Whats happened ? Diff explode ?

Had a bit of a grumble/rumble/noise from underneath creep in the past few weeks, just in higher revs or when accelerating form say 55mph towards 70, but i rarley rev it hard anyway and mostly cruise around 60 2100rpm sort of go, and would stop if you let of the gas

presumed it was the diff ? mate was getting it in this weekend to look at it, check/change the fluids etc

but left for work today, got on motorway, it started to get a bit louder/more of a rumble/vibrating, i was thinking this doesnt sound good..then clunk clang clunk break up sort of sound from underneath, i put in neutral went in to the hard shoulder and shat myself , it was ticking over fine, revved up ok

i had a look underneath with a torch, all looked ok from a quick look but was dark, and what do i do ,call breakdown, call work ,what

so...i sat there for a min, revved it, thought il see... and it movbed ok, i creeped along hard shoulder....and just carried on basicly... drove it 35 odd miles nervously, but it was SMOOTH !! totaly smooth, no rumble although took it easy and nervously, but it felt nicer than it has in a few weeks


so whats happened ????? what do i do next ???? is it safe to drive ??

has a diff exploded and its now not running on that diff ? (just a guess)

im 45 miles from home at work, and got work tomorrow

Sounds like a UJ to me, checked the VCU lately.

whats the uj ? and vcu ? how do you check ? i have no idea about this sort of stuff

whats does it mean has happend if it was rumbling,but is now quiet and drives nice still ???v i dont get it

also whats the rough cost to put it right and whats involved and parts needed etc please ???

On each end of the prop shafts under the car are Universal Joints - they connect the shafts to the diffs and transfer box....if they haven't been greased or maintained, they wear and fall apart or snap.

the VCU is the Viscous Coupling Unit - this little baby is what allows the front and rear axles to turn at different speeds during normal driving, but as soon as that speed differential gets bigger due to wheel slip, the VCU locks up to ensure maximum traction to both driven axles....the VCU has been known to lock up solid not allowing this speed differential between axles and during normal driving with corners etc, it can put undue stress on the axle diffs as one axle is trying to turn the other axle faster than it needs to and the diff gives out....

Usual check for VCU is to jack one wheel up with GB in Neutral and try turning it with a long bar on a wheel nut - should be stiff - locked solid = VCU duff, spin freely = Diff or UJs Duff

ok thanks mate appriciate it

whats the most likely suspect ?

also what sort of ££ am i looking at ???

is it safe to drive ? real urgent to fix etc ?

polsta said:

ok thanks mate appriciate it

whats the most likely suspect ?

also what sort of ££ am i looking at ???

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UJ is the most likely suspect caused a SV8 said by lack of maintenance and/or VCU seized. UJ a few quid if the prop is not damaged, VCU about £300 or so both if you DIY.

polsta said:

it started to get a bit louder/more of a rumble/vibrating, i was thinking this doesnt sound good..then clunk clang clunk break up sort of sound from underneath......

... drove it 35 odd miles nervously, but it was SMOOTH !! totaly smooth, no rumble although took it easy and nervously, but it felt nicer than it

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UJ given up the ghost, and whole prop shaft dropped off?

A long shot I guess and perhaps not even mechanically possible, but it would fit the symptoms!

Pete

if the prop shaft had fallen off it wouldnt drive would it ? but there was no debris anywhere i had a look

polsta said:

if the prop shaft had fallen off it wouldnt drive would it ? but there was no debris anywhere i had a look

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Yes it would still drive on the one remaining diff.

Datatek said:

UJ is the most likely suspect caused a SV8 said by lack of maintenance and/or VCU seized. UJ a few quid if the prop is not damaged, VCU about £300 or so both if you DIY.

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ok thanks, when it was last in a few weekls ago when i had the damper, drag link and track rod ass done,i said give everything a good look over

i cant diy this sort of thing i do not have alcue, how much labour time would you guess ?

if its just the uj how much would that likley cost ?

polsta said:

ok thanks, when it was last in a few weekls ago when i had the damper, drag link and track rod ass done,i said give everything a good look over

i cant diy this sort of thing i do not have alcue, how much labour time would you guess ?

if its just the uj how much would that likley cost ?

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Sorry, no idea on garage costs, can't afford to use them, I have to DIY

i cant diy this sort of thing

how much labour time would you guess ? ie how long to fix

polsta said:

i cant diy this sort of thing

how much labour time would you guess ? ie how long to fix

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Aslong as there is no damage to the UJ mating faces etc, no more than a couple of hours allowing for stuck bolts etc....

As attached...

ok thanks, after tomorrow im off work until weds so can get it to mates garage and leave it there a few days to get fixed

how safe/unsafe is it to drive ?

also, is there any visual check i can do now quick i can go have a good look underneath ..

Make sure both front and rear prop shafts are attached and sound.

If you are sure the noise came from the front - it would be prudent to remove the front prop shaft in the short term.....if it is a UJ on the front shaft, the last thing you want is for it to fail completly and the Shaft fall onto the floor as that can be very dangerous.

Many have removed a prop shaft and driven on 2wd only, but I would advise only for a short time as it could potentially knacker the VCU.

Ok thanks, i just gota get it home, just had a look it all looks ok althou didnt get under,il gjave a better look when i finish and can get trousers grubby, all i got to do is get it home after work really, altho i have breakdown cover, but i dont wammt damage,hoping my mate can sort it over the weekend ,bit gutted,thought it was all sorted for the winter,is it not as bad or worse than the diff going ?

Don't think it's a UJ... from what he's saying, the rumbling / grumbling from underneath has disappeared since the big 'bang'... I think if one of his props had come off 'in flight', he would've know about it....

My guess is a diff broken up internally... And now there's no drive though that diff, the noise has gone... And he's driving on one diff...

Thats what i guessed clarky,altho i have no expirience of any of this, but there hasnt been long term rumbling, just last few weeks, would the diff go that quick ? wasnt a loud bang noise, more a breaking clang clunking break mash up kind of sound, and very quiet n smooth,better than its been in ages, although i took it very easy nervously,but it felt like as if id had the rumbling fixed

What quick tests could be done at home tonight to maybe determine ?

Pete The Biker said:

UJ given up the ghost, and whole prop shaft dropped off?

A long shot I guess and perhaps not even mechanically possible, but it would fit the symptoms!

Pete

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Pete if one end dropped I think you would know , it be smashing the undercarriage up before the other end let go

defender300td1 said:

Pete if one end dropped I think you would know , it be smashing the undercarriage up before the other end let go

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...or the car would be pole-vaulting down the road!

Yeah - I agree with you. But at that point we weren't clear on the scale of the grindy-crashy-bang noise. At least it's an easy thing to check and rule out!

Pete