Vibration on quick left cornering

[Coops Mk1]

copied post from other forums, any input greatly appreciated as am about ready to bin the whole damn car....

Right am about to go for my 4th drivers side driveshaft tomorrow

my question is, why does it keep vibrating?

the story goes, i lowered the car after the engine rebuild and changed my driveshafts both sides at the same time (cv boots knackered, so figured better safe than sorry and go for re-furbs from renault) and there was a massive vibration through the car on left turns. i changed wheel bearing that side, no difference, so eventually it was pinned down to shaft

shaft was changed again, was fine i think for ages, but now having fitted my r888 and really pushing it round corners, the vibration is back again, this time its whilst pushing a lot harder, and tight corners only pretty much but its there and its bad when it happens.

now i talked to my dads mechanic this weekend and he thinks it may be because the car is too low, so when the suspension compresses aswell as hubs already being higher than diff, the shafts outer cv joint is at too much of an angle and vibrates. is this possible? how come it hasnt happened to anyone else? mines low but there are lower cars out there so what do you guys think?

also why only this side, i mean i realise that the engine and me are on that side so its got more weight to push down, but still, cornering the other way at any speed is fine, no matter how hard i push, its only left turns where it struggles

i'm really hoping its just another dodgy shaft, but any advice/experience on this would be much appreciated!

sorry for the ramble

cheers

Ben

free bump

still bloody doing it, new shaft, so its not the shaft itself, or maybe it is but its because the shaft geometry is out?

noticed today that looking top down through the engine bay the hubs are behind the output shafts of the gearbox, so the shafts are naturally swept backwards, is that right?

also if i undo the hub nut, should i then be able to move the shaft in and out of the cv joints/hub spline both ways?as in slack enough to extend and shorten the length of the shaft? and should this be possible with weight on the wheels, or only when jacked up?

cheers

Ben

arb fouls wishbones, but does that on both sides, and did it on my old valver aswell when it was this low, spose cud be that, am raising it this week to see

could it be diff bearings in the box? i wud of thought if it was there wud be more symptoms, like cornering both ways etc?

rollpin is new :wink:

 

[Russ_16v]

i had this problem years ago mate and it turned out it was because i had a non genuine shaft,and it was half an inch to short, mine was the drivers side shaft just like yours,so just to clarify are you using genuine renault shafts?

if so get under the car and grab the shaft and see if you can move it at all,a tiny bit of movement is ok but il bet yours will have more because this sounds just like my problem


hope that helps

 

[Mark One]

Have you done the ball joints yet?

As in the bottom arm ball joints. Cheap, and I would suspect thats your problem because you seen to have tried everything else.
The car too low thing is not it, im pretty sure. (unless it's scrubbage)

 

[Mark One]

if not, do Suspension top mounts mate.

 

[Coops Mk1]

theres not much movement mate, half a cm or so with hub nut off, none atall with hubnut done up obviously,lol

they are both gen shafts

 

[Coops Mk1]

nah not scrubbage, cant see anything on that,no evidence on any components

wishbones bushes, wishbones and ball joints are all new and track rod ends are fine also

i'll try top mounts aswell

 

[Russ_16v]

engine mounts mate?

 

[Mark One]

I reckon top mounts will solve it

 

[Coops Mk1]

engine mounts are all new as well lol, i've tried most stuff!hehe

i'll do the top mounts this week and see how she goes

 

[Linsen]

Sounds just like my problem. Same side of the car, but mine is LHD, so it's got nothing to do with weight distribution. Also mine's done this on standard suspension and on pro lines, so lowering is not the problem either. My top mounts are brand new and the problem still persists. Apparantely my left drive shaft sleeve is knackered, but since the vibration only occurs under very hard left cornering, I doubt that's the reason.

Check out this thread I posted a while ago. Plimsole apparantly has changed all engine mounts and it seems that more or less cured it.

 

[Coops Mk1]

all my engine mounts are already new, so cant be that, its a pain in the arse this

driveshafts are new aswell

 

[Plimsole]

As I said in the post that Linsen refers to, changing the engine mounts made the noise a million times better... but I could still just about feel it. When you changed the driveshaft on the drivers side did you change the intermediate bearing on the shaft? I still strongly suspect it is something to do with this...

I have changed or tried: Driveshafts (both sides), lower wishbone ball joint (drivers side), wheel bearings (drivers side and both rear), top mount washer fix thing, new tyres all round, new engine mounts all round, swapped alloys front to rear, cut away excess wheelarch trim all round, some power steering pipe that Reno thought would fix it, plugged it into a laptop whilst cornering to see if it was an ABS fault.

Its been into some reputable and not so reputable places to be looked at (Eurocarcare were good, Hillpower were good, Renault Derby not so good) with no success in finding the problem.

The only thing from the long list above to make any noticable difference was when I changed the two gearbox end engine mounts.

 

[Coops Mk1]

bugger

mines a mk1 so no abs and driveshaft is one piece mate, no inter bearing or whatever ur on about, or if you mean inner cv joint on that side thats integral to the shaft then yes that was changed lol

i adjusted my camber tonight and doesnt seem so bad, so i need to grind hubs to further reduce camber and see how it goes

 

[Linsen]

Are you saying you're going towards positive on camber? I am going to have my camber set to -1.5° to -2° soon and I was actually hoping that might reduce the judder/vibration...

 

[Mark One]

and it's ONLY on cornering? couldnt be wheel balancing or anything glaring obvious?

 

[Coops Mk1]

yeah towards pos, run around 2-3 degree neg atm

 

[Linsen]

So out the window goes my hope of reducing the vibration by going towards more negative camber. I'm on standard atm.

 

[Plimsole]

Yeah, sorry Point8 but I forgot to put down that the tracking has been done a few times, and all the wheels have been balanced with the new tyres.

On my car I have a short stub axle coming straight out of the gearbox on the drivers side, then there is a bearing (the intermediate one I talk about) connected to the back of the engine (to support the end of the stub axle), then there is the normal CV joint and driveshaft arrangement.

I'd be surprised if you didn't have some sort of intermediate bearing, unless your gearbox is central. I think the idea of the stub axle is so that the length of the driveshafts (from one CV joint to the other) is the same, I think to stop torque steer. But no doubt someone wil correct me

 

[Coops Mk1]

the output shaft on that side come straight out the box and the shaft connects to that mate on mk 1, nothing on the engine block or out, the inner cv joint is integral to the shaft which fits with a spline over the output shaft from the box

 

[evilb66]

i have been battling with this problem for a couple of years.
i have been down the same path as plimsole and wasted lots of money tyring to find faulty bits.
I agree that the engine mounts seem to be the problem.
try an experiment..... in the drivers side upper engine mount, there is space for the engine to move sideways. try stacking a few washers on top of each other, wrapping in tape, and jamming them in to stop the sideways movement. then try your hard left cornering.

I had a huge reduction in this clunking noise when i did this, prompting me to order some of the ktec reinforced mounts.

the other thing i have done that helped was to reinforce my subframe, where the lower wishbone attaches. the holes in the subframe, especially the rearmost hole on the drivers side (both sides actually, rearmost hole) had enlarged massively, causing the wishbone to move in and out, under cornering and braking load.
do a search for subframe. one of the other aussie forum members has posted about it.
i fixed mine by welding on some high tensile washers. cost about 50p plus welding.

 

[Dave..]

saw your mk1 on friday i think it was, wondered why its not been there since. Take it you've tried all the obvious like brake callipers/wheels rubbing? Don't suppose you could take any videos of said vibration? might give some one more clues (if you need anyone to film *hint*)