Metal chirping sound from back

[thebishop]

Got a p85d which has an intermittent metal chirping sound from back left - wheel bearing or something with brakes?

most noticeable at low,speeds (<20mph) and comes and goes.
I’ve scheduled (and rescheduled) service a few times as it comes and of course goes away just the few days before the service slot. Then it comes back. Starting to suspect gremlins.

The brake pads were replaced in 2018 and it’s not obviously related to braking (was thinking either brake pistons needed lube or wheel bearing going bad) - any guesses or ideas? DU?

 

[Russell]

Are lugnuts tight?

 

[thebishop]

That was a great question. Just went out to check, and the tool doesn’t fit (should be 21mm, but some of the nuts are deformed from the guys replacing the wheels...) - I have the old nuts without plastic covers. 23mm is way too big and I don’t have a 22mm.

 

[Russell]

Those older lug nuts deform very easily.

Some of us have replaced them with Gorilla lug nut 61148CX or 66148DX. Gorilla Automotive Products

 

[thebishop]

Thanks, will see if I can get those here, otherwise I’ll just pick up the 2gen Tesla ones with plastic caps... :-/

 

[agloutney]

What you’re experiencing could be a lack of lube in your wheel hub where it meets the axel spline. They don’t seem to put enough molybdenum grease when it’s assembled and they start to corrode which further displaces the grease. They can remove your hub and clean it out thoroughly then re grease it. Make sure they get it right deep into the hub and you’ll be good to go.

 

[thebishop]

Thanks! Will discuss that!