[dleccord]

i'm replacing my front and rear struts/springs which means loosening nuts from control arms, end links, strut hats, etc. are there any bolts/nuts i have to buy from dealer? i recall having to use new nuts for the front m3 arms. thanks in advance!

[mweisdorfer]

Originally Posted by dleccord

i'm replacing my front and rear struts/springs which means loosening nuts from control arms, end links, strut hats, etc. are there any bolts/nuts i have to buy from dealer? i recall having to use new nuts for the front m3 arms. thanks in advance!

It depends if they are aluminum or not. Also, where you live. If you live in the rust belt (Midwest), your better off getting new bolts and nuts etc.

Any bolt with blue paint on it, can not be used again and therefore must be replaced.

I'd never buy nuts & bolts from a dealer. Better off buying them from ECS or FCP Euro.

Go to BMWfans.info and get the part numbers.

[whyzee125]

You can reuse some but you should replace them to avoid what I'm going through. My control arm bolt won't come out because it stripped in that stupid one time use nut so I'm having to grind the whole thing off.

[PhaseP]

If you go by the shop manual 99% of the bolts and nuts on the suspension are to be replaced by new ones. If you can afford it is better to go with new ones. The nuts especially are self locking type recommended to be one time use.

[Austin LeNomad]

I tend to keep the old bolts off the BMW in case of some emergency, and I have amassed a huge amount because it does seem that other than the screws that hold the underplastic, everything seems to be aluminum and need replacing. I probably have over 100 bolts at this point that have been replaced.

[dleccord]

front strut installation, im thinking rears too, requires loosening the bolts and nuts on control arms so you can swing the hub or lower control arms (rear) downward to remove the struts and springs. if i'm just loosening, does this mean i'm still "removing" and that will require replacing bolts/nuts of the control arms where it mounts to the subframe?

[juld0zer]

It's been covered before but as earlier stated, most suspension fasteners are single use only, particularly the lock nuts.

The reason is debatable but it can be any one of these or a combo of both:
- Self locking nut which gets ruined upon disassembly. ie the locking function is impaired with repeat usage
- Stretch bolt which usually has a torque plus angle spec
- Anti-corrosion ZNS coating gets abraded upon disassembly

There are NO aluminium bolts used in suspension assemblies.

Having said all the above, if you dont have the torque specs and just tighten everything FT then i guess the choice is yours. Fasteners do inflate the cost of repairs and mods by a fair bit. For all my customer cars i follow the book so to speak. For my own car i will replace where specified and when i have time to wait for parts to arrive.