Outer Limits 4x4 Board

I get a vibration noise from the rear end of my 85 drover when i reach 70km/h, under this speed it seems to be fine. can anyone shed some light on this for me as i have gotten the uni's replaced and it helped a tiny bit. but so far i cant think what it could be. anyone else had this happen to them?

i am unsure if it would be a diff related problem or wheel balance??
i heard a clunk clunk noise last night as i started to take off and would assume that was at the rear diff.

any advice/ideas would be very welcome.

cheers,

SmileySmoke

try going in reverse, change to first and drop the clutch, kinda like when ur bogged and trying to rock it out by changing 1st to reverse and back again....

if its a loud CLICK sound - that what i was getting, and karmic on these forums also had recently... one of the shafts around the spider gears in the diff develops about 10-15mm of play in it allowing the gears to miss teeth then suddenly jam in (hence the loud click)...

karmic and i got ours welded.

thanks alien i will try that at lunch if it doesnt clunk i would then assume that its the wheel balance or something as a few other guys mentioned that they have a bit of issues after a mud run and some mud being left on the inside of the rim.

hmmm. no clunk. just burnt a bit of clutch (soon to replace).
maybe i will book it in for a wheel balance and alignment just to be safe.. not sure what it could be.

might seem silly, but i also ages ago had vibrations in the rear at 90k's... i replaced rear tyres and all fixed... the sidewall on one of the tyres had a small lump in it (nothing bad, but enough to unbalance it)..

maybe run ur hand around the tyres sidewalls near the tread - might find an odd lump =)

tyres seem fine but one looks like it has thrown a weight. ( i bought the drover of a coppa and he didnt look after it,...)
the strange thing is when i reverse out of my driveway, it has a small slope and in the mornings when reversing it wont roll freely, it feels as if the brakes are held on a bit.. maybe this could be all related?

Is the tailshaft spline in good nick?
are the uni's "in phase", that is do the cross's line up,
have you been doing any circle work lately and clipped a curb, bending a rim (have some one drive behind you if you don't know how to messure it)
push up on the tranfer case output flange and the diff pinion flange, any excesive movement there?
also, the source of a vibration can be very hard to pick,
sometimes a noise from the front sounds like the rear, don't lock your self into only looking at the rear check the front as well.
peter.

i also posted a topic about having a wobby back end after having the diff welded...

turns out the ignition leads were corroded really badly, which meant it stuttered under load... new leads in and voila!

The tail shaft unis can sieze on one axis, without being obvious from the outside. This is more common with sagged suspension, as the unis dont get worked on both axis much. Its usually more difficult to reverse, and vibrations can result. Of course theres many possible reasons, but its worth checking the unis, especially the one at the diff end. Shaft needs to be unbolted at that end, then see if you can bend the unis both ways...It sounds like a problem I had pre suspension lift days. Another check (be careful) is after a longish drive, park it, and feel the unis, they can get very hot if siezed up, so be careful...extreme heat usually means a uni problem
Good Luck

christover

Mine shook because both my rear drive shaft unis were buggered, but u said you replaced yours so can't be that.

derelict_frog wrote:Mine shook because both my rear drive shaft unis were buggered, but u said you replaced yours so can't be that.

I should read more carefully before opening my typing finger
christover

christover - is all good i wont knock back any advice its worth a reminder. but yeh i got a mechanic to replace the unis. my old ones were so seized it snapped his bench vise in half haha yeh but he was happy as he got to buy himself a new hydraulic one.

the rims seem fine as i took them all off over the past week and sanded them back and cleaned them up then repainted (the noise was happening before this).

turns out the ignition leads were corroded really badly strange but i have new ones so nah.. plus it only occurs after i hit 70km+

are the uni's "in phase", that is do the cross's line up, well i hope the mechanic dude done it right! but it was doing it before the unis were replaced.. just alot more severe .

wheel alignment and balance should be the go. thats this weekend. reminds me.. i best book the little bugger in.

thanks for all the ideas guys! keep em coming

dont think i have updated this in a while..

heres what has been done so far:

* i have replaced all uni joints on all driveshafts.
* replaced gearbox mount as it was farked.
* replaced engine mounts (when first bought)
* full wheel alignment and balance..
* installed stereo to combat the noise

after all that the noise is still there.

the last thing for me to do is to replace my rear driveshaft and see how it goes.. i am still trying to source one over WA way so if anyone has one i would love to take it of your hands

i cant wait to get this noise/vibration sorted as it is driving me nuts. the stereo i installed drowns it out pretty well but still that isnt the best solution

cheers all.

Hi Smileysmoke,

Only briefly read the whole post, but it might be the rear wheel bearings?

I had a whirring/vibrating noise comming from the back of my car when i was driving over 40 ks. Turned out to be the left rear wheelbearing. Probably died from driving in too much water. The right rear wheelbearing died about 8 months later.

I could really hear the whirring when coasting down a road.

Hope it helps
Sting

sorry to take the topic over, but my diff has started to make a noise, i checked the oil it was dirty as, and it only makes a noise under acceleration, when coasting its dead silent, im going to weld it soon anyways but i was wondering if anyone else has had this problem, its noisy as heck, cant even have a conversation in the car.

hi sting.

thanks for the reply. yeh a few guys thought that but i was told that wheel bearings should be making a noise all the time if they are farked... could be wrong..?

beally may be the same thing man. changed your diff oil lately? if its that noisey then that sounds a tad worse.. mine is a bit better since changing the oil and new unis all round. oh and new rear brakes.. new drums and pads that is..

cheers.

ok problem ended up being the yokes not in phase on the driveshaft.
i was under the assumption that the mechanic knew what he was doing when he replaced the unis for me... not the case.
my bro and i checked the driveshaft last night and found that it was 20mm out .. lined it up properly and bolted it back in.. vibration is finally gone! so simple.. so yeh thanks all for your input.. cant believe it was so basic.

cheers,

SmileySmoke