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vinnY
14-08-2008, 05:40 PM
are there any tell tail signs of when the drive shaft bearings fail? if that what their called..

talkin' about these babies:
http://i16.photobucket.com/albums/b35/Paul_K_1985/CV%20Boots/DSC02639.jpg
thanks for the pic paul1985!

little back story;
couple months back driving along and my wheel goes all wobbily, think damn must have a flat tyre.
pull over to a side street, all tyres are fine and properly inflated.
get back in and move slowly, seemed that with every 360o rotation of the wheels i'd hear a knock coming from the front coupled with the sensation of a wobbling steering wheel.
baby it about 50m down the road and the wobbily steering wheel stops and the sound is no longer there.

takes it home and throw it on stands for inspection and nothing seems out of place, nothing seem missing and theres no extra bits which shouldn't be there.
took out the drive shafts and had a look at them, appears to be visually fine on the outside so i pop them back in.
check all my suspension components front and rear and everything seems to be in order, bolted up and nothing out of place.

now it's been fine ever since, no more knocking sound but i do get the occasional steering wheel wobble sensation for a sec.
generally happens around the 40-60km/h mark while accelerating in second or third and sometimes at high speeds ~110km/h while travelling on the freeway.

could this be a sign of a failed drive shaft bearing?
or something else more or less serious?
not sure on the age of the current ones, should i just rip off the boot and replace them anyway?

Limbo
15-08-2008, 10:13 AM
look like your wheel bearings aren't they?

Anyway, if you've ripped them all apart you might as well buy new ones. They are about $50 for each side last time i looked. Can't rem but it was from mekong spares.

Only way you know they are going if they get noisy or the pop out in bits. The reason is that the unit is sealed and usually burn out the balls in them when they get contaminated or excessive wear. I've had to change a few sets in Toyotas as they have this problem alot. Usually you only get bearing issues after 100k or so.

Just one thing to be sure of when you install them or they will fail fast.
1) make sure the area is really clean
2) make sure you only use their grease that they give you. Usually some white lithium grease & make sure you put a good amount of it on.
3) try to reassemble without getting any dirt, dust or grease on it.

Limbo
15-08-2008, 10:14 AM
P.S wobbling are usually the bushes. Stuffed bearings usually make noise before they start to wobble. Look for worn bushings or start replacing bushing. New bushings are always a good mod anyway on an older car

vinnY
15-08-2008, 10:29 AM
yeah could be bushes.. going to be replacing quite a few so i'll do that before sussing out the guts of my driveshafts :) thanks for the info man

ECU-MAN
18-08-2008, 09:30 AM
wobbling at high speeds is a sign of either worn bearings in the CV or not enough CV grease.

make sure you can rotate the CV freely and it should not bind at all.

BRacinU
22-08-2008, 12:27 PM
Agree if u already hv em out u may as well change em, doesnt sound like bearings though, ususally get more signs if the bearings are going like clicking and even grinding especially when turning or at full lock. U can inspect the bearings on the car, take the boots off, turn the steering to full lock and watch the ball-bearings, they should drop cleanly as you turn the wheel, if they stick togeather prob time for a change.
Also agree about the bushes, worn bushes make floaty steering, most likely bushes on the LCA's. You can check jack the car up until the wheel is able to free spin grab the wheel and pull it towards you firmly, it shouldnt move.

BRacinU
22-08-2008, 12:41 PM
PS also for got to mention the bump stops on the top of the strut (Strut tops), if they wear, the whole strut will wobble.

ECU-MAN
22-08-2008, 12:45 PM
Agree if u already hv em out u may as well change em, doesnt sound like bearings though, ususally get more signs if the bearings are going like clicking and even grinding especially when turning or at full lock. U can inspect the bearings on the car, take the boots off, turn the steering to full lock and watch the ball-bearings, they should drop cleanly as you turn the wheel, if they stick togeather prob time for a change.
Also agree about the bushes, worn bushes make floaty steering, most likely bushes on the LCA's. You can check jack the car up until the wheel is able to free spin grab the wheel and pull it towards you firmly, it shouldnt move.

Vinny is refeering to the inner CV joint
your refeering to the outer CV joint, Diagnostics is a bit different

vinnY
22-08-2008, 12:50 PM
PS also for got to mention the bump stops on the top of the strut, if they wear, the whole strut will wobble.

?!??! i remember one of mine are pretty crap.. whats the reason behind this though? if you're travelling in a straight line it shouldn't affect it should it?

BRacinU
22-08-2008, 01:37 PM
If they wear the strut will be loose it will cause wear on other parts, like uneven/increased Tyres wear! Wheels designed only move in at round and round in a clock-like motion horozontal movement increases wear and decreases drivability.
Driving wont feel as firm.

BRacinU
22-08-2008, 01:38 PM
Vinny is refeering to the inner CV joint
your refeering to the outer CV joint, Diagnostics is a bit different

Yes thats true, but outer bearings tend to wear faster/often. Plus to me sounds more like bushes anyway.

Paul1985
23-08-2008, 12:54 AM
Those are the bearings in the CV.

When you had them out, did you check if they could spin freely as ECU-MAN mentioned?

Check your ball joints aswell.

Is it only on turning left or right, or turning both ways?

Target the side, then check all the suspension bushes on that side aswell as the ball joints, when the car is on stands/hoist turn the driveshaft by hand, does it turn easily??? any noises???

Quiet often once you target the side and have the car in the air, the area of the problem will become obvious.

Paul1985
23-08-2008, 12:56 AM
btw. np's about the pic, there are easier ways to change CV boots than that guide i made though if you were following it. That was one of my first ever DIY's and i was still doing a pre-apprenticeship course at the time.

vinnY
23-08-2008, 01:02 AM
will check it out soon, having bits and pieces out to change the bushes so i'll see if theres anything funny about it then

just been too freaking cold in sydney lately to feel like doing any productive work at all:(