Bizarre issue with droplinks breaking / coming loose

[Kellerman]

Morning all,

My buddy has a BMW 1 series, fitted with the M3 V8 engine (hilarious combo) and purchased brand new BC coilovers. These came with droplinks, which stripped the threads when tightened. He's a trained mechanic so wasn't going full send with the impact gun. He ordered a replacement set of droplinks, tightened the nylocs up by hand and torque wrenched them. These then came loose!

He's then ordered some generic adjustable droplinks, again these have worked loose.

It's baffled us both. Any ideas what's going on here? Some bizarre resonance from the engine, going via the solid topmounts?

Thankyou

[Dave.]

Is there enough thread to double-nut them?

[stevieturbo]

Kellerman said:

Morning all,

Any ideas what's going on here? Some bizarre resonance from the engine, going via the solid topmounts?

Thankyou

I would say more likely user error than that.

But as we cannot see what is going on, how things are being installed etc etc...impossible to say

I can't recall ever where I've seen a nyloc nut just randomly come loose.

[GreenV8S]

Either the fitter isn't doing them up tight enough, or there is some torque or flex being applied to them which is forcing them to loosen.

A paint stick would at least tell you whether the nut is backing off or the thread is stretching.

[E-bmw]

Never heard of drop links working loose before, has he checked they & the coilovers are installed correctly as if they weren't aligned it could cause what GV8 says?

They should be pretty vertical & 90 degrees to the ARB or something close so that they do not "bind" as the suspension operates.

[Mark Turmell]

On my VW van the drop links worked loose twice, turns out the guy was torqueing them up to the correct spec but not doing the 45º rotation, is that the same on a Beemer?

[Kellerman]

Thankyou all - some good replies there. Will try all of the above on the next set.

(good time to take out shares in droplink manufacturers!)