E39 M5 Elusive Vibration...

[belleair302]

Also get the centre tie rod checked.

[derestrictor]

belleair302 said:

That E34 would have been a much better acqusition than spending cash on an E39....you cannot beat a handmade, low volume limited edition car.

Ooh, I dunno, there's still an illicit thrill in smiting VW CGTs and their ilk! (Not to mention pesky E46 320d bods who are genuinely stereotypical and clueless in equal measure!)

[jeremyc]

Last Friday derestrictor said:

The old dear is in again on Monday. We'll get there.

Any news, your Lordship?

[derestrictor]

Hello Jesmondacles of The Lower Palatine.

Old girl in yesterday for one last go, thence to the specialists for which referencing I'm grateful to Messrs ASBO and V1xpy.

Drop links, done; thrust arm (bushes), done; control arms being done; sub frame mounts being done; gearbox mounts being done and propshaft 'doughnut' bush being done (where 'done' = checked and replaced if necessary.)

If none of this works then (a) I'll resume my affectation with Scottihs distilleries and (b) try some other wheels up front.

Charlie's man suggested something to do with the brakes but I'll look at that one via said specialist if all else fails.

Biff may have hated manure but I hate untraceable vibrations!

[jeremyc]

It'll be the newest E39 out there once you've replaced all of those bits.

Will the old girl be out for a gallop at Brunters, or is the outing reserved for those limited to two entry portals only?

[derestrictor]

Should be sufficient loafment of the idle hand come the day so yes, a jaunt below the Capricorn of Nose Bleed would do the old bint no harm at all. Trust you'll be 3ing of GT?

[jeremyc]

derestrictor said:

Trust you'll be 3ing of GT?

In the absence of people rushing to offer me the keys to their hypercars for the day it would be rude for me not to bring Mr Orange.

[9mm]

have you checked the rear arb brackets?

[dazren]

ASBO said:

Der,

I am experiencing a similar vibration at ~60mph in the old girl which I have been told is the prop-shaft 'doughnut' after the wheels were balanced etc.

Rumour has it, we have a winner. Top work ASBO.

Don't think he's collected the car yet though.

[derestrictor]

Usual brand of not quite Lexian service: Von ASBO's excellent diagnosis was acknowledged by the dealership yesterday in a moment of self-confessed, Homer 'doh-ness,' propshaft doughnut duly ordered and yours truly had been looking forward to a paragon of moorland schnleted solidity only to be told several times that bits and pieces were lying around and eventually, some clips which should have accompanied the parts hadn't been in the pack and...well, you know BS when you smell it.

Even so, I've been assured it will be ready on the morrow so will be expecting it's delivery at some point. Thence to Fearnsport for the brake saga: assuming the vibe itself is done for if not, the great man can sort that, too.

RS6 for sub £25k, anyone?

[belleair302]

I believe JeremyC may well be in the market for a faster Audi than the Blue Devil. Maybe a new RS6 tickles his tastebuds as a fast tow car...although no chance of using that third pedal.

What brake kit are you having installed, AP, Mov'it, Stoptech, or something else?

[derestrictor]

Squire, it's already on it's 2nd AP 6 pot system (up front, std at t'rear) which have been a model of utter dross to date.

Lord ASBO's researchers have cited the works of renowned Beemer race fettlist, Jeff Steel whose theory on this surrounds the relative lack of floating (if any, in extreme circs) for these discs caused by heat expansion relative to the bell housings.

Apparently, the boltholes may need reboring... A Farewell To Vibrations. We shall see - this is certainly a job for our man at Silverstone.

[belleair302]

Mov'it are the way to go.....and this is no idle boast. Used extensively by 'ring addicts and put on some of the best modified cars around. Search the M5board forums and they get nothing but praise....much better quality than AP.

[derestrictor]

Do they get used by M3 CSL bods? Think I saw one shod accordingly at the dealer this week.

I'll persevere with the APs for alap but give these a whirl, on your recce, when they've expired. Cheers.

[belleair302]

M5 owners use them (e39), Porsche owners too and anybody who is very serious about brake kits. The link below will explain who these guys are and what they do....more than one can imagine and with some first class engineering too.

http://www.movit-scandinavia.com/en/products_faq.a...

or

http://movitbrakes.com/rahmen/bmw.htm

Edited by belleair302 on Friday 29th February 13:54

[derestrictor]

Thanks.

Mine will be 'assessed' post VMax and whatever transpires, their replacements, sooner or later, will be these.

[Brendan Lennon]

I’ve tried Movit and the pedal was way too soft, they’re porsche specific with larger than normal sized piston which affect the front/rear braking bias, Stoptech are best for the E39 M5.

Sounds like your diff is on the way out Der, similar symptoms here, couldn’t pinpoint the exact location as it seemed to travel up the drivetrain, got louder & louder, the whole car / windows would vibrate ever so slightly, until it eventually exploded in dramatic fashion one day

[belleair302]

Funny that, I have tried an E39 with Stoptech brakes and they felt strained after half a dozen high speed runs and left the car feeling under equipped when hitting the anchors. The Movit kits are very well engineered and handle the weight of the E39 beautifully. It is worth doing both front and rear if serious about Vmax and numerous high speed trackdays....ie not Brands Hatch.

[derestrictor]

belleair302 said:

It is worth doing both front and rear if serious about Vmax...

Er...

Well the propshaft doughnut was knackered and replaced: I'd say it has made a big difference, especially in the sub 70 zones although a trace wobble can still be suffered - albeit less frequently - when obeying m-way speed limits. Ish. There is also still, a distant and very low level 'knock' somewhere in the bowells when traversing certain ridged imperfections - this is a real swine because it is something I am 'tuned' into - the average techy simply cannot fathom this one...

Will ask about the diff but nobody's suggested that hitherto and all bets are leviatating towards a disc imperfection and resultant troubled relationship between caliper(s) and/or bell housing.

My problem is that I am a perfectionist and I'm sure 95% of folk wouldn't notice but I know it's slightly off and like the Spartan King, compromise is not really on the menu.

[derestrictor]

Ok, dowager update...

+ve news, by the sounds of it.

Andy Fearns has been kindly teaching the roundabouts of Bicester the meaning of Herman Does Oxon this last week and in conclusion has pretty much stripped and rebuilt the brakes.

The AP discs weren't warped but a coagulation of fetid, socialist, road bourne detrius had caked the surface so severely that lunarscape rather than mill pond described the interface suffered when pad made contact, a surefire wobble guarantor.

He changed the disc holding bells and the seals (12 off) in the calipers where seizing was an issue. (This was a bit of a prob astern, too, so these have been attended accordingly.)

A softer compound pad has been inserted and first reports are both wholesome and smeared of baby lotion. Let's just hope trafpol are in the correct frame of mind for the post collection journey...

Von Fearns has also concluded that the front shocks and strut tops need replacing which might account for a low level, barely perceptible but 'hone-inable' ocassional knocking from the lower decks so I'll get that seen to by the dealer next week when the PDC sensors are replaced.

It would've been more cost effective to relaunch Cornwall's tin mining industry but common sense went some way west of wonder a long time ago.


Onward...