit here. I don't want to rupture them as they disappear into the engine bay with one connecting to the nearside of the radiator.
Saving my elbows as I suffer from tennis elbow, not that I play tennis of course….
Move the coolant hoses to allow the bolt to be removed. It gets fitted from the front to the rear. Using a soft faced hammer, persuade the arm to leave the subframe and lift it out from under the wheel arch.
Remove the captive nut from the subframe. These are handed for each side of the car so make sure you have the correct replacement.
This is why you need to remove the tension arm to access the wheel bearing bolts to give you access for an M12 spline bit to remove the original bearing bolts. Not taking any chances, using impact grade bits again.
Which came loose surprisingly easily given how rotten looking the exposed threads were.
You don’t need to remove the ABS sensor to access the bolts, just be wary of the wire and they will come out o.k. Look how shiny the hub carrier is where its protected from the muck by the bolts!
When a pry bar failed to shift the bearing…
…a few well placed hammer blows on the old flange soon got it away from the hub carrier and I could pull it off the hub carrier
But it left behind the rear cover of the bearing, which required a bit more prising to get it out, being mindful of the ABS sensor.
Some crusty bits were observed, that’s the business end of the ABS sensor at the 12 o’clock position. It reads a disc on the rear of the bearing.
All cleaned up with a wire brush wheel on a power drill and ready for re-assembly
I told you the pile of bits would get bigger…..
Nice new shiny bits ready to go on. Here we have a pair of tension arms with their nuts and bolts at the subframe end, balljoint lock nuts, caliper cradle retaining bolts, brake disc retaining screw, ABS sensor bolt, bearings and their retaining bolts and caliper spring clips. Ignore the drop links, I didn’t fit them at this stage. I want to revitalise the roll bar too so will tackle it all at the same time.
Boring but important teccy bit now.
BMW changed the design of the wheel bearing, all they did was alter the thread pitch and drive of the mounting bolts. The early F10s like mine had a bearing held on with 4 No. M12 with a thread pitch of 1.5mm. These need an M12 spline (double hex/triple square) bit to remove them. All the replacement bearings and those fitted to newer F10s have M12 bolts but with a finer thread at 1.25mm and need a Torx Plus TP60 bit to tighten them. I had to source a set of Torx Plus bits and as back up, an impact grade TP60 bit.
New bolt on left with 1.25mm thread pitch and old 1.5mm thread pitch bolt on right.
New bolt on left with Torx Plus TP 60 drive and old M12 spline drive bolt on right.
Do not be tempted to try and use a Torx T60 (black, right hand side) bit as it’s not the right fit and there is far too much slop. These new bolts are tightened to quite a high spec so get the right tools Torx TP 60 bit on the left. Which means if you replace your bearing make sure you get the correct pitch of bolts for it. My FAG bearings came with new bolts so no worries there.
Fit the new bearing into the recess in the hub carrier lining up the bolt holes. I couldn’t push it fully home but I knew the bolts would pull it tight. Lovely shiny bits.
Commence re-assembly by torqueing evenly the new bearing retaining bolts to 20Nm.
Then torque them to 120Nm. But we aren’t done yet.
The final tightening sequence is to turn them thru a further 90 degrees. To allow me to do this, I pencilled on four vertical lines on the end of the bolts.
Once these were horizontal, I knew they were tight enough. That wasn’t too bad to do. My 750mm long breaker bar was sufficient without too much difficulty.
Install the new arm in the subframe and feed thru the bolt from the front which helps align the new captive nut but do not tighten the bolt anymore than just finger tight as the arm needs to be at the normal position before tightening the subframe bolt so as not to lock in any stresses into the new bush when the car sits back on its wheels and the suspension returns to its 'normal' position.
To get the arm in a ‘normal’ position and to also allow you access the subframe bolt to tighten it, position the balljoint of the arm so there is 20mm between the top of the cup on the bub carrier and the bottom of the balljoint.
Tighten the new bolt (E20) to 85Nm.
And then make some marks on the bolt head so you know when you have turned it thru another 180 degrees. Again, the 750 mm breaker bar earned its keep and wasn’t too difficult to do.
Drop the balljoint into the hub carrier. If you look very closely you will see two little spikes on the mushroom head that ‘bite’ into the hub carrier, this is why you don’t use impact tools on these joints.
Counter hold the balljoint shank with the T50 bit while you do up new 24mm locknut until the taper and mushroom head bite and torque to 100Nm.
Make some marks on the nut and then tighten a further 90 degrees. Turn the hub carrier to full lock so that when you tighten the nut there is something to react against.
Looking good from the inside.
I used a Torx T30 bit to replace the ABS sensor bolt. Torque new bolt to 8Nm. I struggled to get an E39 ABS bolt out when I needed too, so all I'm doing is future proofing it. Bolt was pennies from Cotswolds so while I'm in there and all that....
Re-fit the brake splash shield, torque bolts to 12Nm.
Re-fit hydraulic brake line.
Re-fit caliper/cradle with new bolts. BMW changed these from 18mm hex to E16 Torx.
Torque caliper cradle bolts to 110Nm.
Make sure the brake disc is fully seated onto the bearing hub spigot, my wheel alignment pins help position the disc correctly. Inserting a couple of wheel bolts will also help position the disc on the hub. The new disc retaining screw is tightened to 16Nm.
I fitted a new brake caliper spring clip, looks so much better. Make sure its fully installed, the centre pin sits in a recess in the caliper cradle and that the clip site vertical in the cradle. While I'm in there and all that....
Refit the wheel arch liner, I prefer to use hand tools for light weight re-assembly as its just too easy to destroy these small fixings with a power tool.
Looking good double check everything is secure before re-fitting the wheel and torque to 140Nm once the tyre is back on the ground.
Repeat on other side.
Job done. Car was fine on test drive, ABS system was none the wiser for being disturbed.