E36 m3 vibration HELP!!!!

[bornlucky1]

I have posted this in the m3 section also but thought that maybe it was something all e36 can suffer from so put it here aswell,

I hope you guys can help, today me and my dad dug out our E36 m3 evo from the back of the garage to start getting it ready for this years track- days.
After a quick fluid check and tyre pressure check i decided that before we service it we better get the oil heated up by taking it for a country blast
(great excuse eh), when our speed rose to around 50mph there was this terrible vibration. First thought was balance weights have fallen of or buckled tyre,
so we drove straight to our tyre dealer and got the wheels balanced while i watched, the wheels were very slightly out (all less than 20g) but he balanced them to perfect 0-0g (I used to work with this guy and he knows how pernickety I am!) also all tyres/wheels were perfectly round with no flatspots.

Up the nearest m/way and the vibration is still there!
so we went straight to my work and put the car on to the ramp and checked, w/bearings, balljoints, bushes but everything seems to be nice and tight.
The vibration is really bad and is coming right through our seats and steering wheel- it never did this before its winter sleep!

Any ideas before i start pulling of the gearbox and diff?:cry:
Thanks in advance , Gary.

p.s, great forum you guys have here i just wish id found it sooner.:)

[E36 Phantom]

E36 M3 Evo???

SO JEALOUS!


Anyway......if you never had them before winter, I'd wager the tires must have some sort of flatspot, even though the tire guy says no. If they're Continentals, I can all but guarantee it. If they're other brands, it's still relatively likely. Just how long was it sitting?

Also, is the vibration coming more through the wheel or the seats? If it's more in the body/seats than the steering wheel, check your driveshaft. Perhaps it's loosening up or your flex disc is bad. Front or back of the car?

Did you check the rear trailing arm bushings?

[bornlucky1]

We got a lever and checked all the bushes were tight - all are in good condition.
Never thought about the propshaft though - is there a weekness there?
Thanks for replying.

[bornlucky1]

Oh and it starts at the wheel first but as you get faster it seems to come from under the
car- quite violently!!
All tyres are definately fine as we checked for high / low spots when it was spinning on the balancer with the hood up.
thanks again. Gary

[E36 Phantom]

The flex disc (aka guido) is designed to reduce vibrations in the DS. It could be failing - that's a known weakness. Search it and you'll see lots of DIYs. The DIYs will have pics and show you how to look for failure signs. Any other DS problems would be anomalies, but that doesn't mean it's not possible.

[bornlucky1]

Thanks a lot, will check the propshaft first thing tomorrow
and let you know.:thumbup: