reason to belive shaking is rear wheels

[Wilson]

I believe my rear wheels are causing my car to shake over 80mph, main reasons quote below, but this morning I noticed that as I accelerate the shake is worse, and as I back of the shake disappears, if I cruise at set speed the shake is there but not as bad.

Which makes me think its the rear wheels because of the weight transfer when accelerating decelerating etc...

Would this make sense to anyone else or am I talking rubbish!!!???

Below quoted from another topic
http://www.e30zone.co.uk/modules.php?na ... ic&t=10378

Honestly wanted to do that, and possibly have the lips polished / diamond cut too.... would look good. I like the rims on my car but there is a few problems with them ---

1, two off the wheels are dented on the inside, one quite badly the other not so bad (Could be causing my 80mph shake)

2, only two of the wheels are actually mims, I dont know what the other two are!!!, they are very slightly different, they dont have mim stamped on them, one type has sharper edges on the spokes, and one set has a lip around the four bolt holes, while the others are flush.

3, two of them have the wrong bore size (rears) they are too big, which makes it almost impossible to centre the wheel on the hub without the spacer thingys (are they called spigots?) (Could also be causing my 80mph shake)

[Jhonno]

check how tight your wheel nuts are!!

[sabrje]

I had something similar - turned out to be a bulge on the inside of the rear tyre. I only worked out what it was when the tyre blew out at 60 though

[Wilson]

definatly tight, which should centre the wheels on the hub, as I tightened them bit at a time loosened etc etc... definately tight!!!

[E30BeemerLad]

Wilson - if you have aftermarket alloys fitted, have you got ring spacers that sit on the hub to make sure the wheel is properly centered when you put the wheel on?

Don't know if vibration etc from the rear end could be caused by a propshaft being out of balance or any problems with bearings? Someone else with a bit more tech know how may do a better job of diagnosing that I have! Are there any noises from the diff?

[Wilson]

Wilson - if you have aftermarket alloys fitted, have you got ring spacers that sit on the hub to make sure the wheel is properly centered when you put the wheel on?

No.. thats the point... the centre bores on the wheels are to big for the hubs.. that must be 99% what the shaking is... but why only shake over 80mph... I'd have thought if the wheels aren't centre you would feel it at any speed!!??

[E30BeemerLad]

apologies wilson - was being a prat and not reading all of your post and the bit you had pasted in

don't know what the deal is with 80mph being the trigger point. They will be vibrating at a lower speed, but it will just be as the speed increases and therefore the frequency of the vibration, it becomes more noticeable.

on mine there are some little green rings that fit into the centre of the alloy and make sure that when the wheel is put onto the hub, the centre where the large nut is fits exactly true with the wheel.

Mind you, I too have vibration at 80mph, but it is coming through the steering wheel. It used to be more severe and come on at 50-60 but since changing track control arms it has disappeared and i'm left with a more gentle wabble at 80. Need my wheels balancing properly first before I start looking to what the problem is.

Sorry - i am probably not being much help banging on about my own foibles~!

[Wilson]

No worries... track controls arms etc were done previously, I have no steering wheel shake just car shake from the back... hoping it is the odd fitting wheels and not prop/diff etc!!!

[johno]

i also have a shake in rear end turns out my nearside wheel is buckled also has worn my tyrer and i now think its not doing my bearing some damage as its started a droning noise

[JAMZ]

Sry didnt read all posts but my advice:

Swap yer front wheels for yer rear to see if it stops,then you can isolate it a bit better..

take yer wheels to a DECENT place where you can get em looked at to see if there buckled..alloys buckle with ease if driven over pot holes etc etc alot..

if their buckled you might be able to tell just by spinning yer wheels jacked up,but personally it on a balance machine and give it a whirl..thats how i found out that ALL 4 of my wheels were buckled and were producing the same symptons as youve quoted..

Wheel spacers is a viable cause too...

Vibration with no noice asociated is probably these kinds of things..

alot of people will say Prop-shaft out of balance but id put my money on buckled alloys

Carl

[psychochild187]

it only does it at 80mph from resinant frequency
as it vibrates u dont feel it you go faster and still dont feel it untill 80 hits and then it give all out and wobbles the hell out of you , get past a 100 and it might disappear , maybe hit 130 and it might come back!


and my golf wheels have all got bigger bores and dont fit properly and do this symtem

i can prove its them buy putting my wheels on in a certan way that makes them site in the center ! then no shaking!