Suspension Bolts/Nuts

[drewster99]

When installing coilovers, do people typically just reuse all the bolts and hardware or buy all new stuff? I have done it in the past where I just reused them all and everything was fine but a friend of mine just mentioned that you're supposed to buy new hardware. I'll be installing coilovers in the next few weeks and want to get it right.

Thanks!

[E82MSport]

According to the service manual there are a handful of suspension bolts that should be replaced but that's highly debated depending on who you talk to.

On the front -
1. Top mount nuts can be reused (the 3 that hold the strut to the body)
2. Top mount gaskets (get new, they're cheap)
3. Top mounts (replace depending on condition)
4. Swaybar links (replace depending on condition)
5. Brake wear indicator (only 1 on driver's side, will probably break when removing)
5. Caliper bracket bolts - reuse (I advise you remove the caliper and bracket as an assembly, do not remove the 2 allen bolts holding the caliper to the bracket)
6. Rotor retaining screw (reuse if not damaged, apply anti-seize when installing hand tight)
7. ABS sensor allen bolt - reuse
8. Headlight level arm (unclip from control arm, do not remove nut)
9. Spindle pinch bolt that holds the strut - reuse
10. Lower control arm bolts (I've reused several times but have replaced once - remember they are torque to yield stretch bolts)

Rear suspension -
1. Upper shock mount (I would replace all the hardware)
2. Lower shock mount (unless the mount is bad there's no reason to replace anything)
3. New shocks should have new nuts for top and bottom
4. Swaybar links (replace depending on condition)
5. Lower control arm bolts - reuse
6. Lower and upper spring rubber (replace depending on condition)

There are kits out there that have everything you need when replacing suspension but they are expensive and most likely the majority of the hardware doesn't need replacing.

Here's the kit for ECS for example -
https://www.ecstuning.com/BMW-E82-13...its/ES2586384/

[Suprgnat]

Originally Posted by E82MSport

According to the service manual there are a handful of suspension bolts that should be replaced but that's highly debated depending on who you talk to.

I think the only people that debate whether the torque-to-yield fasteners in our BMWs should be replaced are the people that didn't for whatever reason. Most of the time you'll be just fine...

[drewster99]

Originally Posted by E82MSport

According to the service manual there are a handful of suspension bolts that should be replaced but that's highly debated depending on who you talk to.

On the front -
1. Top mount nuts can be reused (the 3 that hold the strut to the body)
2. Top mount gaskets (get new, they're cheap)
3. Top mounts (replace depending on condition)
4. Swaybar links (replace depending on condition)
5. Brake wear indicator (only 1 on driver's side, will probably break when removing)
5. Caliper bracket bolts - reuse (I advise you remove the caliper and bracket as an assembly, do not remove the 2 allen bolts holding the caliper to the bracket)
6. Rotor retaining screw (reuse if not damaged, apply anti-seize when installing hand tight)
7. ABS sensor allen bolt - reuse
8. Headlight level arm (unclip from control arm, do not remove nut)
9. Spindle pinch bolt that holds the strut - reuse
10. Lower control arm bolts (I've reused several times but have replaced once - remember they are torque to yield stretch bolts)

Rear suspension -
1. Upper shock mount (I would replace all the hardware)
2. Lower shock mount (unless the mount is bad there's no reason to replace anything)
3. New shocks should have new nuts for top and bottom
4. Swaybar links (replace depending on condition)
5. Lower control arm bolts - reuse
6. Lower and upper spring rubber (replace depending on condition)

There are kits out there that have everything you need when replacing suspension but they are expensive and most likely the majority of the hardware doesn't need replacing.

Here's the kit for ECS for example -
https://www.ecstuning.com/BMW-E82-13...its/ES2586384/

Perfect, thank you!

[houtan]

For the torque to yield bolts, I reuse once and then replace. And I remove reinstall with hand tools vice air tools to minimize the amount of impact/load on the bolt.

[tracer bullet]

Originally Posted by houtan

For the torque to yield bolts, I reuse once and then replace.

You can get away with it, but keep in mind after it's actually been used as a TTY bolt, re-using it means you are using a fundamentally different bolt.

[dojk]

What about the reinforcement plates and rubber sealing grommets?

[John_01]

If using NEW bolts, the mechanic 'should' follow the tightening procedure in the BMW manuals.
I'm not sure if many mechanics actually do that - They are probably scared of breaking bolts that are supposed to be torqued to yield.

[juld0zer]

Also beware of reusing the egg shaped nuts. This is where undoing fasteners using hand tools is better because you will be able to tell if it's an egg shaped nut or or if has threadlocker for example.

The pinch bolt which clamps the shock to the knuckle is not a mandatory replacement item apparently, but its egg shaped lock nut must be replaced.

[dojk]

There seem to a washer gasket and a dust protection collar sandwiched between the front upper shock mount and the upper spring plate. Do I need to change those as well?

[asbrr]

Originally Posted by dojk

There seem to a washer gasket and a dust protection collar sandwiched between the front upper shock mount and the upper spring plate. Do I need to change those as well?

If parts supply is not a problem, these are cheap parts so why not just replace...

[dojk]

Hi all,

any torque figures to put the car back together?